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Grumpy
Malmoesoldier

QUOTE
With Thermate it doesnt leave any physical clues behind.


Thermite/thermate makes a pretty good weapon if it is a tank or truck you wish to disable, it will bore a hole straight down through armor and engine blocks and is also good for sinking steel boats and starting massive fires(even in the pouring rain). I used it sometimes while in Vietnam.

But it will not cut a steel beam in a horizontal direction on it's own, it acts strictly in a vertical direction. That is why real demolition teams NEVER use it to bring down steel structures(except in lances to manually cut beams with a stream of oxygen or compressed air).

There is a patent for a heavy, bulky refractory trough which is meant to contain the reaction and direct it sideways, but no one to my knowledge has ever made one, and of the thousands that would be necessary to bring down a building, not one has been found. In fact not one explosively cut beam, shaped charge channel, det cord residue, timer, detonator, or any other physical clue(nor chemical) for the use of large amounts of explosives was found anywhere on the WTC complex. Before you start denigrating every fireman, policeman or recovery worker as being in on it(which is what it would take for such clues to be hiden) THINK!!!

Yes, even thermite/mate leaves behind clues, and the BATF and FBI and these other agencies are very good at finding those clues. If they didn't find any clue you can be pretty certain there is nothing to find.

Grumpy cool.gif
Malmoesoldier
wcelliott. 600 C under 45 min dont make the columns fail. NIST tests was under 700 C in almost 4 hours + they where under MAX loads. Read the report?

Thomas Eager, Professor of Materials Engineering at MIT: It is known that structural steel begins to soften around 425c and loses about half its strength at 650c … but even a 50% loss of strength is still insufficient, by itself, to explain the WTC collapse … Even with its strength halved, the steel could still support two to three times the stresses imposed by a 650c fire."


QUOTE
IT WAS A TEST, not actual conditions


Its was office material that burned the entire time in wtc not jet fuel. A office fire needs 6-8 hours if the temp is going to STAY at 1000 C. In 45 min it will go down to lower temperatures after it has reached its peak temp. The experts from arup.com AGREES with me!. Its not a secret. But you believe that 600 C in 45 min will make the columns to fail. So please read the nist report of the tests they did of WTC STEEL under 700 C in almost 4 hours.

QUOTE (->
QUOTE
IT WAS A TEST, not actual conditions


Its was office material that burned the entire time in wtc not jet fuel. A office fire needs 6-8 hours if the temp is going to STAY at 1000 C. In 45 min it will go down to lower temperatures after it has reached its peak temp. The experts from arup.com AGREES with me!. Its not a secret. But you believe that 600 C in 45 min will make the columns to fail. So please read the nist report of the tests they did of WTC STEEL under 700 C in almost 4 hours.

USGS says they saw ERODED steel


lol they have pictures of molten iron?.

QUOTE
Again, no steel could be unambiguously identified as having seen elivated temps in the original fires ONLY


Al-ciada sent all the steel to china and destroyed the evidence. They have no proof of core columns that reached higher temps then 250 C and they have no evidence of any support columns that reached any higher then 600 C. So the NIST report is a THEORY not evidence.

And one more thing it was NOT aluminum that came out from the tower, aluminum cant get that orange color it has a silvery color.
einsteen
If one thinks the cause of an event is C1 one starts of course looking for C1. If C1 is not found does that then mean that we have to sweep out the history of building collapses out of our mind and assume the improbable ? How far could one go then using this method? It is raining and the building collapses, one doesn't find C1 and we have no proof other than R1, then R1 caused the collapse ? I prefer to believe that an other method is used, even if we don't have the knowledge of the method or material, than to believe fire did it.

Isn't it a matter of statistics ? Of course if wtc7 falls the probability that it collapsed was 100%, that's aftermath. But strictly speaking that doesn't prove that it was P(fire)=100%, it could be P(unknown)=100%. If FEMA talks about a low probability of occurrence they literally mean P(fire)=very small, but also P(explosives)=0. Now you can assume P(rocketfuel)=50% or maybe even P(rocketfuel)=5%, but everything that is higher than P(fire) is a hypothesis, just like fire itself is a hypothesis.


I'm a P(unknown)>P(fire)'er and I'm proud of it wink.gif biggrin.gif tongue.gif
Grumpy
einsteen

QUOTE
If one thinks the cause of an event is C1 one starts of course looking for C1


That is going about it backwards.

1). event

2). examine evidence left by event

3). postulate causes based on the evidence you DO find

4). test postulates against known principles by testing

5). compare test results with evidence

6). adjust postulates, repeat step 4). and 5). until results agree with evidence

7). publish results for peer review

NIST's reports have been in peer review for 4 years, noone has challenged their conclusions.

Grumpy cool.gif
Bryn Richards
QUOTE (newton+May 30 2007, 03:29 PM)
cordite was smelled at the pentagon.

Noses are not accurate sensory equipment. I was talking about actual tests, with machines in a laboratory, to detect traces of explosive material.
Grumpy
Malmoesoldier

QUOTE
Thomas Eager, Professor of Materials Engineering at MIT: It is known that structural steel begins to soften around 425c and loses about half its strength at 650c … but even a 50% loss of strength is still insufficient, by itself, to explain the WTC collapse … Even with its strength halved, the steel could still support two to three times the stresses imposed by a 650c fire."


But at 1000C the steel loses 85% of it's strength and that is easily enough for it to fail, especially given the massive damage caused by the impacts.

QUOTE (->
QUOTE
Thomas Eager, Professor of Materials Engineering at MIT: It is known that structural steel begins to soften around 425c and loses about half its strength at 650c … but even a 50% loss of strength is still insufficient, by itself, to explain the WTC collapse … Even with its strength halved, the steel could still support two to three times the stresses imposed by a 650c fire."


But at 1000C the steel loses 85% of it's strength and that is easily enough for it to fail, especially given the massive damage caused by the impacts.

A office fire needs 6-8 hours if the temp is going to STAY at 1000 C.


Repitition does not make this lie true. Cite a source or drop this dogma.

QUOTE
The experts from arup.com AGREES with me!.


CITE A SOURCE.

Maybe about a normal office fire. The towers were not a normal office fire but a multi-floor, widespread instant ignition of the available fuel which reached and sustained temps above 1000C in just a few minutes. And when the steel reached a temp where it could no longer stand the load, it failed.

QUOTE (->
QUOTE
The experts from arup.com AGREES with me!.


CITE A SOURCE.

Maybe about a normal office fire. The towers were not a normal office fire but a multi-floor, widespread instant ignition of the available fuel which reached and sustained temps above 1000C in just a few minutes. And when the steel reached a temp where it could no longer stand the load, it failed.

lol they have pictures of molten iron?.


If they do, then you should be able to CITE A SOURCE!!!

QUOTE
So the NIST report is a THEORY not evidence.


The Theory of Gravity is also a theory, as is Relativity. But the evidence SUPPORTS those current theories, as the evidence supports NIST's theory. Until you come up with evidence that falsifies any of these theories any ideas you have otherwise are simply Hypotheses and for the hypothesis of explosives, there is no valid supporting evidence, just opinion and testimony(and the testimony is also unsupported by facts).

QUOTE (->
QUOTE
So the NIST report is a THEORY not evidence.


The Theory of Gravity is also a theory, as is Relativity. But the evidence SUPPORTS those current theories, as the evidence supports NIST's theory. Until you come up with evidence that falsifies any of these theories any ideas you have otherwise are simply Hypotheses and for the hypothesis of explosives, there is no valid supporting evidence, just opinion and testimony(and the testimony is also unsupported by facts).

And one more thing it was NOT aluminum that came out from the tower, aluminum cant get that orange color it has a silvery color.


Your uneducated OPINION is noted, others more versed in chemistry disagree, however. Unless one of your eyes is a spectrograph this is likely to just remain an opinion. I am educated enough to say "I don't know" but aluminum(with impurities) is the most likely canidate.

Grumpy cool.gif
frater plecticus
QUOTE (Bryn Richards+May 30 2007, 03:09 PM)
Did they ever find any traces of explosives in the WTC ruins? - I don't recall ever hearing about any.

No just a half-burnt terrorist passport and probably a couple of Korans and flight manuals too..
Malmoesoldier
QUOTE
But at 1000C the steel loses 85% of it's strength and that is easily enough for it to fail, especially given the massive damage caused by the impacts.


No 1000C under just some minutes will not make it fail. But you believe it was 1000C for 45 minutes witch is not true.

QUOTE (->
QUOTE
But at 1000C the steel loses 85% of it's strength and that is easily enough for it to fail, especially given the massive damage caused by the impacts.


No 1000C under just some minutes will not make it fail. But you believe it was 1000C for 45 minutes witch is not true.

CITE A SOURCE.


Replace all the * with http

I gave u that before. Arup.com agrees with me that a fire needs 6-8 hours for it to stay at 1000C. Source: *img169.imagevenue.com/view.php?image=09918_ARUPELD_122_459lo.JPG

QUOTE
if they do, then you should be able to CITE A SOURCE!!!


*pubs.usgs.gov/of/2005/1165/images/

*pubs.usgs.gov/of/2005/1165/images/IRON-04-IMAGE.TIF

QUOTE (->
QUOTE
if they do, then you should be able to CITE A SOURCE!!!


*pubs.usgs.gov/of/2005/1165/images/

*pubs.usgs.gov/of/2005/1165/images/IRON-04-IMAGE.TIF

I am educated enough to say "I don't know" but aluminum(with impurities) is the most likely canidate.


No i can say it as FACT. I have talked with *www.sapagroup.com and what did they say? "It doesn't glow, irrespective of temperature." And no, hot, partially burned, solid organic materials (e.g., furniture, carpets, partitions and computers) CANT display an orange glow like NIST says it can. Steven jones proves this in experiments. So it can only be thermite and there are smoke coming from it, a different smoke then the smoke from the towers, that smoke is what a thermite reaction looks like. And the corner where it comes out collapses minutes after it has appeared in the corner. You need a furnace to make aluminum glow but when it is flowing out from the furnace it has its silvery color. And the saucepan Steven jones had his aluminum in was made of steel and he heated it upp to 1000C. lol
NEU-FONZE
Frater Plecticus:

20,000 body parts.... no black boxes.....

But an intact "terrorist" passport?

Hmmmm....
einsteen
QUOTE (frater plecticus+May 30 2007, 05:35 PM)
No just a half-burnt terrorist passport and probably a couple of Korans and flight manuals too..

Yeah, also very unlikely, I cannot imagine that.

Are we in that single universe in the infinite collection of Everett's many-worlds universe in which all those improbable probabilities merge together ? biggrin.gif
David B. Benson
QUOTE (metamars+May 30 2007, 02:36 AM)
Now that you see what I meant by the "Disney criteria", what do you have to say about whether Greening, Benson, et. al., meet such criteria?

Thanks, I had somehow missed the name.

This criterion is far too simple-minded to deal properly with the problem of overfitting which occurs in systems of equations with many parameters and insufficient data to support the parameter settings.

This does not occur for either Greening-style or B & V style one-dimensional models. In the case of WTC 1 there are 15 data values, time-drop pairs, for the first three seconds of the collapse. For WTC 2 there are 8 data values for the first four seconds. Here are parameters:

(1) mass loss as a function of height. Set to zero for the first three seconds, based on observations.
(2) stretch. B & V use 0.18. I use 0.14 simply for the reason that this gives essentially the same value of E1 for both towers.
(3) E1

So finally, there is only the one parameter to be estimated. There is plenty of data to support the estimate. Looks solid to me.

(Around here, land use law was changed, the change justified by a much shakier application of atmospheric physics, microparticle distributions and an old lung clearance model.)
newton
QUOTE
Giuliani replied by saying, "I didn't realize the towers would collapse." He later added, "No one that I know of had any idea they would implode. That was a complete surprise."


so many lies. hard to keep track of, eh, rudy?

link to story
frater plecticus
QUOTE (einsteen+May 30 2007, 06:24 PM)
Yeah, also very unlikely, I cannot imagine that.

Are we in that single universe in the infinite collection of Everett's many-worlds universe in which all those improbable probabilities merge together ?  biggrin.gif

Yeah it's a bit like the Bin Laden "confession" tape (the ONE and ONLY copy) which was found in a safe house in Afghanistan...



The mind boggles.



Uncle Sam's lucky finds

Anne Karpf
Tuesday March 19, 2002

QUOTE
It started the day after the attacks on the twin towers, with the discovery of a flight manual in Arabic and a copy of the Koran in a car hired by Mohammed Atta and abandoned at Boston airport. In the immediate shocked aftermath of the attacks, these findings were somehow reassuring: American intelligence was on the case, the perpetrators were no longer faceless.

In less than a week came another find, two blocks away from the twin towers, in the shape of Atta's passport. We had all seen the blizzard of paper rain down from the towers, but the idea that Atta's passport had escaped from that inferno unsinged would have tested the credulity of the staunchest supporter of the FBI's crackdown on terrorism.

Yet we were still in the infancy of coincidence. On September 24 the belongings of alleged terrorist Zacarias Moussaoui threw up a cropdusting manual, while four days later came Atta's suicide note, the one with the counsel to shine your shoes before you meet your maker - a piece of advice which seemed suspiciously Norman Rockwellesque. It was here, too, that the stuff about 72 virgins awaiting him in heaven first started to circulate.

