OK, just a wild thought...
E=MC2, right?
Instead of light squared, what if it's really E=M(CG), where G is the speed of gravity?
Gravity traveling at 299,792,458 m/s
Light traveling at 299,792,458 m/s
What do you think? (besides me being crazy).
What's the point of doing that, you're doing nothing more than a relabelling and you confuse people who use G as the Newtonian Gravity Constant, which would certainly make your equation wrong.
It's like saying "Hey, why don't we stop using '1/2' and start using '2/4' ?" In relavity they are interchangable, but because it seems gravity moves at the speed of light, not light moves at the speed of gravity, we use light speed.
It's like saying "Hey, why don't we stop using '1/2' and start using '2/4' ?" In relavity they are interchangable, but because it seems gravity moves at the speed of light, not light moves at the speed of gravity, we use light speed.
QUOTE (AlphaNumeric+Jan 25 2007, 09:10 AM)
What's the point of doing that, you're doing nothing more than a relabelling and you confuse people who use G as the Newtonian Gravity Constant, which would certainly make your equation wrong.
It's like saying "Hey, why don't we stop using '1/2' and start using '2/4' ?" In relavity they are interchangable, but because it seems gravity moves at the speed of light, not light moves at the speed of gravity, we use light speed.
You're right, of course.
I'll change the constant to something like 'Gs, so as not to confuse.
But if nothing can travel faster than light, how can it be squared?
What happens if you try and solve for either or both sides of the equation?
E=MC2
vs
E=M(CGs)
It's like saying "Hey, why don't we stop using '1/2' and start using '2/4' ?" In relavity they are interchangable, but because it seems gravity moves at the speed of light, not light moves at the speed of gravity, we use light speed.
You're right, of course.
I'll change the constant to something like 'Gs, so as not to confuse.
But if nothing can travel faster than light, how can it be squared?
What happens if you try and solve for either or both sides of the equation?
E=MC2
vs
E=M(CGs)
QUOTE (pinestone+Jan 25 2007, 03:17 PM)
But if nothing can travel faster than light, how can it be squared?
What's that got to do with it? c^2 is not a velocity, it's a proportionality constant between mass and energy. Nothing is moving faster than light, velocity isn't even being considered here, E=mc^2 is for an object at rest anyway.
What's that got to do with it? c^2 is not a velocity, it's a proportionality constant between mass and energy. Nothing is moving faster than light, velocity isn't even being considered here, E=mc^2 is for an object at rest anyway.
QUOTE (AlphaNumeric+Jan 25 2007, 03:00 PM)
What's that got to do with it? c^2 is not a velocity, it's a proportionality constant between mass and energy. Nothing is moving faster than light, velocity isn't even being considered here, E=mc^2 is for an object at rest anyway.
"In mathematics, two quantities are called proportional if they vary in such a way that one of the quantities is a constant multiple of the other, or equivalently if they have a constant ratio." -wiki
You're right, again.
So light has nothing to do with the equation?
I guess it's just a number (constant) to make the formula work.
"In mathematics, two quantities are called proportional if they vary in such a way that one of the quantities is a constant multiple of the other, or equivalently if they have a constant ratio." -wiki
You're right, again.
So light has nothing to do with the equation?
I guess it's just a number (constant) to make the formula work.
E=mc² is derived in special relativity which has a postulate that light is the same speed in any inertial frame. It's from that that the 'c' crops up, so light does come into it.
QUOTE (AlphaNumeric+Jan 25 2007, 05:49 PM)
E=mc² is derived in special relativity which has a postulate that light is the same speed in any inertial frame. It's from that that the 'c' crops up, so light does come into it.
Maybe I'm too dense to grasp your explaination, but you say light is the same speed in any inertial frame :
"A fundamental principle of all physics is the equivalence of inertial reference frames. In practical terms, this equivalence means that scientists living inside an enclosed box moving uniformly cannot detect their motion by any experiment done exclusively inside the box". -wiki
How can light be the same speed in our universe, but not come into the equation?
Can you please explain, or reference somewhere where I can get a clearer definition of how light does not factor into the equation?
Maybe I'm too dense to grasp your explaination, but you say light is the same speed in any inertial frame :
"A fundamental principle of all physics is the equivalence of inertial reference frames. In practical terms, this equivalence means that scientists living inside an enclosed box moving uniformly cannot detect their motion by any experiment done exclusively inside the box". -wiki
How can light be the same speed in our universe, but not come into the equation?