In December the laughing, boasting video of Osama bin Laden was unearthed in a house in Jalalabad. The new year saw no let-up in this serendipitous trove - January turned up an email sent by "shoe bomber" Richard Reid from a Paris cybercafe (and found on its hard disk) shortly before boarding the Paris-Miami flight in which he claimed responsibility in advance for downing the plane. (Luckily or carelessly, depending on your perspective, Reid had pocketed a business card from the cybercafe.)

And then, last Friday, Major General Frank Hagenbeck revealed that Americans had found a whole shelf of field manuals on undertaking terrorist activity, to put beside the instruction manual on how to use light automatic weapons left in a training camp in January.

Apart from the fact that the al-Qaida network seem to have a catastrophic way with lost property, isn't it strange that these most demonised and potent of terrorists seem unable to operate any weapons without a manual? Dad's Army is nothing - this bunch sounds as if they wouldn't be able to programme the video. And if the quality of their manuals is anything like those most of us have come across, they will still be wrestling with them long after the guarantee has run out.

Of course you could interpret these discoveries differently. You could detect in them the clear hand of American propaganda. This isn't, of course, to claim a dirty tricks department somewhere in the heart of Washington. That would have you immediately accused of peddling conspiracy theories, though I'm coming to think that conspiracy theories have had a bad press. What are they, after all, but "joined-up government" by another name?


http://www.guardian.co.uk/september11/stor...,669961,00.html

David B. Benson
QUOTE (forthetrees+May 30 2007, 03:51 AM)
Are we pointing out all typos now, or only being selective in doing so?

You always seem to use normal, unconfined air in arriving at acceleration values.

(1) I always use the spell checker. Clearly it does not notice all mistakes. I always use the exact wording in quotations, so am obligated to use [sic] for mistakes.

(2) For the first few seconds, the speed is slow enough that air resistance can be neglected. At the end of crush-down, the speed is about 50 m/s and the air resistance is enough to take into account in a careful analysis. This is actually important in obtaining a crush-down time of close to 13 seconds for WTC 1, this then ending up being in good agreement with the timing derived from the Heath video.
So all is well...
wcelliott
Funny you should mention improbabilities.

What would Occam say is more likely, a covert plan to drop three buildings in plain view of thousands of spectators using tons of odorless explosives smuggled past building security going off without a hitch, or 16 Arabs who hate our guts hijacking four airplanes?

There's a difference between cynicism and wisdom.
frater plecticus
QUOTE (wcelliott+May 30 2007, 08:35 PM)
Funny you should mention improbabilities.

What would Occam say is more likely, a covert plan to drop three buildings in plain view of thousands of spectators using tons of odorless explosives smuggled past building security going off without a hitch, or 16 Arabs who hate our guts hijacking four airplanes?

There's a difference between cynicism and wisdom.

You seemed to have reduced everything into an either/or statement.


Planes or explosives?



Did I mention explosives?



There is no difference between any one thing and any other. Uncle Al sums it up nicely...



QUOTE
AL I,4: "Every number is infinite; there is no difference."


Mathematical ideas involve what is called a continuum, which is, superficially at least, of a different character to the physical continuum. For instance, in the physical continuum, the eye can distinguish between the lengths of one-inch stick and a two-inch stick, but not between these which measure respectively one thousand miles and one thousand miles and on inch, though the difference in each case is equally an inch. The inch difference is either perceptible or not perceptible, according to the conditions. Similarly, the eye can distinguish either the one-inch or the two-inch stick from one of an inch and a half. But we cannot continue this process indefinitely -- we can always reach a point where the extremes are distinguishable from each other but their mean from neither of the extremes. Thus, in the physical continuum, if we have three terms, A, B, and C, A appears equal to B, and B to C, yet C appears greater than A. Our reason tells us that this conclusion is an absurdity, that we have been deceived by the grossness of our perceptions. It is useless for us to invent instruments which increase the accuracy of our observations, for though they enable us to distinguish between the three terms of our series, and to restore the theoretical Hierarchy, we can always continue the process of division until we arrive at another series: A', B', C', where A' and C' are distinguishable from each other, but where neither is distinguishable from B'.

On the above grounds, modern thinkers have endeavoured to create a distinction between the mathematical and the physical continuum, yet it should surely be obvious that the defect in our organs of sense, which is responsible for the difficulty, shows that our method of observation debars us from appreciating the true nature of things by this method of observation.
However, in the case of the mathematical continuum, its character is such that we can continue indefinitely the process of division between any two mathematical expressions so-ever, without interfering in any way with the regularity of the process, or creating a condition in which two terms become indistinguishable from each other. The mathematical continuum, moreover, is not merely a question of series of integral numbers, but of other types of numbers, which, like integers, express relations between existing ideas, yet are not measurable in terms of that series. Such numbers are themselves parts of a continuum of their own, which interpenetrates the series of integers without touching it, at least necessarily.

For example: the tangents of angles made by the separation of two lines from coincidence to perpendicularity, increases constantly from zero to infinity. But almost the only integral value is found at the angle of 45 degrees where it is unity.

It may be said that there is an infinite number of such series, each possessing the same property of infinite divisibility. The ninety tangents of angles differing by one degree between zero and ninety may be multiplied sixty fold by taking the minute instead of the degree as the co-efficient of the progression, and these again sixty fold by introducing the second to divide the minute. So on ad infinitum.

continues.....

A short digression is necessary. There may be some who are still unaware of the fact, but the mathematical and physical sciences are in no sense concerned with absolute truth, but only with the relations between observed phenomena and the observer. The statement that the acceleration of falling bodies is thirty-two feet per second, is only the roughest of approximation at the best. In the first place, it applies to earth. As most people know, in the Moon the rate is only one-sixth as great. But, even on earth, it differs in a marked manner between the poles and the equator, and not only so, but it is affected by so small a matter as the neighborhood of a mountain.
It is similarly inaccurate to speak of "repeating" an experiment. The exact conditions never recur. One cannot boil water twice over. The water is not the same, and the observer is not the same. When a man says that he is sitting still, he forgets that he is whirling through space with vertiginous rapidity.

It is possibly such considerations that led earlier thinkers to admit that there was no expectation of finding truth in anything but mathematics, and they rashly supposed that the apparent ineluctability of her laws constitutes a guarantee of their coherence with truth. But mathematics is entirely a matter of convention, no less so than the rules of Chess or Baccarat. When we say that "two straight lines cannot enclose a space", we mean no more than we are unable to think of them as doing so. The truth of the statement depends, consequently, on that of the hypothesis that our minds bear witness to truth. Yet the insane man may be unable to think that he is not the victim of mysterious persecution. We find that no reason for believing him. It is useless to reply that mathematical truths receive universal consent, because they do not. It is a matter of elaborate and tedious training to persuade even the few people when we teach of the truth of the simplest theorems in Geometry. There are very few people living who are convinced -- or even aware -- of the more recondite results of analysis. It is no reply to this criticism to say that all men can be convinced if they are sufficiently trained, for who is to guarantee that such training does not warp the mind?

But when we have brushed away these preliminary objections, we find that the nature of the statement itself is not, and cannot be, more than a statement of correspondences between our ideas. In the example chosen, we have five ideas; those of duality, of straightness, of a line, of enclosing, and of space. None of these are more than ideas. Each one is meaningless until it is defined as corresponding in a certain manner to certain other ideas. We cannot define any word soever, except by identifying it with two or more equally undefined words. To define it by a single word would evidently constitute a tautology.
We are thus forced to the conclusion that all investigation may be stigmatized as obscurum per obscurium. Logically, our position is even worse. We define A as BC, where B is DE, and C is FG. Not only does the process increase the number of our unknown quantities in Geometrical progression at every step, but we must ultimately arrive at a point where the definition of Z involves the term A. Not only is all argument confined within a vicious circle, but so is the definition of the terms on which any argument must be based.

It might be supposed that the above chain of reasoning made all conclusions impossible. But this is only true when we investigate the ultimate validity of our propositions. We can rely on water boiling at 100 degrees Centigrade,<<In revising this comment, I note with amusement that it had escaped me that 100 degrees C. is by definition the temperature at which water boils! I have seen it boil at about 84 degrees C. on the Baltoro Glacier, and determined my height above sea-level by observing the boiling point so often that I had quite forgotten the original conditions of Celsius.>> although, for mathematical accuracy, water never boils twice running at precisely the same temperature, and although, logically, the term water is an incomprehensible mystery.
To return to our so-called axiom; Two straight lines cannot enclose a space. It has been one of the most important discoveries of modern mathematics, that this statement, even if we assume the definition of the various terms employed, is strictly relative, not absolute; and that common sense is impotent to confirm it as in the case of the boiling water. For Bolyai, Lobatschewsky, and Riemann have shown conclusively that a consistent system of geometry can be erected on any arbitrary axiom soever. If one chooses to assume that the sum of the interior angles of a triangle is either greater than or less than two right angles, instead of equal to them, we can construct two new systems of Geometry, each perfectly consistent with itself, and we possess no means soever of deciding which of the three represents truth.

I may illustrate this point by a simple analogy. We are accustomed to assert that we go from France to China, a form of expression which assumes that those countries are stationary, while we are mobile. But the fact might be equally well expressed by saying that France left us and China came to us. In either case there is no implication of absolute motion, for the course of the earth through space is not taken into account. We implicitly refer to a standard of repose which, in point of fact, we know not to exist. When I say that the chair in which I am sitting has remained stationary for the last hour, I mean only "stationary in respect to myself and my house". In reality, the earth's rotation has carried it over one thousand miles, and the earth's course some seventy thousand miles, from its previous position. All that we can expect of any statement is that it should be coherent with regard to a series of assumption which we know perfectly well to be false and arbitrary.

It is commonly imagined, by those who have not examined the nature of the evidence, that our experience furnishes a criterion by which we may determine which of the possible symbolic representations of Nature is the true one. They suppose that Euclidian Geometry is in conformity with Nature because the actual measurements of the interior angles of a triangle tell us that their sum is in fact equal to two right angles, just as Euclid tells us that theoretical considerations declare to be the case. They forget that the instruments which we use for our measurements are themselves conceived of as in conformity with the principles of Euclidian Geometry. In other words, them measure ten yards with a piece of wood about which they really known nothing but that its length is one-tenth of the ten yards in question.

The fallacy should be obvious. The most ordinary reflection should make it clear that our results depend upon all sorts of condition. If we inquire, "What is the length of the thread of quicksilver in a thermometer?", we can only reply that it depends on the temperature of the instrument. In fact, we judge temperature by the difference of the coefficients of expansion due to heat of the two substances, glass and mercury.

Again, the divisions of the scale of the thermometer depend upon the temperature of boiling water, which is not a fixed thing. It depends on the pressure of the earth's atmosphere, which varies (according to time and place) to the extent of over twenty per cent. Most people who talk of "scientific accuracy" are quite ignorant of elementary facts of this kind.

It will be said, however, that having defined a yard as the length of a certain bar deposited in the Mint in London, under given conditions of temperature and pressure, we are at least in a position to measure the length of other objects by comparison, directly or indirectly, with that standard. In a rough and ready way, that is more or less the case. But if it should occur that the length of things in general were halved or doubled, we could not possibly be aware of the other so-called laws of Nature. We have no means so-ever of determining even so simple a matter as to whether one of two events happens before or after the other.

Let us take an instance. It is well known that the light of the sun requires some eight minutes to reach the earth. Simultaneous <<Simultaneity, closely considered, possesses no meaning soever. See A.A.Eddington, "Space, Time and Gravitation", 61.>> {WEH NOTE: SIC. This is page 51 in Eddington, op. cit. 1920 edition, 1959 reprint: "The denial of absolute simultaneity is a natural complement to the denial of absolute motion ..."} phenomena in the two bodies would therefore appear to be separated in time to that extent; and, from a mathematical standpoint, the same discrepancy theoretically exists, even if we suppose the two bodies in question to be only a few yards one more remote than the other. Recent consideration of these facts has show the impossibility of determining the fact of priority, so that it may be just as reasonable to assert that a dagger-thrust is caused by a wound as vice versa. Lewis Carroll has an amusing parable to this effect in "Through the Looking-Glass", which work, by the way, with its predecessor, is packed with examples of philosophical paradox. <<If I strike a billiard ball, and it moves, both my will and its motion have causes long antecedent to the act. I may consider both my Work and its reaction as twin effects of the eternal Universe. The moved arm and ball are part of a state of the Cosmos which resulted necessarily from its momentarily previous state, and so, back for ever. Thus, my Magical Work is only on of the cause-effects necessarily concomitant with the cause-effects which set the ball in motion. I may therefore regard the act of striking as a cause-effect of my original Will to move the ball, though necessarily previous to its motion. But the case of Magical work is not quite analogous. For I am such that I am compelled to perform Magick in order to make my Will to prevail; so that the cause of my doing the Work is also he cause of the ball's motion, and there is no reason why one should precede the other, See Book 4, Part III, for a full discussion. (Since writing the above, I have been introduced to "Space, Time and Gravitation", where similar arguments are adduced.)>>

We may now return to our text "Every number is infinite". The fact that every number is a term in a mathematical continuum is no more an adequate definition than if we were to describe a picture as Number So-and-So in the catalogue. Every number is a thing in itself,<<I regret to find myself in disagreement with the Hon. Bertrand Russell with regard to the conception of the nature of Number.>> possessing an infinite number of properties peculiar to itself.

Let us consider, for a moment, the numbers 8 and 9. 8 is the number of cubes measuring one inch each way in a cube which measures two inches each way; while 9 is the number of squares measuring one inch each way in a square measuring three inches each way. There is a sort of reciprocal correspondence between them in this respect.

By adding one to eight, we obtain nine, so that we might define unity as that which has the property of transforming a three-dimensional expansion of two into a two-dimensional expansion of three. But if we add unity to nine, unity appears as that which has the power of transforming the two-dimensional expansion of three aforesaid into a mere oblong measuring 5 by 2. Unity thus appears as in possession of two totally different properties. Are we then to conclude that it is not the same unity? How are we to describe unity, how know it? Only by experiment can we discover the nature of its action on any given number. In certain minor respects, this action exhibits regularity. We know, for example, that it uniformly transforms an odd number into an even one, and vice versa, but that is practically the limit of what we can predict as to its action.

We can go further, and state that any number soever possesses this infinite variety of powers to transform any other number, even by the primitive process of addition. We observe also how the manipulation of any two numbers can be arranged so that the result is incommensurable with either, or even so that ideas are created of a character totally incompatible with our original conception of numbers as a series of positive integers. We obtain unreal and irrational expressions, ideas of a wholly different order, by a very simple juxtaposition of such apparently comprehensible and commonplace entities as integers.

There is only one conclusion to be drawn from these various considerations. It is that the nature of every number is a thing peculiar to itself, a thing inscrutable and infinite, a thing inexpressible, even if we could understand it.

In other words, a number is a soul, in the proper sense of the term, an unique and necessary element in the totality of existence.

We may not turn to the second phrase of the text: "there is no difference". It must strike the student immediately that this is, on the face of it, a point blank contradiction of all that has been said above. What have we done but insist upon the essential difference between any tow numbers, and show that even their sequential relation is little more than arbitrary, being indeed rather a convenient way of regarding them for the purpose of coordinating them with out understanding than anything else? On a similar principle, we number public vehicles or telephones without implication even of necessary sequence. The appellation denotes nothing beyond membership of a certain class of objects, and is indeed expressly chosen to avoid being entangled in considerations of any characteristics of the individual so designated except that cursory designation.
when it is said that there is no difference between numbers (for in this sense I think we must understand the phrase), we must examine the meaning of the word 'difference'. Difference is the denial of identity in the first place, but the word is not properly applied to discriminate between objects which have no similarity. One does not ask, "What is the difference between a yard and a minute?" in practical life. We do ask the difference between two things of the same kind. The Book of the Law is trying to emphasize the doctrine that each number is unique and absolute. Its relations with other numbers are therefore in the nature of illusion. They are the forms of presentation under which we perceive their semblances; and it is to the last degree important to realize that these semblances only indicate the nature of the realities behind them in the same way in which the degrees on a thermoetric scale indicate heat. It is quite unphilosophical to say that 50 degrees Centigrade is hotter than 40 degrees. Degrees of temperature are simply conventions invented by ourselves to describe physical states of a totally different order; and, while the heat of a body may be regarded as an inherent property of its own, our measure of that heat in no way concerns it.

We use instruments of science to inform us of the nature of the various objects which we wish to study; but our observations never reveal the thing as it is in itself. They only enable us to compare unfamiliar with familiar experiences. The use of an instrument necessarily implies the imposition of alien conventions. To take the simplest example: when we say that we see a thing, we only mean that our consciousness is modified by its existence according to a particular arrangement of lenses and other optical instruments, which exist in our eyes and not in the object perceived. So also, the fact that the sum of 2 and 1 is three, affords us but a single statement of relations symptomatic of the presentation to us of those numbers.

We have, therefore, no means soever of determining the difference between any two numbers, except in respect of a particular and very limited relation. Furthermore, in view of the infinity of every number, it seems not unlikely that the apparent differences observed by us would tend to disappear with the disappearance of the arbitrary conditions which we attach to them to facilitate, as we think, our examination. We may also observe that each number, being absolute, is the centre of its universe, so that all other numbers, so far as they are related to it, are its appanages. Each number is, therefore, the totality of the universe, and there cannot be any difference between one infinite universe and another. The triangle ABC may look very different from the standpoints of A, B, and C respectively; each view is true, absolutely; yet it is the same triangle.

The above interpretation of the text is of a revolutionary character, from the point of view of science and mathematics. Investigation of the lines here laid down will lead to the solution of these grave problems which have so long baffled the greatest minds of the world, on account of the initial error of attaching them on lines which involve self-contradiction. The attempt to discover the nature of things by a study of the relations between them is precisely parallel with the ambition to obtain a finite value of Pi. Nobody wishes to deny the practical value of the limited investigations which have so long preoccupied the human mind. But it is only quite recently that even the best thinkers have begun to recognize that their work was only significant within a certain order. It will soon be admitted on all hands that the study of the nature of things in themselves is a work for which the human reason is incompetent; for the nature of reason is such that it must always formulate itself in proportions which merely assert a positive or negative relation between a subject and a predicate. Men will thus be led to the development of a faculty, superior to reason, whose apprehension is independent of the hieroglyphic representations of which reason so vainly makes use.
wcelliott
You call that "summing it up nicely"?

Incidentally, if that's the same Uncle Al I know, you shouldn't take anything he writes too literally, he sometimes likes to spoof pseudo-intellectuals by writing nonsense and hoping they'll quote him.

(He and I used to belong to ISPE and correspond on occasion.)
NEU-FONZE
wcelliott:

"A covert plan to drop three buildings in plain view of thousands of spectators using tons of odorless explosives smuggled past building security going off without a hitch...."

Ammonium perchlorate-spiked sprayed on thermal insulation would do nicely!

(Mixed with HMX and a polysulfide binder)

Not exactly odorless, I know, but the HCl fumes would be indistinguishable from the PVC degradation fumes....
frater plecticus
QUOTE (wcelliott+May 30 2007, 08:55 PM)
You call that "summing it up nicely"?

Incidentally, if that's the same Uncle Al I know, you shouldn't take anything he writes too literally, he sometimes likes to spoof pseudo-intellectuals by writing nonsense and hoping they'll quote him.

(He and I used to belong to ISPE and correspond on occasion.)

Possible but Doubtful .. he died 60 years ago.

Edward Alexander Crowley, (12 October 1875 – 1 December 1947; the surname is pronounced /'krəʊ.li/ i.e. with the first syllable sounding like "crow" in English) was a British occultist, writer and mystic.[1]


There you go again..calling me a psuedo-intellectual.


Here I am (or not) in my state of perpetual samadhi


The master of my own destiny or the author of my own downfall?
adoucette
QUOTE (Malmoesoldier+May 30 2007, 01:15 PM)

Replace all the * with http

I gave u that before. Arup.com agrees with me that a fire needs 6-8 hours for it to stay at 1000C. Source: *img169.imagevenue.com/view.php?image=09918_ARUPELD_122_459lo.JPG

frater plecticus
QUOTE (adoucette+May 30 2007, 10:43 PM)
http://img169.imagevenue.com/view.php?imag...D_122_459lo.JPG

user posted image

????

Arthur

It's a metaphor, Arthur.....

laugh.gif
newton
architects and engineers for 911 truth
NEU-FONZE
That photo.......For a physics site this is pretty low and a serious breach of protocol. What's next?
frater plecticus
QUOTE (NEU-FONZE+May 30 2007, 11:04 PM)
That photo.......For a physics site this is pretty low and a serious breach of protocol. What's next?

Hanging, drawing and quartering sounds good to me.
NEU-FONZE
My last comment was not intended to be critical of this site. PHYSORG is a pretty good site when you compare it to the competition. After posting on another "educational" site (I wont mention), how could I say otherwise?
NEU-FONZE
DBB:

Have you seen the paper on the mechanics of collapse I mentioned? It shows field measurements of a CD involving an upper block falling (eventually) at constant velocity, not acceleration.
David B. Benson
QUOTE (David B. Benson+May 30 2007, 07:31 PM)
Thanks, I had somehow missed the name.

This criterion is far too simple-minded to deal properly with the problem of overfitting which occurs in systems of equations with many parameters and insufficient data to support the parameter settings.

This does not occur for either Greening-style or B & V style one-dimensional models. In the case of WTC 1 there are 15 data values, time-drop pairs, for the first three seconds of the collapse. For WTC 2 there are 8 data values for the first four seconds. Here are parameters:

(1) mass loss as a function of height. Set to zero for the first three seconds, based on observations.
(2) stretch. B & V use 0.18. I use 0.14 simply for the reason that this gives essentially the same value of E1 for both towers.
(3) E1

So finally, there is only the one parameter to be estimated. There is plenty of data to support the estimate. Looks solid to me.

(Around here, land use law was changed, the change justified by a much shakier application of atmospheric physics, microparticle distributions and an old lung clearance model.)

I forgot to add:

(4) mass at each elevation. For the first few seconds, it suffices to treat this as a constant which is determinable from NCSTAR1-6D.

===========================

And do note that the B & V crush-down equation is just Newton's Laws applied for the appropriate boundary conditions as set forth in the four simplifying assumptions.

Similar assumptions are used in science and engineering to form constitutive laws, or equations if you prefer, in every situation where the actual micro or meso scale phenomena are too difficult to treat from first principles. The crush-down equation is the constitutive law for total progressive collapse.

I repeat my offer to defend the four simplifying assumptions. I'll not do so de novo, since B & V have already done so in their paper. But if objections are raised, I'll certainly respond...
David B. Benson
QUOTE (NEU-FONZE+May 30 2007, 11:40 PM)
It shows field measurements of a CD involving an upper block falling (eventually) at constant velocity, not acceleration.

No, not yet.

From the constant speed, I'll guess that the demolitiioners used exact the right amount of explosives...
NEU-FONZE
Yes, the resisting force offered by the lower section is NOT like the force from a giant spring.
David B. Benson
NCSTAR1-2, page 33 (147 ordinal)

"Outside the core, the primary trusses acted compositely with the 4 in. concrete slab and the 1 1/2 in. metal deck. In the model, the average depth of the slab plus deck was modeled as 4.35 in."

I don't quite know how to interpret this, but it does sound as though the metal deck was considerably more than 22 guage sheet steel...
wcelliott
QUOTE
Uncle Al sums it up nicely...


Wrong Uncle Al.

http://www.mazepath.com/uncleal/

Read some of his stuff and you'll understand how I got confused.

I wasn't aiming the "pseudo-intellectual" bit at you directly, only that they're a favorite target of his, and I was cautioning you to avoid the traps he lays.

OTOH, now that you mention it...

Grumpy
Malmoesoldier

QUOTE
*img169.imagevenue.com/view.php?image=09918_ARUPELD_122_459lo.JPG


As much as I like Buffy, as far as I know she knows nothing about fires.

QUOTE (->
QUOTE
*img169.imagevenue.com/view.php?image=09918_ARUPELD_122_459lo.JPG


As much as I like Buffy, as far as I know she knows nothing about fires.

*pubs.usgs.gov/of/2005/1165/images/IRON-04-IMAGE.TIF


Tiny little pea shaped ball, just like your brain.

QUOTE
No i can say it as FACT.


No, you can't, nor can a failed cold fusion professor, who suddenly needed another line of work. It's not really a big change, as cold fusion turned out to be another pseudo-scientific con job too.

QUOTE (->
QUOTE
No i can say it as FACT.


No, you can't, nor can a failed cold fusion professor, who suddenly needed another line of work. It's not really a big change, as cold fusion turned out to be another pseudo-scientific con job too.

And the saucepan Steven jones had his aluminum in was made of steel and he heated it upp to 1000C. lol


Then this professor of pseudo-science is lucky to be alive. If for any reason a thermite reaction had taken place he would at least lost his arm.

QUOTE
Steven jones proves this in experiments


Professor Jones is just a failed physicist(cold fusion is a bust) who needed another line of work and was willing to sacrifice any scientific credibility he might have had. He has been shown in error so often we just assume everything he says is wrong, that way we are right more often than not. I have never given a dime to him and his fellow hucksters, have you??? Baseball cap, T-shirt, CD or book??? SUCKER!!!!

Grumpy cool.gif
wcelliott
QUOTE
Edward Alexander Crowley, (12 October 1875 – 1 December 1947; the surname is pronounced /'krəʊ.li/ i.e. with the first syllable sounding like "crow" in English) was a British occultist, writer and mystic.[1]


You needn't bother describing how to pronounce his name, I never intend to quote him.

One of the vast number of disparate concepts he alludes to is Determinism, which is based on a false premise. I therefore feel it safe to discount the rest of the thesis as likewise false.
Pierre-Normand
QUOTE (David B. Benson+May 31 2007, 12:19 AM)
NCSTAR1-2, page 33 (147 ordinal)

"Outside the core, the primary trusses acted compositely with the 4 in. concrete slab and the 1 1/2 in. metal deck. In the model, the average depth of the slab plus deck was modeled as 4.35 in."

I don't quite know how to interpret this, but it does sound as though the metal deck was considerably more than 22 guage sheet steel...

That's the thickness of the corrugated steel deck. It's still 22 gauge but the corrugations are 3/2 inch deep. See figure 1.8, NCSTAR1-2A p.8 (pdf 42)
Alan (ex elevator man)
QUOTE (Malmoesoldier+May 30 2007, 07:45 AM)
And thats because they SHIPPED all the other steel to CHINA and DESTROYED THE EVIDENCE. You can believe in a theory if you want, i like proof of something before i will believe in it.