Can you please explain, or reference somewhere where I can get a clearer definition of how light does not factor into the equation?
I think you misread me, I said it does come in there, because light, not some other speed, is the same in every inertial frame.
QUOTE (AlphaNumeric+Jan 25 2007, 08:32 PM)
I think you misread me, I said it does come in there, because light, not some other speed, is the same in every inertial frame.
Thanks. I need to study more about inertial frame, obviously.
I'll be back.
Thanks. I need to study more about inertial frame, obviously.
I'll be back.
If nothing else, pinestone, using the symbol "c" rather than a constant doesn't constrain you to metric units! 
But more meaningfully, it shows that the value isn't just some magic number pulled from out of the air, that there's a relationship between rest energy, mass, and the ultimate velocity... which is itself special because it's the same in all frames.
But more meaningfully, it shows that the value isn't just some magic number pulled from out of the air, that there's a relationship between rest energy, mass, and the ultimate velocity... which is itself special because it's the same in all frames.
QUOTE (NoCleverName+Jan 25 2007, 08:53 PM)
If nothing else, pinestone, using the symbol "c" rather than a constant doesn't constrain you to metric units!
But more meaningfully, it shows that the value isn't just some magic number pulled from out of the air, that there's a relationship between rest energy, mass, and the ultimate velocity... which is itself special because it's the same in all frames.
And the ultimate velocity is C
or C squared?
But more meaningfully, it shows that the value isn't just some magic number pulled from out of the air, that there's a relationship between rest energy, mass, and the ultimate velocity... which is itself special because it's the same in all frames.
And the ultimate velocity is C
or C squared?
That would be C, so far as we know. Squaring it in this equation has more of an implication of area under a curve rather than velocity itself.
Uhhh.
Dear NCN
You have failed to answer the man's question.
consider this ( I'm paraphrasing)
One of the main questions that particle physics needs to answer, and which has gone unexplained far too long is why would the square of the speed of light, be chosen over the square root of the speed of light? In other words, why would one avoid in the analysis, the square root of a number (299792.458) that exists and employ instead the square of that number which does not exist.
For the square root of the speed of light represents a value below the speed of light and therefore may possibly have existence. Whereas, the square of the speed of light represents a value that exceeds the speed of light and is recognized by the same scientists who employ that squared value as not having any possibility of existing, for nothing travels faster than the speed of light. On the one hand, then, scientists deny the existence of anything traveling above the speed of light, yet those same scientists for decades have employed without reservation the square of the speed of light as thought it actually exists.
Dear NCN
You have failed to answer the man's question.
consider this ( I'm paraphrasing)
One of the main questions that particle physics needs to answer, and which has gone unexplained far too long is why would the square of the speed of light, be chosen over the square root of the speed of light? In other words, why would one avoid in the analysis, the square root of a number (299792.458) that exists and employ instead the square of that number which does not exist.
For the square root of the speed of light represents a value below the speed of light and therefore may possibly have existence. Whereas, the square of the speed of light represents a value that exceeds the speed of light and is recognized by the same scientists who employ that squared value as not having any possibility of existing, for nothing travels faster than the speed of light. On the one hand, then, scientists deny the existence of anything traveling above the speed of light, yet those same scientists for decades have employed without reservation the square of the speed of light as thought it actually exists.
The use of the exponent in that equation doesn't have anything to do with c. It is a proportionality factor.
Before you cast aspersions on someone's logic, learn what it is you're talking about.
Before you cast aspersions on someone's logic, learn what it is you're talking about.
QUOTE (dirtnapster+Sep 2 2009, 05:53 PM)
square of the speed of light represents a value that exceeds the speed of light and is recognized by the same scientists who employ that squared value as not having any possibility of existing
The logic doesn't have validity since there will always be numbers bigger than "googol" and "parsec" and "light-year". That invalidates neither measurements nor mathematics based on those numbers.
You are right that scientists seem to want to have it both ways if you say "But wait, a proportion? Where the @#$^^&! did that come from?"
That would be valid and it already has valid answers.
The logic doesn't have validity since there will always be numbers bigger than "googol" and "parsec" and "light-year". That invalidates neither measurements nor mathematics based on those numbers.
You are right that scientists seem to want to have it both ways if you say "But wait, a proportion? Where the @#$^^&! did that come from?"
That would be valid and it already has valid answers.
QUOTE (pinestone+Jan 26 2007, 02:17 PM)
And the ultimate velocity is C
or C squared?