Honestly, you really need to quit posting this crapola you find on the 'troother' sites. Here's proof of just one of your statements being wrong.

Photo Release - WTC Steel used to make bow of U.S. Navy ship.
Capracus
QUOTE (NEU-FONZE+May 30 2007, 11:22 PM)
My last comment was not intended to be critical of this site. PHYSORG is a pretty good site when you compare it to the competition. After posting on another "educational" site (I wont mention), how could I say otherwise?

Circle jerk. The other site.
wcelliott
QUOTE
you really need to quit posting this crapola you find on the 'troother' sites


That's all they have, crapola, innuendo, polemics, rhetoric, and paranoid delusions. The physics has already been explained ad nauseum, no facts supporting the CD/CT case exist. The only "mysteries" are associated with physics they don't get and lies deliberately spread for political purposes.

This is supported only by their ardent desire for it to be true. They already hate Bush, so they're trying to "backfill" the rationale for that hatred.
frater plecticus
QUOTE (wcelliott+May 31 2007, 12:53 AM)

You needn't bother describing how to pronounce his name, I never intend to quote him.

One of the vast number of disparate concepts he alludes to is Determinism, which is based on a false premise. I therefore feel it safe to discount the rest of the thesis as likewise false.

Self-determination was more Crowley's thing.

Disregarding an entire thesis on the premise of partial non belief in the thesis as a whole??


Thanks for the Uncle Al links..
wcelliott
QUOTE
Disregarding an entire thesis on the premise of partial non belief in the thesis as a whole??


How wrong does something have to be before you don't believe it?

Funny that self-determination should be his thing, what with him asserting the Determinists' argument denying Free Will.

(blah, blah, blah, ... billiard balls..., blah, blah, blah...)
einsteen
A constant velocity E1-model ??? That can only if the collapsing mass is constant (no mass is added for example) and the values E1,m_f,g,h are exactly balanced. In other words if an E1 model falls it falls fast..

Judy Wood also got a constant speed model with elastic collisions..., didn't she ?
Pierre-Normand
QUOTE (einsteen+May 31 2007, 09:46 AM)
A constant velocity E1-model ??? That can only if the collapsing mass is constant (no mass is added for example) and the values E1,m_f,g,h are exactly balanced. In other words if an E1 model falls it falls fast..

Judy Wood also got a constant speed model with elastic collisions..., didn't she ?

This is a CD model, so it is a crush-up process. The mass must be diminishing linearly as a function of time. But if E1 isn't a constant either, then why couldn't it be such that gravity is exactly compensated by the diminishing resistance of each successive floor being crushed? You are right that this indicates a fine balance.

Judy Wood's model involves neither elastic collisions nor inelastic ones. She stacks billard balls at each floor level, and when the topmost ball reach the next one, it turns to dust while it sets the second one free to accelerate at g *from rest* (while the dust moves up or sideways). This process gets iterated for every floor. The collisions are neither elastic nor inelastic since zero momentum gets transferred to the balls being hit, and since she assumes zero resistance from the structure. So this is a momentum-destruction model.
frater plecticus
QUOTE (wcelliott+May 31 2007, 09:09 AM)

How wrong does something have to be before you don't believe it?

Funny that self-determination should be his thing, what with him asserting the Determinists' argument denying Free Will.

(blah, blah, blah, ... billiard balls..., blah, blah, blah...)

I suggest you read a little more Crowley before wrongfully accusing him of having a deterministic philosophy.


True Will is a term found within the mystical system of Thelema—established in 1904 with Aleister Crowley's writing of The Book of the Law—and is defined at times as a person's grand destiny in life and at other times as a moment to moment path of action that operates in perfect harmony with Nature. This Will does not spring from conscious intent, but from the interplay between the deepest Self and the entire Universe. Therefore, the enlightened Thelemite is one who is able to eliminate or bypass one's ego-created desires, conflicts, and habits, and tap directly into the Self/Universe nexus. Theoretically, at this point, the Thelemite acts in alignment with Nature, just as a stream flows downhill, with neither resistance nor "lust of result."


Quotations from Aleister Crowley

* "The most common cause of failure in life is ignorance of one's own True Will, or of the means by which to fulfill that Will." (from Magick, Book 4, p. 127)
* "A man who is doing his True Will has the inertia of the Universe to assist him." (from Magick, Book 4, p.128)
* "One cannot do one's True Will intelligently unless one knows what it is." (from Magick, Book 4, p.174)
* "Know firmly, O my Son, that the True Will connot err; for it is thine appointed Course in Heaven, in whose Order is Perfection." (from Liber Aleph, p. 13)
* "True Will should spring, a fountain of Light, from within, and flow unchecked, seething with Love, into the Ocean of Life." (from Little Essays Towards Truth, p.76)


As with your friend "uncle Al"..it has to be taken with a pinch of salt.....most of it is allegorical or metaphorical...
einsteen
Deterministic philosophy, LOL. For years I was always really into that kind of stuff... Some people hate a deterministic world picture, some love it. But it doesn't really matter. If the laws of physics determine our behaviour it doesn't matter whether they are deterministic or not. And free will... it's how you look at it, if the universe is superdeterministic you could say that you have no free will, but if the universe isn't you also have no free will, then your will is random. Then the decisions you made are a kind of fuzzy logic of course still determined by the fixed laws of nature. Personally I believe in fixed laws of nature, because we have good reasons to believe that there are universal laws, the question whether they will be known (or are knowable) one day is something different, we are monkey’s of course. An other way to look at free will (and that is what I use now, because otherwise you can make yourself mad) is: You are the one that controls the universe, you have a free will, your free will implies determinism. It doesn't matter if the 'real' world is deterministic or not and the answer can never be given I think. And this is the last line I write about it in this thread.
metamars
QUOTE (David B. Benson+May 30 2007, 07:31 PM)
Thanks, I had somehow missed the name.

This criterion is far too simple-minded to deal properly with the problem of overfitting which occurs in systems of equations with many parameters and insufficient data to support the parameter settings.

This does not occur for either Greening-style or B & V style one-dimensional models. In the case of WTC 1 there are 15 data values, time-drop pairs, for the first three seconds of the collapse. For WTC 2 there are 8 data values for the first four seconds. Here are parameters:

(1) mass loss as a function of height. Set to zero for the first three seconds, based on observations.
(2) stretch. B & V use 0.18. I use 0.14 simply for the reason that this gives essentially the same value of E1 for both towers.
(3) E1

So finally, there is only the one parameter to be estimated. There is plenty of data to support the estimate. Looks solid to me.

Googling for information on overfitting, I saw links for contexts of statistics and neural networks. I'm not sure we're talking about the same thing.

In the case of statistics, it seems that overfittings refers to curve-fitting with polynomials, such that the curve passes through more of the pionts, but variance of distance from curve points (in general) to data points nevertheless increases.

Assuming you consider mass loss and stretch reasonable, and assuming the rest of BV to be reasonable, I can see the logic of claiming that W(u) (similar to Greening's E1) can be verified by looking at collapse time predicted.

However, are their models reasonable?

Other than as suggestive first approximations, no. It's an article of faith to presume that, in spite of works such as that of Calladine and English, taking Wp as an upper bound, the way BZ did, is valid. Not science, but faith. And this is in spite of the fact that there was already an emphasis, in the field of engineering (and with at least one peer-reviewed journal), devoted to impacts.

So, BZ, BV, Greening, et. al., have shown that if you ignore CD evidence to the contrary, and ignore relevant analyses from the domain of impact engineering, and ignore corrections necessitated by 'cross connections' (perimeter spandrels and core beams, e.g.), then a gravity driven collapse is plausible.

I find that interesting, and of value, but it's hardly the end of the story.

I'm sure Bazant, Verdure, Greening, et. al., will welcome realistic FEA models which might show that that they were close, indeed, or way off.

Correct?
metamars
QUOTE (einsteen+May 31 2007, 02:47 PM)
we are monkey’s of course.

I am not a monkey, even if I do like bananas. smile.gif
wcelliott
QUOTE
if the universe is superdeterministic you could say that you have no free will


When Newton's laws were published, some philosophers said exactly that. His laws are exact, which leaves no room for conscious entities to make decisions on their own. Fortunately, quantum physics is inexact, so there is at least the possibility for Free Will in this universe. Whether we exercise it or not is our choice. That, in itself, is a decision we couldn't make if the universe were indeed "superdeterministic".
frater plecticus
QUOTE (wcelliott+May 31 2007, 04:16 PM)

When Newton's laws were published, some philosophers said exactly that. His laws are exact, which leaves no room for conscious entities to make decisions on their own. Fortunately, quantum physics is inexact, so there is at least the possibility for Free Will in this universe. Whether we exercise it or not is our choice. That, in itself, is a decision we couldn't make if the universe were indeed "superdeterministic".

newton assumes a clockwork universe
newton
QUOTE (metamars+May 31 2007, 04:10 PM)
So, BZ, BV, Greening, et. al., have shown that if you ignore CD evidence to the contrary, and ignore relevant analyses from the domain of impact engineering, and ignore corrections necessitated by 'cross connections' (perimeter spandrels and core beams, e.g.), then a gravity driven collapse is plausible.



ya, true, true. the more forces and force vectors you can ignore, the better for the official lie.

for example, regarding squibs(i think the new meaning of 'squib' can be added to the english language, now, ....they added 'DOH!', recently), there was not enough overpressure. when the building is down to the fiftieth floor, there is only 2 atmospheres of pressure. even if NONE of the air escaped out the sides and top.

in order to have a 'syringe effect' that would create a path for air to compress to greater than 2 atmospheres halfway through the collapse, a funnel would be needed to squeeze air that is spread out horizontally, into an increasingly smaller diameter vertical tube. HVAC systems, elevator shafts, etc, are not upward facing funnels.

i didn't hear any celebrating over the launching of architects and engineers for truth. i wouldn't hold my breath waiting for celebration over an FEA collapse model. (which, if we can all remember, was already done in china, and provided 1:30 second collapse times for a natural collapse)
adoucette
QUOTE (metamars+May 31 2007, 11:10 AM)
However, are their models reasonable?

Other than as suggestive first approximations, no. It's an article of faith to presume that, in spite of works such as that of Calladine and English, taking Wp as an upper bound, the way BZ did, is valid. Not science, but faith. And this is in spite of the fact that there was already an emphasis, in the field of engineering (and with at least one peer-reviewed journal), devoted to impacts.


I am quite tired of your continual reference to Calladine and English as if somehow their work was relevant to this topic, but with NO EVIDENCE to back that up.

So I went looking.

Whooops.

See http://www-mech.eng.cam.ac.uk/profiles/vsd/papers/ijie.pdf

The micro-inertia of the individual cell walls can a!ect the deformation of cellular structures as discussed by Klintworth [9] and more recently by Reid and co-workers [10-13]. Under dynamic loading the collapse mode may switch from the quasi-static mode to a new mode involving additional stretching which dissipates more energy. Thus, an observed rate-sensitive response can have an inertial origin. Calladine and English [14] examined this phenomenon for two classes of
structures, Type I and II, as sketched in Fig. 1. Type I structures have a `flat topped" quasi-static stress versus strain curve: under dynamic loading micro-inertia plays little role and the quasi-static bending mode of collapse is maintained.

The Calladine and English reference is the one Metamars has been using: Calladine CR, English RW. Strain-rate and inertia e!ects in the collapse of two types of energy absorbing structures. Int J Mech Sci 1984;26(11/12):689.

So NOW we have the diagrams that Metamars CLAIMED were similar to Bazant's.

User posted image

http://i117.photobucket.com/albums/o72/ard...estructures.jpg

QUOTE (Metamars+ Jan 15th)
The shape of BZ's Figure 5(d) is essentially that of Calladine and English's (CE, hereafter) Figure 1(a) - type II. This should not surprise anybody, since the geometries are "approximately" the same. ("approximately" is in quotes because, while CE's type 2 and BZ's plastically buckling column are slender, and hence very different from CE's type 1, this doesn't mean that there may not be some significant differences between them, as implied by their differing (apparently) conclusions)

I will hereafter speak of CE as having contradicted BZ, but note that I haven't confirmed that, yet.


Well what do you know, they are NOT.

laugh.gif

Arthur
newton
http://www.youtube.com/watch?v=Wn-MCCZ3O1M

here is something that pope grumpy has decreed 'impossible' because he used thermite in vietnam fourty years ago.

3bodyproblem
Hello,

I am currently working on my own model for the collapse mechanism. I have posted much of this already in the JREF forum in response to Gregory Urich's questions about Bazant's analysis. I have no wish to tackle the question of collapse initiation. It is my contention that the exterior walls did little else than retain the falling mass within the footprint, providing little or no support. I beleive this is supported by close inspection of the videos. Close up footage shows the floor trusses pulling away from the exterior East and North walls well ahead of the falling upper section. YouTube videos:

watch?v=rABYbvpz4yY

8:51-8:53, 9:09-9:10, 9:29-9:30 and at 9:58

Notice also that the NE corner remains relatively untouched until the upper section collides with it.