The single most important lesson to learn in physics is to understand what units you are talking about.
E=MC^2 is a bad example to start with but all units on each side of an equation must equal out.
But in this case make sure you understand that velocity is distance divided by time.
Dirtnapster also does not understand usage of units.
There is no such velocity as the speed of light squared.
(despite what some incredibly stupid kids show on Einstein says)
or C squared?
The single most important lesson to learn in physics is to understand what units you are talking about.
E=MC^2 is a bad example to start with but all units on each side of an equation must equal out.
But in this case make sure you understand that velocity is distance divided by time.
Dirtnapster also does not understand usage of units.
There is no such velocity as the speed of light squared.
(despite what some incredibly stupid kids show on Einstein says)
There was a really great NOVA show that was all about E=MC^2. I found some parts of it on Youtube:
Einstein's Big Idea:
http://www.youtube.com/watch?v=jlDnmLUEgEw
http://www.youtube.com/watch?v=uwQeAkC9TmY&feature=related
http://www.youtube.com/watch?v=GRdmwV39Fzk&NR=1
I am trying to hunt up the rest.
Einstein's Big Idea:
http://www.youtube.com/watch?v=jlDnmLUEgEw
http://www.youtube.com/watch?v=uwQeAkC9TmY&feature=related
http://www.youtube.com/watch?v=GRdmwV39Fzk&NR=1
I am trying to hunt up the rest.
To Whom:
I never cast aspersions on anyone's logic. I only said that the man's original question had not been answered. Which it has not. I assume it's NCM's arrogance and inability to formulate a viable answer that provokes such pique.
I never cast aspersions on anyone's logic. I only said that the man's original question had not been answered. Which it has not. I assume it's NCM's arrogance and inability to formulate a viable answer that provokes such pique.
QUOTE (IAMoraes+Sep 3 2009, 01:11 AM)
The logic doesn't have validity since there will always be numbers bigger than "googol" and "parsec" and "light-year". That invalidates neither measurements nor mathematics based on those numbers.
This kind of argument won't hold water because c is a dimensionful constant - in other words it has a unit. I can quite easliy define my units so that the speed of light is greater than a googol, or I dare say greater than a googolplex. Calling something large or small only really makes sense when what you're talking about is dimensionless, for example the number of colours in QCD is something that has no units, it's simply a number.
As for comparing the speed of light to the parsec or the light year, it's like asking whether the Eiffel tower is bigger than 20 mph. It makes no sense whatsoever.
This kind of argument won't hold water because c is a dimensionful constant - in other words it has a unit. I can quite easliy define my units so that the speed of light is greater than a googol, or I dare say greater than a googolplex. Calling something large or small only really makes sense when what you're talking about is dimensionless, for example the number of colours in QCD is something that has no units, it's simply a number.
As for comparing the speed of light to the parsec or the light year, it's like asking whether the Eiffel tower is bigger than 20 mph. It makes no sense whatsoever.
QUOTE (dirtnapster+Sep 3 2009, 03:12 AM)
To Whom:
I never cast aspersions on anyone's logic. I only said that the man's original question had not been answered. Which it has not. I assume it's NCM's arrogance and inability to formulate a viable answer that provokes such pique.
It has been answered.
Ok so it was first answered with a question. But it was a valid answer. Why do it. You get the same results but with more confusion.
And light travels at one light year per year. What is the square of that?
And logic based on ignorance needs to have aspersions cast on it.
And people need to understand what Prometheus is talking about.
Understanding units is even more fundamental than understanding calculus for physics.
I never cast aspersions on anyone's logic. I only said that the man's original question had not been answered. Which it has not. I assume it's NCM's arrogance and inability to formulate a viable answer that provokes such pique.
It has been answered.
Ok so it was first answered with a question. But it was a valid answer. Why do it. You get the same results but with more confusion.
And light travels at one light year per year. What is the square of that?
And logic based on ignorance needs to have aspersions cast on it.
And people need to understand what Prometheus is talking about.
Understanding units is even more fundamental than understanding calculus for physics.
QUOTE (prometheus+Sep 3 2009, 04:25 AM)
comparing the speed of light to the parsec or the light year, it's like asking whether the Eiffel tower is bigger than 20 mph
I am glad I didn't do it.
I am glad I didn't do it.
Wow, from 2007 no less!