I also would note that a substantial portion of the core remained free standing and did not contribute to the KE of the collapse mechanism.

watch?v=rABYbvpz4yY

At 7:35 in the above video you can see the core standing almost even with the 75th mechanical floor of the North Tower. And:

watch?v=ACbFf...elated&search=

note 1:36 2:28 and 3:12 of the above video

(for the most part it appears the core was behind the collapse wave in both towers). This means the upper crumbling mass and impacted floors were the only available KE. In my personal model of the collapse, the only significant figure is the energy required to separate the floor trusses from the core and exterior columns which would remain essentially constant for the duration of the collapse. Hence the steady progression of the collapse noted by many. As the crumbling mass built up within the footprint the horizontal forces on the exterior columns "peeled" them away from the core and outside the footprint. The ability of the exterior columns to retain mass inside the footprint would be proportional to their thickness and rigidity not to mention inertial mass. Thus, most of the upper crumbling section, most of the floors, a small potion of the core and a small portion of the exterior remained in the footprint during the collapse.

I apologize if this has already been discussed, but I have yet to find any calculations incorporated in this theory. Any help, links to past threads or observations on this would be much appreciated. Thanks.
Alan (ex elevator man)
QUOTE (newton+May 31 2007, 11:13 AM)
http://www.youtube.com/watch?v=Wn-MCCZ3O1M

here is something that pope grumpy has decreed 'impossible' because he used thermite in vietnam fourty years ago.

Ha ha. Yeah Newt, that contraption was what, ten times the size of the 'column'? So you're saying they snuck in 40 of those things ten times bigger than the column it was attached to, and nobody noticed it. Oh wait, then they had to cross-connect them with a timer as well. That's rich.
metamars
QUOTE (adoucette+May 31 2007, 04:35 PM)
I am quite tired of your continual reference to Calladine and English as if somehow their work was relevant to this topic, but with NO EVIDENCE to back that up.

So I went looking.

Whooops.

See http://www-mech.eng.cam.ac.uk/profiles/vsd/papers/ijie.pdf

The micro-inertia of the individual cell walls can a!ect the deformation of cellular structures as discussed by Klintworth [9] and more recently by Reid and co-workers [10-13]. Under dynamic loading the collapse mode may switch from the quasi-static mode to a new mode involving additional stretching which dissipates more energy. Thus, an observed rate-sensitive response can have an inertial origin. Calladine and English [14] examined this phenomenon for two classes of
structures, Type I and II, as sketched in Fig. 1. Type I structures have a `flat topped" quasi-static stress versus strain curve: under dynamic loading micro-inertia plays little role and the quasi-static bending mode of collapse is maintained.

The Calladine and English reference is the one Metamars has been using: Calladine CR, English RW. Strain-rate and inertia e!ects in the collapse of two types of energy absorbing structures. Int J Mech Sci 1984;26(11/12):689.

So NOW we have the diagrams that Metamars CLAIMED were similar to Bazant's.

User posted image

http://i117.photobucket.com/albums/o72/ard...estructures.jpg



Well what do you know, they are NOT.

laugh.gif

Arthur

If you look at Bazant and Verdure's "Crushing Force vs. Floor displacement" (their Figure 3), and then compare to Calladine and English's Type II Force vs. displacement curve in the Figure 1 you link to, you can clearly see the similarity.

Apparently, you have confused the Type II appartus diagram with Bazant/Verdure Force vs. Displacement graph, even though the nearly identical CE Type II Force vs. Displacement graph was right next to it.

Have you?

Either that, or you are trying to make a big deal out of the fact that CE Type II apparatus looks like 2 slender columns, from the side, while BZ's buckling is diagramatically illustrated as occuring along a single column line.

Either way, your complaints have no merit.

I think it was chainsaw who suggested that the width of the CE plates made them behave quite differently from so many rods just sitting next to each other. I don't believe such corrections would amount to much, and he never supported his opinion with any quantitative analysis.

More seriously, the complaint has been made that rods or plates will behave differently than I-beams or box beams. I posted a bunch of references which would might have shed light on this, but nobody has looked into this.

Hopefully, somebody at ae911truth.org, with more skills than I have, will do this for us.

Fearless truth-seeker that you are, I'm sure that you will welcome the input of qualified individuals who can look into this for the more relevant cases of box and I-columns.

Right?
metamars
QUOTE (Grumpy+May 31 2007, 12:48 AM)

Professor Jones is just a failed physicist(cold fusion is a bust) who needed another line of work and was willing to sacrifice any scientific credibility he might have had. He has been shown in error so often we just assume everything he says is wrong, that way we are right more often than not. I have never given a dime to him and his fellow hucksters, have you??? Baseball cap, T-shirt, CD or book??? SUCKER!!!!

Grumpy cool.gif

As noted previously about another of your posts, your very premise is a lie. You want us to believe that "Professor Jones is just a failed physicist" because "cold fusion is a bust".

Professor Jones clearly distinguished between muon catalyzed fusion and between a-neutronic cold fusion, ala Pons and Fleishman. He explained this in his recent paper in the journal of 911 studies http://journalof911studies.com/volume/2007...11SciMethod.pdf


Furthermore, your timing for this tired bit of "debunking" baloney is not very good:
From http://www.infinite-energy.com/iemagazine/...ereignited.html
QUOTE

In my IE #72 editorial, “March Madness and March Meeting Madness,” I suggested that history would be made on March 5, 2007. It was. The setting was the 2007 March Meeting of the American Physical Society (APS) in Denver, Colorado, during the largest gathering of physicists in the world. Although the actual session appeared to be low-key, later I found out it wasn’t; truly great excitement occurred because during two consecutive sessions (Cold Fusion I and Cold Fusion II), held in Room 401 of the Colorado Convention Center, there were four talks that show the two big bugaboos no longer exist that have supposedly kept physicists from believing in Condensed Matter Nuclear Science (CMNS): 1) Not being able to reproduce the excess heat effect on demand (which is now possible), and 2) The lack of high energy particles and radiation (both phenomena can be created, now, on demand).


While in Grumpy-world, "cold fusion is a bust", in the real world, physicists continue to work on this, and have managed to make the phenomenon readily reproducible. How much more wrong could you be?

Well, don't let inconvenient facts get in the way of your slanderous talking points, Grumpy. If you did, you would have to change your name, and we couldn't have that, now could we?

adoucette
I like it, metamars attempt to substantiate cold fusion quotes from a magazine whose issue is devoted to Pyramid Power.

user posted image

PRICELESS

laugh.gif

Arthur
metamars
QUOTE (metamars+May 31 2007, 06:17 PM)


Professor Jones clearly distinguished between muon catalyzed fusion and between a-neutronic cold fusion, ala Pons and Fleishman.

I should add that Fleischmann also attended. It may be the case that Pons and Fleishman discovered a real effect, but their explanation was totally off.


The presentation titles and abstracts are available at:

http://meetings.aps.org/Meeting/MAR07/Sess...onEventID=64258
http://meetings.aps.org/Meeting/MAR07/Sess...onEventID=57225
adoucette
QUOTE (metamars+May 31 2007, 12:48 PM)
If you look at Bazant and Verdure's "Crushing Force vs. Floor displacement" (their Figure 3), and then compare to Calladine and English's Type II Force vs. displacement curve in the Figure 1 you link to, you can clearly see the similarity.

Apparently, you have confused the Type II appartus diagram with Bazant/Verdure Force vs. Displacement graph, even though the nearly identical CE Type II Force vs. Displacement graph was right next to it.

Have you?

Either that, or you are trying to make a big deal out of the fact that CE Type II apparatus looks like 2 slender columns, from the side, while BZ's buckling is diagramatically illustrated as occuring along a single column line.

Either way, your complaints have no merit.

I think it was chainsaw who suggested that the width of the CE plates made them behave quite differently from so many rods just sitting next to each other. I don't believe such corrections would amount to much, and he never supported his opinion with any quantitative analysis.

More seriously, the complaint has been made that rods or plates will behave differently than I-beams or box beams. I posted a bunch of references which would might have shed light on this, but nobody has looked into this.

Hopefully, somebody at ae911truth.org, with more skills than I have, will do this for us.

Fearless truth-seeker that you are, I'm sure that you will welcome the input of qualified individuals who can look into this for the more relevant cases of box and I-columns.

Right?

What is CLEAR is you were attempting to MISLEAD.

Why?

That diagram in NO WAY represents what the columns in the towers were like.

That diagram does not appear to relate to either B&Z or B&V.

To claim that your view is true because others "never supported his opinion with any quantitative analysis" or "I posted a bunch of references which would might have shed light on this, but nobody has looked into this" is utter BS.

Finally, to claim that they are related because the SIMPLISTIC Force vs Displacement diagram is SIMILAR is truly HILARIOUS.

The POINT is, all future references by YOU to Calladine & English will be IGNORED until you can show HOW AND WHY they should be considered relevant to the issue under discussion.

Arthur
metamars
QUOTE (adoucette+May 31 2007, 06:31 PM)
I like it, metamars attempt to substantiate cold fusion quotes from a magazine whose issue is devoted to Pyramid Power.

user posted image

PRICELESS

laugh.gif

Arthur


Cold fusion has been actively sidelined and even ridiculed (even as research was continuing in governement labs), so it shouldn't surprise anybody that no regular, scientific journals of cold fusion exist. However, that may change sooner rather than later:

QUOTE

As I said, although superficially the session appeared to be low-key, many in the audience of about 80 physicists were shocked. During a “Meet the Editors” reception the following day, I learned that a number of editors of Physical Review went to our two sessions and paid attention to what was presented. This fact became obvious in a conversation I had with Jack Sandweiss (a high energy, experimental physicist from Yale University), editor of one of the most prestigious APS journals, Physical Review Letters. Our discussion even became so specific and intense that I found myself debating with him about what might and might not be possible, theoretically, in novel forms of nuclear reactions.

Also, I sensed intense interest by other physicists when I went to re-introduce myself to the new editor-in-chief of all of the Physical Review journals, Dr. Gene Sprouse. (I actually met Dr. Sprouse when he was a professor and I was a graduate student 30 years ago at the State University of New York at Stony Brook.) By chance, before I said anything, he stared at my name badge and with an intense look in his eyes, he said, “I have heard a lot about you during this meeting.”

An important point is that information about CMNS has not appeared in mainstream physics journals because the editors of these journals, as well as most physicists, have not known whether the effects are real. This has created a Catch-22 situation in which, since information about CMNS has not appeared in the Physical Review (PR) journals, most of the potential reviewers of CMNS papers would reject them on the basis that these kinds of papers have little credibility since they have not appeared in PR publications. As a consequence, the fact that the editors of PR paid close attention to the two sessions indicates that significant progress is being made in ending the effective embargo of CMNS articles in PR journals. Several weeks later, Richard Van Noorden, a reporter from the Royal Society chemistry magazine, Chemistry World, contacted me about our session. In his article about cold fusion, which appeared on March 23, Richard Van Noorden wrote, “Chubb feels that Physical Review Letters, one of the top physics journals, may finally start accepting papers in the field.” The complete version of his article is available through the following link:

http://www.rsc.org/chemistryworld/News/200...ch/22030701.asp





The above link to Chemistry World gives us:
QUOTE (->
QUOTE

As I said, although superficially the session appeared to be low-key, many in the audience of about 80 physicists were shocked. During a “Meet the Editors” reception the following day, I learned that a number of editors of Physical Review went to our two sessions and paid attention to what was presented. This fact became obvious in a conversation I had with Jack Sandweiss (a high energy, experimental physicist from Yale University), editor of one of the most prestigious APS journals, Physical Review Letters. Our discussion even became so specific and intense that I found myself debating with him about what might and might not be possible, theoretically, in novel forms of nuclear reactions.

Also, I sensed intense interest by other physicists when I went to re-introduce myself to the new editor-in-chief of all of the Physical Review journals, Dr. Gene Sprouse. (I actually met Dr. Sprouse when he was a professor and I was a graduate student 30 years ago at the State University of New York at Stony Brook.) By chance, before I said anything, he stared at my name badge and with an intense look in his eyes, he said, “I have heard a lot about you during this meeting.”

An important point is that information about CMNS has not appeared in mainstream physics journals because the editors of these journals, as well as most physicists, have not known whether the effects are real. This has created a Catch-22 situation in which, since information about CMNS has not appeared in the Physical Review (PR) journals, most of the potential reviewers of CMNS papers would reject them on the basis that these kinds of papers have little credibility since they have not appeared in PR publications. As a consequence, the fact that the editors of PR paid close attention to the two sessions indicates that significant progress is being made in ending the effective embargo of CMNS articles in PR journals. Several weeks later, Richard Van Noorden, a reporter from the Royal Society chemistry magazine, Chemistry World, contacted me about our session. In his article about cold fusion, which appeared on March 23, Richard Van Noorden wrote, “Chubb feels that Physical Review Letters, one of the top physics journals, may finally start accepting papers in the field.” The complete version of his article is available through the following link:

http://www.rsc.org/chemistryworld/News/200...ch/22030701.asp





The above link to Chemistry World gives us:

Cold fusion back on the menu

22 March 2007


Most chemists would rather forget all about cold fusion. After the barrage of criticism dismissing Stanley Pons and Martin Fleischmann's sensational 1989 claims that nuclei could be forced to fuse and release excess energy at room temperature, only a small core of researchers has kept the idea from fading away entirely.

Yet preparations are under way for an invited symposium focusing on cold fusion and low-energy nuclear reactions at the American chemical society's (ACS) 2007 conference in Chicago next week. Isolated presentations have been scattered around ACS meetings before, and the American physical society (APS) groups together a number of cold fusion researchers every year, but the last comparable session was 'so far off I can't remember', according to cold fusion advocate George Miley, of the University of Illinois, US. Even Fleischmann himself has a paper at the ACS, though the eighty-year old chemist will not be attending. 