I can hardly remember why I answered the way I did save for noting that C times C has nothing to do with a really big velocity in the same way that 3 meters times 2 meters isn't "6 meters". An entirely new thing is being created ... an area, not a longer length.
In the same fashion c squared is not a bigger velocity. The resulting units are not of velocity but of "area divided by time squared" (m/s * m/s= m*m/s^2) ... what ever that means.
That's all I meant ... I have no other insight.
I can hardly remember why I answered the way I did save for noting that C times C has nothing to do with a really big velocity in the same way that 3 meters times 2 meters isn't "6 meters". An entirely new thing is being created ... an area, not a longer length.
In the same fashion c squared is not a bigger velocity. The resulting units are not of velocity but of "area divided by time squared" (m/s * m/s= m*m/s^2) ... what ever that means.
That's all I meant ... I have no other insight.
Another stupid Meem question.
If it's all about "proportion" of mass to energy and an atom is 99.99% empty, how is the "value" even close to proportional? Proportional to what, nothing? What weighs more, a pound a bricks or a pound of "air" (uranium)? Except in this case the "pound" of air (a.k.a. nothing) weighs more like 50 kilotons when split it. How is that even close to being proportional?
If it's all about "proportion" of mass to energy and an atom is 99.99% empty, how is the "value" even close to proportional? Proportional to what, nothing? What weighs more, a pound a bricks or a pound of "air" (uranium)? Except in this case the "pound" of air (a.k.a. nothing) weighs more like 50 kilotons when split it. How is that even close to being proportional?
I think its all relative.
No really!
No really!
QUOTE (dakfe09+Sep 5 2009, 04:18 AM)
I think its all relative.
No really!
I think you're right. It's all relative to "nothing!!"
No really!
I think you're right. It's all relative to "nothing!!"
but then 'nothing' is 'something' right?
Without question ... oops, wrong. It does come with one question, what is it?
its nothing, dont worry about it 
QUOTE (Meem+Sep 5 2009, 04:33 AM)
If it's all about "proportion" of mass to energy and an atom is 99.99% empty, how is the "value" even close to proportional? Proportional to what, nothing? What weighs more, a pound a bricks or a pound of "air" (uranium)? Except in this case the "pound" of air (a.k.a. nothing) weighs more like 50 kilotons when split it. How is that even close to being proportional?
Your post is a little confusing.
1) "kilotons" in this case is the measurement of how much TNT it would require to make an explosion of the same magnitude. It's not an actual weight.
2) When a nuclear bomb detonates, a surprisingly small amount of mass is actually being converted to energy. If your fissile material weighs one pound, the mass that was destroyed would be microscopic.
Your post is a little confusing.
1) "kilotons" in this case is the measurement of how much TNT it would require to make an explosion of the same magnitude. It's not an actual weight.
2) When a nuclear bomb detonates, a surprisingly small amount of mass is actually being converted to energy. If your fissile material weighs one pound, the mass that was destroyed would be microscopic.
My post isn't confusing, you're confused about my post. You get too caught up in your line of thought to get the point. So I don't have a pound of "fizzle" material. I have a electron-microscopic amount of "mass" capable of taking out an entire city +.
How's that for proportional?
How's that for proportional?
QUOTE (Meem+Sep 5 2009, 01:57 PM)
My post isn't confusing, you're confused about my post. You get too caught up in your line of thought to get the point. So I don't have a pound of "fizzle" material. I have a electron-microscopic amount of "mass" capable of taking out an entire city +.
How's that for proportional?
fissile = fissionable
YOU can't even figure out you're talking about.
My point was that in a nuclear detonation, the uranium/plutonium isn't converted into energy. Instead, only subatomic particles are converted into energy.
How's that for proportional?
fissile = fissionable
YOU can't even figure out you're talking about.
My point was that in a nuclear detonation, the uranium/plutonium isn't converted into energy. Instead, only subatomic particles are converted into energy.
Fizzle = your lack of understanding. Which is is fizzling in this remark.
My point was that in a nuclear detonation, the uranium/plutonium isn't converted into energy. Instead, only subatomic particles are converted into energy.
Tell me, all the people that use the "mass" of uranium/plutonium are totally stupid? Are you the mad scientist which has figured out how to extract sub-atomic energy from a more stable source material, like a nickle? There is a enough nuclear energy in a nickle to sail an aircraft carrier around the world in definitely, but the idiots that make them are still using uranium and plutonium rods. According to what you say, they only need a nickel?
Or am I wrong in these wild assumptions of yours, about my vocabulary and understanding?