A low energy nuclear reaction cell used this year at the University of California, Berkeley, US, in an attempt to replicate research conducted at the US Space and Naval Warfare Systems Center, San Diego


© Steven B. Krivit 
'I feel there is a strong rebirth of interest in cold fusion,' said Miley. He and other cold fusion supporters are taking their ACS presence as one more indication of the subject's growing respectability. Organiser Jan Marwan said he was very surprised at how easy it was to gain acceptance for the symposium. But Gopal Coimbatore, program chair of the ACS's division of environmental chemistry, felt that unless a forum was provided, the subject might never get discussed; and 'with the world facing an energy crisis, it is worth exploring all possibilities'.

The chances of cold fusion meeting that crisis may seem remote, but enthusiasts point to recent research from the US navy's Space and naval warfare systems center (Spawar) in San Diego, California. Here, Stanislaw Szpak and Pamela Mosier-Boss have claimed a ream of evidence for nuclear reactions occurring in a system similar to the 1989 reports.

Pons and Fleischmann suggested that electrolysis could pack deuterium nuclei into a palladium lattice so tightly that they were fusing together; Szpak and Boss now claim to have speeded up this process by co-depositing palladium and deuterium onto a thin wire subjected to an electric field. They have used plastic
films - so-called CR-39 detectors - to track charged particles emerging from their reactions, publishing most recently in Naturwissenschaften. And, unlike the original 1989 experiments, the researchers claim their results are easily reproducible, with other groups reportedly detecting products of nuclear reactions such as alpha particles and gamma rays. 

Acceptance by the scientific community is still the main target for cold fusion advocates - hence the importance of replication, appearing at major conferences, and publishing in peer reviewed journals. In this at least, success seems imminent: Miley says his cold fusion paper is the first to be accepted to the Journal of Fusion Energy, which normally covers 'hot' thermonuclear fusion or sonofusion (which uses pulses of sound to rapidly compress bubbles in liquids). Meanwhile, Scott Chubb, who chaired a cold fusion session at an APS meeting in March, feels that Physical Review Letters, one of the top physics journals, may finally start accepting papers in the field. Avowed critics of cold fusion don't see anything to shout about, though. Frank Close, of the University of Oxford, UK, says he sees no renewed interest, 'just the usual suspects recycling'. Indeed, Fleischmann's ACS report is a re-presentation of research from the 1990s, showing that his calorimetry measurements were accurate. Bob Park, at the University of Maryland, US, agrees, but concedes that 'there are some curious reports - not cold fusion, but people may be seeing some unexpected low-energy nuclear reactions'.

But will the flare-up of cold fusion excitement last? Chubb is sure of it, but Fleischmann himself is less bullish. He approves of the Spawar research, but, as he told Chemistry World, 'my optimism is tempered by realism'. And Close's opinion is clear: 'Let's not confuse noise with signal'. 

Richard Van Noorden



This article is a preview from Chemistry World's April 2007 edition

adoucette
That's just circular logic.

In the first Chubb is claiming:

QUOTE
I learned that a number of editors of Physical Review went to our two sessions and paid attention to what was presented. This fact became obvious in a conversation I had with Jack Sandweiss (a high energy, experimental physicist from Yale University), editor of one of the most prestigious APS journals, Physical Review Letters. Our discussion even became so specific and intense that I found myself debating with him about what might and might not be possible, theoretically, in novel forms of nuclear reactions.


There is of course NO indication that the editors of PR agreed with ANYTHING Chubb had to say or to what was presented at the meetings.

Nor is there any actual support from Physical Review to Chubb's SELF ASSESSMENT when interviewed by someone from Chemistry World:

QUOTE (->
QUOTE
I learned that a number of editors of Physical Review went to our two sessions and paid attention to what was presented. This fact became obvious in a conversation I had with Jack Sandweiss (a high energy, experimental physicist from Yale University), editor of one of the most prestigious APS journals, Physical Review Letters. Our discussion even became so specific and intense that I found myself debating with him about what might and might not be possible, theoretically, in novel forms of nuclear reactions.


There is of course NO indication that the editors of PR agreed with ANYTHING Chubb had to say or to what was presented at the meetings.

Nor is there any actual support from Physical Review to Chubb's SELF ASSESSMENT when interviewed by someone from Chemistry World:

Meanwhile, Scott Chubb, who chaired a cold fusion session at an APS meeting in March, feels that Physical Review Letters, one of the top physics journals, may finally start accepting papers in the field.


When people IN the field were questioned it was somewhat less enthusiastic:

Fleischmann himself is less bullish ... as he told Chemistry World, 'my optimism is tempered by realism'.

Frank Close, of the University of Oxford, UK, says he sees no renewed interest, 'just the usual suspects recycling'. And Close's opinion is clear: 'Let's not confuse noise with signal'.

Arthur



NEU-FONZE
3bodyproblem:

Why do you claim that only "a small portion of the core .... remained in the footprint during the collapse."
metamars
QUOTE (adoucette+May 31 2007, 06:40 PM)
What is CLEAR is you were attempting to MISLEAD.

Why?

That diagram in NO WAY represents what the columns in the towers were like.

That diagram does not appear to relate to either B&Z or B&V.

To claim that your view is true because others "never supported his opinion with any quantitative analysis" or "I posted a bunch of references which would might have shed light on this, but nobody has looked into this" is utter BS.

Finally, to claim that they are related because the SIMPLISTIC Force vs Displacement diagram is SIMILAR is truly HILARIOUS.

The POINT is, all future references by YOU to Calladine & English will be IGNORED until you can show HOW AND WHY they should be considered relevant to the issue under discussion.

Arthur

Sorry, but misleading is your department. The force vs. displacement graphs are obviously similar. Anybody who doubts this can look at them.

To imply, as you do, that two examples of metal with similar geometries and similar force vs. displacement diagrams must have unrelated behavior due to impacts is disingenuous.

What is on display here (besides your penchant for distortion), of course, is your hypocrisy. Obviously, the CE Type II apparatus is not EXACTLY like WTC columns. However, the differences are a lot smaller than fantasies about "crush down, followed by crush up", e.g. Yet, you seem incapable of noticing the latter, just as you seem completely oblivious to the fact that integrating a Force vs. Displacement will give you energy dissipation in the case that the displacement is quasi-static.


You are welcome to "IGNORE" future references, by me, to Calladine and English. I sure do hope, though, that the heavyweights at ae911truth.org will take up the challenge to nail this down. It may turn out that box columns and I-columns are even more resistant to collapse (wrt dynamic effects) than a CE Type II apparatus (which, in fact, I am guessing is the case).

I suspect you may also expect this, as you seem awfully incurious about correcting OCT models for dynamic effects.
wcelliott
QUOTE
newton assumes a clockwork universe


Newton himself offered no explanations as to why his equations worked, only that they seemed an accurate description of how things worked.

He did, however, assume an Objective Reality, an assumption that breaks down in the quantum realm.
wcelliott
QUOTE
'Let's not confuse noise with signal'.


And more to the point, let's not confuse Cold Fusion with 9/11.

Even if Cold Fusion becomes validated, that doesn't mean that the WTC towers were felled with a CD.

Physics credentials don't convey an understanding of engineering principles.

The punchline of my favorite physics joke is "First, we assume a spherical chicken". Physicists are often best at problems where chickens can be assumed spherical.
metamars
QUOTE (adoucette+May 31 2007, 07:09 PM)
That's just circular logic.

In the first Chubb is claiming:



There is of course NO indication that the editors of PR agreed with ANYTHING Chubb had to say or to what was presented at the meetings.

Nor is there any actual support from Physical Review to Chubb's SELF ASSESSMENT when interviewed by someone from Chemistry World:



When people IN the field were questioned it was somewhat less enthusiastic:

Fleischmann himself is less bullish ... as he told Chemistry World, 'my optimism is tempered by realism'.

Frank Close, of the University of Oxford, UK, says he sees no renewed interest, 'just the usual suspects recycling'. And Close's opinion is clear: 'Let's not confuse noise with signal'. 

Arthur

Apparently, you missed the following:

QUOTE

In this at least, success seems imminent: Miley says his cold fusion paper is the first to be accepted to the Journal of Fusion Energy, which normally covers 'hot' thermonuclear fusion or sonofusion (which uses pulses of sound to rapidly compress bubbles in liquids).


You are free to accept or reject Chubb's impressions. However, the fact that they even attended speaks volumes. And no, they didn't say "The fact that we editors attended speaks volumes!!."

Finally, I didn't say that the sidelining would end soon rather than later. I said,

QUOTE (->
QUOTE

In this at least, success seems imminent: Miley says his cold fusion paper is the first to be accepted to the Journal of Fusion Energy, which normally covers 'hot' thermonuclear fusion or sonofusion (which uses pulses of sound to rapidly compress bubbles in liquids).


You are free to accept or reject Chubb's impressions. However, the fact that they even attended speaks volumes. And no, they didn't say "The fact that we editors attended speaks volumes!!."

Finally, I didn't say that the sidelining would end soon rather than later. I said,


However, that may change sooner rather than later:


metamars
QUOTE (wcelliott+May 31 2007, 07:31 PM)

And more to the point, let's not confuse Cold Fusion with 9/11.

Even if Cold Fusion becomes validated, that doesn't mean that the WTC towers were felled with a CD.

Physics credentials don't convey an understanding of engineering principles.

The punchline of my favorite physics joke is "First, we assume a spherical chicken". Physicists are often best at problems where chickens can be assumed spherical.

Ha! A cousin of mine is a mathematics professor, and years ago worked on a problem assuming spherical people in studies of radiation on them. If Americans' obesity problems continue to deteriorate, this may become quite realistic, unfortunately. sad.gif
3bodyproblem
QUOTE (NEU-FONZE+May, 07:10 PM)
3bodyproblem:

Why do you claim that only "a small portion of the core .... remained in the footprint during the collapse."


Please forgive me if it read that way i wrote it rather hurriedly. A small portion of the core remained in the footprint AND contributed to the collapse. You can clearly see a large section of the core (it appears to be at the 75th mechanical floor?) remains free standing after the collapse wave passes. This represents a tremendous amount of mass not part of the global collapse. I have estimated that perhaps as much as 80% of the core steel did not contribute.

adoucette
QUOTE (metamars+May 31 2007, 02:24 PM)
You are welcome to "IGNORE" future references, by me, to Calladine and English.

As I said references by YOU to Calladine & English will be IGNORED until you can show HOW AND WHY they should be considered relevant to the issue under discussion.

Such as:

QUOTE
It's an article of faith to presume that, in spite of works such as that of Calladine and English, taking Wp as an upper bound, the way BZ did, is valid.


So what is the actual BASIS of your claim "in spite of works..."

Arthur



David B. Benson
QUOTE (3bodyproblem+May 31 2007, 08:07 PM)
You can clearly see a large section of the core (it appears to be at the 75th mechanical floor?) remains free standing after the collapse wave passes.

I believe you are considering WTC 2. My understanding is that NIST estimates this as 40 stories, but nothing is said regarding whether it is the entire core or only a portion of it. I personally estimate that it is at least four column lines, i.e., half or more of the width.
3bodyproblem
QUOTE (David B. Benson+May 31 2007, 08:27 PM)
I believe you are considering WTC 2. My understanding is that NIST estimates this as 40 stories, but nothing is said regarding whether it is the entire core or only a portion of it. I personally estimate that it is at least four column lines, i.e., half or more of the width.

Yes, on WTC 2 the core remains standing in the video. I have estimated it to be the 75th floor, based on its relation to the mechanical floor on WTC1. And you are correct, from the angle you cannot tell exactly what portion of the core remains intact. I have assumed that a larger portion of the core remained standing the closer to the base of the tower.
David B. Benson
QUOTE (metamars+May 31 2007, 04:10 PM)
Googling for information on overfitting, ... I'm not sure we're talking about the same thing.

Assuming you consider mass loss and stretch reasonable, and assuming the rest of BV to be reasonable, I can see the logic of claiming that W(u) (similar to Greening's E1) can be verified by looking at collapse time predicted.

However, are their models reasonable?

Other than as suggestive first approximations, no.

So, BZ, BV, Greening, et. al., have shown that if you ignore CD evidence to the contrary, and ignore relevant analyses from the domain of impact engineering, and ignore corrections necessitated by 'cross connections' (perimeter spandrels and core beams, e.g.), then a gravity driven collapse is plausible.

I'm sure Bazant, Verdure, Greening, et. al., will welcome realistic FEA models which might show that that they were close, indeed, or way off.

(1) The same thing. Use your example of a simple mass-spring system. If I only know the period, I only know mc, not the mass m nor the compliance c.

(2) Mass loss for the first few seconds was negligible, by observation. Stretch is about the right size. The crush-down equation is correctly derived and the four simplifying assumptions are reasonable. (You have yet to argue otherwise.)

(3) Is Hook's Law reasonable? It is a phenomenological constitutive equation, not derived from first principles. The crush-down equation is a constitutive equation derived from first principles.

(4) Hook's Law is a first approximation and is used all the time. It is more than just suggestive and I claim the same holds for the crush-down equation.

(5) (a) No CD evidence at all. (cool.gif Impact studies are irrelevant to collapse progression. As I posted about earlier, they are also irrelevant to collapse initiation. © No corrections are necessary. The crush-down equation matches the data very well.