QUOTE
My point was that in a nuclear detonation, the uranium/plutonium isn't converted into energy. Instead, only subatomic particles are converted into energy.
Tell me, all the people that use the "mass" of uranium/plutonium are totally stupid? Are you the mad scientist which has figured out how to extract sub-atomic energy from a more stable source material, like a nickle? There is a enough nuclear energy in a nickle to sail an aircraft carrier around the world in definitely, but the idiots that make them are still using uranium and plutonium rods. According to what you say, they only need a nickel?
Or am I wrong in these wild assumptions of yours, about my vocabulary and understanding?
QUOTE (Meem+Sep 5 2009, 03:32 PM)
Tell me, all the people that use the "mass" of uranium/plutonium are totally stupid? Are you the mad scientist which has figured out how to extract sub-atomic energy from a more stable source material, like a nickle? There is a enough nuclear energy in a nickle to sail an aircraft carrier around the world in definitely, but the idiots that make them are still using uranium and plutonium rods. According to what you say, they only need a nickel?
Or am I wrong in these wild assumptions of yours, about my vocabulary and understanding?
Are you drunk?
Or am I wrong in these wild assumptions of yours, about my vocabulary and understanding?
Are you drunk?
Do you have beer goggles on?
FBM, I think you are splitting hairs since elemental transmutation does go on and uranium is necessarily lost.
For uranium fission, the products have the same number of neutrons, protons and electrons -- but significant relative motion. Once you cool down the products and bring them in one spot, they mass about 1/5th of an amu than the original nucleus.
Which comes to the point I want to bring out.
This masses of the various isotopes, as reflected on any chart of their weights do not total up to the masses of their electrons, protons and neutrons (Hydrogen-1 is closest and comes within 14ppb of being exact). Even more, there is no "bean-counter" formula which allows you to calculate the mass of an isotope from adding up protons, neutrons and electrons.
So mass, which throughout the development of Newtonian mechanics as a number amenable to "bean counter" math (i.e. simple addition) turns out to be somewhat mysterious. But energy, which is a concept which did not originate with Newton himself, is (to the best of experimental precision) preserved by bean counter math, once the mass-energy equation of relativity is taken into effect: E^2 = (mc^2)^2 + (pc)^2
So E(uranium atom) = E(hot fission products) = E(cold fission products) + 200 MeV, and physics is simple again.
In the same way, fast velocities don't add in our universe like the bean counters and Newton would have it. This has been tested thousands of times each day by everyone from truck drivers to scientists (including truck-driving scientists) who depend on this fact to get from place to place and keep the lights on. But there is a related quantity which does add via addition, rapidity and its multiples. r(v) = (ln(c + v) - ln(c - v))/2 = arctanh(v/c).
And both of these effects are explained (correctly, according to lab measurements) by special relativity -- the simplest way we have to explain the universe when we ignore gravity.
That's all I wanted to say.
For uranium fission, the products have the same number of neutrons, protons and electrons -- but significant relative motion. Once you cool down the products and bring them in one spot, they mass about 1/5th of an amu than the original nucleus.
Which comes to the point I want to bring out.
This masses of the various isotopes, as reflected on any chart of their weights do not total up to the masses of their electrons, protons and neutrons (Hydrogen-1 is closest and comes within 14ppb of being exact). Even more, there is no "bean-counter" formula which allows you to calculate the mass of an isotope from adding up protons, neutrons and electrons.
So mass, which throughout the development of Newtonian mechanics as a number amenable to "bean counter" math (i.e. simple addition) turns out to be somewhat mysterious. But energy, which is a concept which did not originate with Newton himself, is (to the best of experimental precision) preserved by bean counter math, once the mass-energy equation of relativity is taken into effect: E^2 = (mc^2)^2 + (pc)^2
So E(uranium atom) = E(hot fission products) = E(cold fission products) + 200 MeV, and physics is simple again.
In the same way, fast velocities don't add in our universe like the bean counters and Newton would have it. This has been tested thousands of times each day by everyone from truck drivers to scientists (including truck-driving scientists) who depend on this fact to get from place to place and keep the lights on. But there is a related quantity which does add via addition, rapidity and its multiples. r(v) = (ln(c + v) - ln(c - v))/2 = arctanh(v/c).
And both of these effects are explained (correctly, according to lab measurements) by special relativity -- the simplest way we have to explain the universe when we ignore gravity.
That's all I wanted to say.
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