(6) You can obtain a modern FEA-style computer program from Applied Science Inc. Their advertising claims it can handle progressive collapse. Go to it. But the Greening and B & V analyses fit the data so these cannot be way off.

(7) Got it now? dry.gif
3bodyproblem
Based on NIST's analysis, which i tend to agree with, the first and most likely point to fail was the truss connection to the exterior columns. Most likely the combination of vertical force on the exterior and then shearing of the bolts on the truss plates. This would "funnel" the debris and keep it within the footprint. The next likely failure is the truss connection at the core, which would produce a "herring bone" effect, as the floors disconnected from the exterior and swung towards the core. As they swung down, they would have failed and fallen down, contributing to the collapse. I believe this is correct based on the video evidence.
David B. Benson
QUOTE (3bodyproblem+May 31 2007, 08:49 PM)
Yes, on WTC 2 the core remains standing in the video. I have estimated it to be the 75th floor, based on its relation to the mechanical floor on WTC1. And you are correct, from the angle you cannot tell exactly what portion of the core remains intact. I have assumed that a larger portion of the core remained standing the closer to the base of the tower.

Floors 41--42 were also mechanical floors in both towers.

After this portion finally collapsed, the remaining segment of the core, about 12 stories above grade at the maximum, appears from aerial photographs to be entirely intact from about floor 7 down.
David B. Benson
QUOTE (3bodyproblem+May 31 2007, 05:20 PM)
It is my contention that the exterior walls did little else than retain the falling mass within the footprint, providing little or no support. I beleive[sic] this is supported by close inspection of the videos. Close up footage shows the floor trusses pulling away from the exterior East and North walls well ahead of the falling upper section.
Notice also that the NE corner remains relatively untouched until the upper section collides with it.

(for the most part it appears the core was behind the collapse wave in both towers).

Yes. Poster shagster and I agree, base on data in NCSTAR1-6, around Table 4--2, that at most 20 MJ sufficed to disconnect the trusses from all seats, exterior and interior.

I can't watch the videos, so could you say more about 'close up footage', etc.?

What makes you think that the core was behind the collapse wave in both towers?

Of course, many aspects of the collapses have been done in great detail on this thread and the two earlier incarnations of it. Otherwise, you probably want a copy of Greening's "Energy Transfer" paper, available from the 911Myths sire, and the Bazant & Verdure paper, available from Professor Bazant's web pages.

You have an interestingly different slant on the collapses. Keep posting! smile.gif
3bodyproblem
QUOTE (David B. Benson+May 31 2007, 09:04 PM)
Floors 41--42 were also mechanical floors in both towers.

After this portion finally collapsed, the remaining segment of the core, about 12 stories above grade at the maximum, appears from aerial photographs to be entirely intact from about floor 7 down.

Yes, but floors 41-42 are aren't even visible in the video over the top of building in the foreground. You can clearly see the top of the core standing at 7:35 well behind the collapse wave. Any mass behind the collapse wave would not contribute to the KE. This is why much of the core steel is not a factor.
3bodyproblem
In addition, it is almost impossible for the exterior steel to contribute to the collapse KE as the forces, as are evident in the video evidence were outwards from the core. It could be argued that a small portion fell inwards, being pulled by say the trusses (just the odd one that managed to survive) or just the randomness of the falling debris itself. However, this would represent a very small amount. Again, the mushroom cloud that is often referred to clearly shows this. There would be a critical mass that remained in the footprint dictated by the ability of the exterior to withstand the horizontal forces created by the falling debris. This would be in direct proportion to the plate thickness. Thus the only constant would be the truss connections to the exterior and core. It is my understanding that these did not vary, as the floors were identical in construction (except at the 66th floor core dimension change) for the entire height of the building. I feel all of this concurs with the evidence we now have of the collapse.
David B. Benson
QUOTE (3bodyproblem+May 31 2007, 09:33 PM)
Thus the only constant would be the truss connections to the exterior and core. It is my understanding that these did not vary, as the floors were identical in construction (except at the 66th floor core dimension change) for the entire height of the building.

The truss connections were, indeed, constant on all trussed floors. There were, however, both partially and totally beamed floors. See the appendix to NCSTAR1-2A for the details.

No dimension change to the core from the first sub-basement to the PH Roof.
3bodyproblem
And yes I am aware of Mr. Greening's work and it was on his recommendation I posted this here, although indirectly. I have found very little wrong with the physics (Mr. Greening made a slight error and calculated the dimensions of the core columns at 65mm in width instead of 67mm in his derivation of impact energy to collapse 1 floor) It is my intent to show however, that the "energy to collapse 1 floor" was over estimated. More focus should be placed on the truss connections than the core or exterior columns ability to hold weight after collapse initiation. I believe a significant amount of the core was destroyed by gravity alone, as it was not built to be a freestanding structure. The structural integrity of the WTC relied on secure truss connections to maintain the weight on the exterior walls. Once the geometry was disturbed there was significantly less resistance to the global collapse. Thank you for hearing me.
3bodyproblem
QUOTE (David B. Benson+May 31 2007, 09:45 PM)
The truss connections were, indeed, constant on all trussed floors. There were, however, both partially and totally beamed floors. See the appendix to NCSTAR1-2A for the details.

No dimension change to the core from the first sub-basement to the PH Roof.

Thank you, I will take a look at NCSTAR1-2A for what you have mentioned.


There is a discrepancy with what you are saying and the blue prints. The blue prints indicate the core dimensions were reduced at floor 66 or 86. The core column construction also was changed from the w14 to rolled weld H i believe on floor 98. I will check and make sure of this later tonight. In either case I beleive this will not really change my figures, as only slightly more mass would be added to the PE. Have a great night.
adoucette
QUOTE (3bodyproblem+May 31 2007, 05:02 PM)
Thank you, I will take a look at NCSTAR1-2A for what you have mentioned.


There is a discrepancy with what you are saying and the blue prints. The blue prints indicate the core dimensions were reduced at floor 66 or 86. The core column construction also was changed from the w14 to rolled weld H i believe on floor 98. I will check and make sure of this later tonight. In either case I beleive this will not really change my figures, as only slightly more mass would be added to the PE. Have a great night.

The core column dimensions changed as they went up but AFAIK not the overall core dimensions.

See NIST NCSTAR 1-5G appendix B.

Arthur
David B. Benson
QUOTE (3bodyproblem+May 31 2007, 09:56 PM)
It is my intent to show however, that the "energy to collapse 1 floor" was over estimated. More focus should be placed on the truss connections than the core or exterior columns ability to hold weight after collapse initiation.

Using the data posted on earlier incarnations of this thread by NEU-FONZE, I used the Bazant & Verdure crush-down equation to find that value of E1 which best fits the data. I used the correct mass for the upper portion of both towers as given in NCSTAR1-6D.

E1 = 510 MJ

which is less than Greening's estimate, which was about 600--800 MJ, if I remember correctly.

But note that less than 4% of that energy was consumed in destroying the truss seats. You'll have to look at other means to use up the remaining energy.
Grumpy
metamars

QUOTE
Cold fusion has been actively sidelined and even ridiculed (even as research was continuing in governement labs), so it shouldn't surprise anybody that no regular, scientific journals of cold fusion exist. However, that may change sooner rather than later:


Get back to us when it gets beyond the level of sharpening razor blades with pyramid power. The fact is that cold fusion research funds dried up when it turns out that slightly warmed water is the MOST than can be hoped for(and by such tiny fractions of a degree that serious doubt is reasonable that there is any effect at all.. Research funds are the life's blood of physics, so I stand by my characterization of Jones as a FAILURE(no funds=dead end job).

'Let's not confuse noise with signal'.

QUOTE (->
QUOTE
Cold fusion has been actively sidelined and even ridiculed (even as research was continuing in governement labs), so it shouldn't surprise anybody that no regular, scientific journals of cold fusion exist. However, that may change sooner rather than later:


Get back to us when it gets beyond the level of sharpening razor blades with pyramid power. The fact is that cold fusion research funds dried up when it turns out that slightly warmed water is the MOST than can be hoped for(and by such tiny fractions of a degree that serious doubt is reasonable that there is any effect at all.. Research funds are the life's blood of physics, so I stand by my characterization of Jones as a FAILURE(no funds=dead end job).

'Let's not confuse noise with signal'.

I sure do hope, though, that the heavyweights at ae911truth.org will take up the challenge to nail this down.


Any engineer taken in by the pseudo-scientific religion of the Conspiracy Theorists is, by definition, not a heavyweight.

Grumpy cool.gif
metamars
QUOTE (adoucette+May 31 2007, 08:26 PM)
As I said references by YOU to Calladine & English will be IGNORED until you can show HOW AND WHY they should be considered relevant to the issue under discussion.

Such as:



So what is the actual BASIS of your claim "in spite of works..."

Arthur

Use the search function for my previous posts on this subject.
Grumpy
newton

QUOTE
here is something that pope grumpy has decreed 'impossible' because he used thermite in vietnam fourty years ago.


Here is what I ACTUALLY SAID...

QUOTE (->
QUOTE
here is something that pope grumpy has decreed 'impossible' because he used thermite in vietnam fourty years ago.


Here is what I ACTUALLY SAID...

But it will not cut a steel beam in a horizontal direction on it's own, it acts strictly in a vertical direction. That is why real demolition teams NEVER use it to bring down steel structures(except in lances to manually cut beams with a stream of oxygen or compressed air).

There is a patent for a heavy, bulky refractory trough which is meant to contain the reaction and direct it sideways, but no one to my knowledge has ever made one, and of the thousands that would be necessary to bring down a building, not one has been found.


So you lied, I did say there were devices to direct the thermite sideways. Everything I said about thermite is absolutely true.

So where are all of these "heavy, bulky refractory trough(s) which is(are) meant to contain the reaction and direct it sideways"??? Not one of them was found!!!

Grumpy mad.gif
metamars
QUOTE (David B. Benson+May 31 2007, 08:59 PM)
(3) Is Hook's Law reasonable? It is a phenomenological constitutive equation, not derived from first principles. The crush-down equation is a constitutive equation derived from first principles.


Yes, Hooke's Law is reasonable. Also easily tested.

As you know, a good scientific theory must be falsifiable. How can you test your theory? As far as I can tell, only by comparing with an FEA analysis - physical tests are out of the question.

Well, perhaps on a scaled down version. Scaling rules were the ultimate purpose of Calladine and English. However, I find it hard to believe that any reasonable scale model could not more easily be replicated on a computer.

Which raises an interesting question. Can computer software 'widgets', used in an FEA model, be modified as per scaling laws derived from research on physical apparati, such as investigated by Calladine and English? If so, that might radically reduce the computational complexity.

Can't believe I didn't think of this, earlier. Thanks for asking this question.


QUOTE

(4) Hook's Law is a first approximation and is used all the time. It is more than just suggestive and I claim the same holds for the crush-down equation.


Had it only been observed for half of a cycle on a single spring, it would not be more than suggestive.

When I was in college, somebody claimed to have discovered a magnetic monopole based on a single event. Guess what? Nobody believes that, today.

QUOTE (->
QUOTE

(4) Hook's Law is a first approximation and is used all the time. It is more than just suggestive and I claim the same holds for the crush-down equation.


Had it only been observed for half of a cycle on a single spring, it would not be more than suggestive.

When I was in college, somebody claimed to have discovered a magnetic monopole based on a single event. Guess what? Nobody believes that, today.


(5) (a) No CD evidence at all. (cool.gif Impact studies are irrelevant to collapse progression. As I posted about earlier, they are also irrelevant to collapse initiation. © No corrections are necessary.


You're lying. Bald assertion is a propaganda technique. Why not stick to rational arguments?


QUOTE

The crush-down equation matches the data very well.


Your faith in unfalsifiable models is duly noted. Have you considered becoming a big bang cosmologist?


QUOTE (->
QUOTE

The crush-down equation matches the data very well.


Your faith in unfalsifiable models is duly noted. Have you considered becoming a big bang cosmologist?



(6) You can obtain a modern FEA-style computer program from Applied Science Inc. Their advertising claims it can handle progressive collapse. Go to it. But the Greening and B & V analyses fit the data so these cannot be way off.


If this is the same program that adoucette posted about, I have already posted a reference on the stj911 forum. I will do so at the ae911truth web site, also.

QUOTE

(7) Got it now?  dry.gif


I would put the same question to you.
David B. Benson
QUOTE (metamars+May 31 2007, 11:30 PM)
As you know, a good scientific theory must be falsifiable. How can you test your theory?

Why not stick to rational arguments?

I did 'test' it. Twice. Very good fit to the data. Both times.

I always attempt to use rational arguments and I never tell lies (although, of course, sometimes I make mistakes, like everyone else.)

I assert, based on looking at a considerable body of material, for about 1.5 years now, that there is no evidence of CD. Nobody has produced any, even though some of them irrationally want it to be present.

I assert that collapse initiation did not occur through impact events. As I previously posted, the first impact in the core, for WTC 1, occurred at 1.8+ seconds with an impact speed of about 11.7 m/s when the top block, having shoved the 3 story tall core column members ought of the way, impacted the next set of column members down. Furthermore, assuming perfection, the eccentricity was enough so that the critical load is only 0.91 of that for eccentricity 0. As a sudden load of infinite duration, general grounds show that the critical load is only 1/2 that for quasi-static loads. So the core columns could only handle about 45% of quasi-static load. But at 11.7 m/s, the kinetic energy is more than 100-fold larger than the load which buckled the first set of core column members! KAPOW!

No corrections are necessary for collapse progression because all that we have is the video evidence plus now, a value for E1 of 510 MJ. Nobody has yet found plausible means of consuming so much energy during the first few seconds of collapse. A bit slow for much concrete comminution. So slow that air resistance and movement is at most 5% of the total. All I can posit is crushing the trusses fairly flat plus destroying the core. Any other ideas? huh.gif
adoucette
QUOTE (metamars+May 31 2007, 06:10 PM)
Use the search function for my previous posts on this subject.

laugh.gif laugh.gif laugh.gif

As expected.

Arthur
David B. Benson
QUOTE (metamars+May 31 2007, 11:30 PM)
As you know, a good scientific theory must be falsifiable. How can you test your theory?

Falsifiability was Sir Karl Popper's contribution. Turns out to be too strong for many parts of science. A better criterion is testability or, sometimes, just comparability to see which of two competing hypothesis better explains the data.

You must have missed the posts where I determined, via Bayes factors, that the crush-down equation explains the data much better than the hypothesis of free fall due to the unimpeded force of gravity. The units are said to be bans. Here are the results:

WTC 1: 5.5 bans
WTC 2: 9.8 bans

Sir Harold Jeffreys set the criterion for the weight of the evidence being very strongly in favor of the better hypothesis as at least 2.2 bans. By this criterion, the weight of the evidence very strongly favors crush-down over free fall.

I also offered to compare, via Bayes factors, the crush-down equation against any other hypothesis that anybody cared to bring forth. Nobody took me up on the offer. sad.gif
3bodyproblem
QUOTE (adoucette+May 31 2007, 10:28 PM)
The core column dimensions changed as they went up but AFAIK not the overall core dimensions.

See NIST NCSTAR 1-5G appendix B.

Arthur

I cannot find reference to the paper that indicated the core dimensions were reduced, I'm not sure where i saw that? In that case, we can safely assume the core dimensions remained at 86x183 feet. Thank you for the link, I must admit I have not read ALL of the NIST report as this point, and it helps to have proper links.
3bodyproblem
QUOTE (David B. Benson+May 31 2007, 10:40 PM)
Using the data posted on earlier incarnations of this thread by NEU-FONZE, I used the Bazant & Verdure crush-down equation to find that value of E1 which best fits the data. I used the correct mass for the upper portion of both towers as given in NCSTAR1-6D.

E1 = 510 MJ

which is less than Greening's estimate, which was about 600--800 MJ, if I remember correctly.

But note that less than 4% of that energy was consumed in destroying the truss seats. You'll have to look at other means to use up the remaining energy.

A large amount of energy would be dissipated into the dust cloud, plenty of energy for pulverization, and according to reports there was a surplus of energy in the pile weeks later in the form of heat. It would be very hard to disprove any of these claims and relatively simple to prove. Relatively.
I should probably research this more on this forum before i unnecessarily duplicate someones work. Thanks again.
forthetrees
QUOTE (David B. Benson+May 31 2007, 09:18 PM)
.... Otherwise, you probably want a copy of Greening's "Energy Transfer" paper, available from the 911Myths sire [sic], and the ...



Calling Dr. Freud on this one. Typo, or something deeper?

Actually, just some thin skinned chain yanking on my part. Wish I was a better person and didn't feel the need to attempt cheap payback shots like this, but what the heck. rolleyes.gif
Pierre-Normand
The new site Architects & Engineers for 9/11 Truth was obligated to scrap its discussion forum. From now on, the new forum will be open to members only. The reason: it had been infiltrated by shills disguised as "intelligent and honest" debaters.

I provide more details here:

http://www.democraticunderground.com/discu...&mesg_id=158427
wcelliott
QUOTE
The reason: it had been infiltrated by shills disguised as "intelligent and honest" debaters.


Or, more likely, people who knew what they were talking about were making too many good points.
Pierre-Normand
QUOTE (wcelliott+Jun 1 2007, 04:37 AM)
Or, more likely, people who knew what they were talking about were making too many good points.


Yes, perhaps, but believe it or not, that was actually one reason offered by Gage:

"It is an unfortunate reality that there are those who prefer to spread negativity and cause problems under the guise of honest and intelligent discussion and debate."
Pierre-Normand
QUOTE (3bodyproblem+Jun 1 2007, 03:20 AM)
A large amount of energy would be dissipated into the dust cloud, plenty of energy for pulverization, and according to reports there was a surplus of energy in the pile weeks later in the form of heat. It would be very hard to disprove any of these claims and relatively simple to prove. Relatively.
  I should probably research this more on this forum before i unnecessarily duplicate someones work. Thanks again.

In his original paper Greening spits the energy required to remove one floor's supports (E1) from the energy required to fracture the concrete. This makes sense. Inelastic collisions consume energy. This energy just is the amount of kinetic energy lost in reducing to zero the relative velocity of the two impacting masses. This energy (let it be E2) is constant regardless of the value of E1 (assuming E1 << E2). Then you further have E3 the remaining kinetic energy of the falling pile just before it reaches the ground. (I leave out the crush-up phase in what I assume to be a simplified two-stage collapse)

It seems to me that E2 and E3 are the main contributors for the fracture of concrete comminution, production of heat, etc.

I am a bit unclear on how to partition the different components of E1. If it were the case that E1 is just slightly larger that the KE of the falling mass, then the floor being hit would not yield and all of the spent KE would go into producing heat, fracture, plastic deformation of trusses, etc. And likewise, if E1 is just slightly lower than KE, then most of it would go into the same sinks... (Ooops!) Now, I've just changed my view!

The amount of spent KE just can't be very close to E1! The proportion in which this KE is being split between the task of removing the support structure and the task of crushing the concrete (etc.) can only vary infinitesimally between the limit cases where KE approaches the sum E1+E2 either from below or from above. So the assumption that the comminution energy comes mainly from E2 and very little from E1 is not warranted.

Let me redefine E2* ("inertial resistance") to be the theoretical value for the kinetic energy lost in a perfect inelastic collision without external forces. This is computed assuming only conservation of momentum and the absence of structural support. Then E1* is now understood to be the _additionnal_ energy required when the floor must be disconnected -- in addition, that is, to the E2* theoretical baseline thus defined. E1* thus corresponds to the further KE lost from the upper block after the collision owing to the coupling of the lower floor with the building frame.

I can now get back to David B. Benson's question about the "surplus" use of E1 (or of my E1*) and reconsider your suggestion. I began this post with the intention to dismiss your suggestion on the ground that the pulverization energy comes (mainly) from E2. I can no longer say this. Some of the pulverization that occurs during the floor impacts, and before the collapse front reaches the ground, must come from E1*. That is because, as I just now figured out, there ought to be an overlap between the time intervals dt1 and dt2 during which on the one hand (dt1) the support connections are severed (and columns buckle or fracture) and on the other hand (dt2) the relative velocity of the two impacting masses is reduced to zero. This must signify that part of the energy that goes into comminution (and crushing trusses, heating them up, etc.) must come from E1* as the momentum of the upper mass still is (in part) sunken into the frame. How much? Could it reasonably be the whole ballance David B. Benson found to be unnacounted for?
einsteen
Pierre-Normand,

The E1 has nothing to do with the energy lost in the inelastic collisions. During each collision you have a velocity relation but that already takes into account that energy is lost. The E1 is used between the floor collisions, if E1=0 then the new collapsing mass falls a distance h in air, gets a new speed which follows from the relation

v_down^2=v_up^2 + 2gh

and if E1>0 then 2E1/M_c should be substracted, where M_c is the current collapsing mass at that time.

The nice thing is that DBB told that he in fact empirically determined the value of E1, I've also tried that and created some maple plots and indeed it fits very well for E1=0.6 GJ, but only in the beginning.

My conclusion then is that the weakest zone (that collapses first) got these E1 values and the other floors probably have a higher value.

An other thing that I was thinking about is that the whole E1 model in fact also supports the demolition hypothesis because if you blow away the core in a sequence it becomes much more weaker than the rest and then energy cannot be transferred to the rest of the building and is very nicely lost in the crush of that demolished story.
Pierre-Normand
Hello Einsteen,

I fear that you have misread my post somewhat, and not gotten its point (but I might still misunderstand E1).

QUOTE (einsteen+Jun 1 2007, 11:20 AM)
The E1 has nothing to do with the energy lost in the inelastic collisions

Granted. That is why I labeled this energy E2 (at first, and then E2*) to distinguish it from E1.

QUOTE
During each collision you have a velocity relation but that already takes into account that energy is lost. The E1 is used between the floor collisions, if E1=0 then the new collapsing mass falls a distance h in air, gets a new speed which follows from the relation

v_down^2=v_up^2 + 2gh

Yes, it falls a distance h and pick up the kinetic energy Mgh. That's fine but my issue just is with the energy exchanges during the actual collisions.

QUOTE (->
QUOTE
During each collision you have a velocity relation but that already takes into account that energy is lost. The E1 is used between the floor collisions, if E1=0 then the new collapsing mass falls a distance h in air, gets a new speed which follows from the relation

v_down^2=v_up^2 + 2gh

Yes, it falls a distance h and pick up the kinetic energy Mgh. That's fine but my issue just is with the energy exchanges during the actual collisions.

and if E1>0 then 2E1/M_c should be substracted, where M_c is the current collapsing mass at that time.

Yes, E1 is the energy lost to disconnecting the floor being impacted from its support (M_c being M plus the mass of one storey). I label it E1 following Greening: "In order to answer this question we need to move beyond our simple momentum transfer collision theory and consider how much energy is needed to bring about the collapse of one floor. We call this energy E1."

http://www.911myths.com/WTCREPORT.pdf

So, we seem to be in perfect agreement so far!

QUOTE
An other thing that I was thinking about is that the whole E1 model in fact also supports the demolition hypothesis because if you blow away the core in a sequence it becomes much more weaker than the rest and then energy cannot be transferred to the rest of the building and is very nicely lost in the crush of that demolished story.

Isn't the whole collapse duration quite insensitive on the value of E1?
Capracus
QUOTE (einsteen+Jun 1 2007, 11:20 AM)

An other thing that I was thinking about is that the whole E1 model in fact also supports the demolition hypothesis because if you blow away the core in a sequence it becomes much more weaker than the rest and then energy cannot be transferred to the rest of the building and is very nicely lost in the crush of that demolished story.
Blow away the core in sequence? From the impact zone down? You don't think that the lateral weakness of the core was enough to ensure its failure without explosives?

adoucette
QUOTE (einsteen+Jun 1 2007, 06:20 AM)
An other thing that I was thinking about is that the whole E1 model in fact also supports the demolition hypothesis because if you blow away the core in a sequence it becomes much more weaker than the rest and then energy cannot be transferred to the rest of the building and is very nicely lost in the crush of that demolished story.

Except the model shows there is no need to postulate the need for explosives at all.

So why do you?

Arthur
Malmoesoldier
Grumpy

QUOTE
As much as I like Buffy, as far as I know she knows nothing about fires.


She knows nothing about fires???. She works with Structural Fire Engineering!!!.

QUOTE (->
QUOTE
As much as I like Buffy, as far as I know she knows nothing about fires.


She knows nothing about fires???. She works with Structural Fire Engineering!!!.

Tiny little pea shaped ball, just like your brain.


LOL your brain is veeery tiny. Again you are a LIER. Like i said before they have evidence of molten iron and you cant Dennie it, funny. Witch means there was 1538 C. Now go and make out with john mccain, mark roberts and the holy ones NIST.

QUOTE
No, you can't, nor can a failed cold fusion professor, who suddenly needed another line of work. It's not really a big change, as cold fusion turned out to be another pseudo-scientific con job too.


I know you are stupid dont tell me that in every post. Dont talk *** about someone because they do a simple experiment that shows NIST is lying. You cant Dennie that it WASNT aluminum that came out from the tower, the evidence shows that it wasnt. it CANT glow orange like that, like i explained in my last post.

QUOTE (->
QUOTE
No, you can't, nor can a failed cold fusion professor, who suddenly needed another line of work. It's not really a big change, as cold fusion turned out to be another pseudo-scientific con job too.


I know you are stupid dont tell me that in every post. Dont talk *** about someone because they do a simple experiment that shows NIST is lying. You cant Dennie that it WASNT aluminum that came out from the tower, the evidence shows that it wasnt. it CANT glow orange like that, like i explained in my last post.

Then this professor of pseudo-science is lucky to be alive. If for any reason a thermite reaction had taken place he would at least lost his arm.


No because there couldnt be an thermite reaction. He also debunks a theory in his experiments that said maybe the aluminum and steel could make an thermite reaction, indeed it cant, he dropped molten aluminum onto pre-heated rusted steel. the temperature of the molten aluminum in contact with the rusty iron simply cooled at about 25 C per minute until the aluminum solidified. And there was no reaction when he dropped molten aluminum onto crushed gypsum and concrete (wet or dry) and rusty steel.

Malmoesoldier cool.gif
adoucette
QUOTE (Malmoesoldier+Jun 1 2007, 07:41 AM)

She knows nothing about fires???. She works with Structural Fire Engineering!!!.


I cant "Dennie" it, that has to be one of the best Troother posts in a while.

Clearly shows the level of MATURITY and stunning INTELLECT that the movement attracts.

Rant on Moe, the CT movement certainly deserves YOU.

CLASSIC.

Arthur
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