To add comments or start new threads please go to the full version of: How many photons?
PhysForum Science, Physics and Technology Discussion Forums > Relativity, Quantum Mechanics and New Theories > Relativity, Quantum Mechanics, New Theories

Bobbo
How do researchers and scientists determine the quantity of photons they use in an experiment?

Especially:
1. As referenced to demonstrating the photoelectric effect.
2. That they actualy are able to use (identify) a single photon.
Zephir
QUOTE (Bobbo+Sep 8 2006, 04:20 PM)
How do researchers and scientists determine the quantity of photons they use in an experiment? As referenced to demonstrating the photoelectric effect.

The number of photons can be detected by the photoelectric effect, for example - but here are certain practical problems.

At first it's a question of sensitivity: the target electrode should be very small and low capacity for the voltage drop didn't not to disappear in electrostatic noise. But the sensitivity of the existing contemporary devices is able to realize such experiment, it just must be done in repeated arrangement: the electrode will be charged by the small current and discharged by falling photons repeatedly. Such process can be integrated to obtain the average shape of voltage drop corresponding the single photons.

The second problem is even more crucial and it consist in fact, it's not so easy to create the source of the lone photons. At the fist glance, the commons photon sources are non-coherent and multi-spectral. But even at the case you'll use a highly monochromatic & coherent laser light, it's not possible to include the filter to separate single photons. The reason is, the photons are entangled in energetic pulses when passing such filter: the less or more entangled atoms are trapping and radiating the group of photons the same time. Such light pulse isn't able to cause the photoelectric effect in just the similar group of target atoms. By such way, in real conditions the photoelectric effect using a light dimmed by simple optical filter is always collective event. You'll need the special single photon source and Kerr's optical switch to separate the single photons in repeated experiment. Nevertheless, such experiments were done with quantum dots recently, so we can know, such single photon processes can be conducted in experimental arrangement.
Confused2
Hi Bobbo,Zephir,

This is about the double slit experiment with single photons but might be helpful.

http://www.optica.tn.tudelft.nl/education/photons.asp

QUOTE

The light source was a 4 mW He-Ne laser with a wavelength of 632.8 nm. The laser power was lowered with a set of neutral density filters by a factor of about 10-11, so that the flux of photons was of the order of 105 photons/sec, implying that the mean path between the photons was a couple of kilometers.


They're not so much generating single photons as making them further and further apart.

Hope this was of interest.

Best wishes,

-C2.


TRoc
Hi all,


What is a single duality?

Can we really even answer what a single "photon" is, let alone produce one?


From Zephir's link:
QUOTE
"In terms of suppressing multiple photon generation, we’ve achieved an order of magnitude below what you get from a laser," said Martin Ward, a member of the research team from Toshiba Research Europe. "There are other ways of generating single photons, like down-conversion, but this is the first time that strong [multiple photon] suppression from a quantum-dot type source has been demonstrated at telecom wavelengths."


..suppression is not isolating
..averaging is not measuring single entities (from C2's quote using mean time/path)


The omni-valued "photon" is still ill defined after 100 years!

What is the space immediately before and after an electromagnetic vibration doing? By the historic standard of Science, this "phenomenon" should have its' own identity in the Standard Model! The near and far field effects are neither the observer or the observed; that is, it isn't the thing being measured, nor the path of the measurement, IE the target/observer.

This is just space vibrating. Space has orthogonal permittivity & permeability for the EM wave. Part of the wave (less than 1 vibration) will not have both properties, nor the driving, orthogonal force being the normal, full fledged EM wave.

Now place these vibrations a small distance apart; the lead "photons' " tail and the trailing "photons' " nose being spaced the same as either "photons" nose-to-tail measurement. This is the phase relationship. No matter how far apart these are, they will be creating a phase (from the same source), and produce the interference pattern.

The only way to create a single "photon" is by a precise kick to an atom; that precise kick also being a "photon". Is this the chicken / egg question?


T.Roc


Zephir
QUOTE (TRoc+Sep 8 2006, 08:09 PM)
The only way to create a single "photon" is by a precise kick to an atom; that precise kick also being a "photon". Is this the chicken / egg question?

Of course not. You can kick the atom into excited state and then wait for the spontaneous thermal deexcitation followed by radiation. It proceeds with certain probabilities between specific energy levels. In fact, the spontaneous emission is the most common case of atom radiation by far. The kick-off the photon from atom by another photon is so-called stimulated emission used in lasers, in fact a considerably more rare situation (why?)...

User posted image
Bobbo
Thanks all, I'm off to check the links. Be back later. Probably with more questions.
Good Elf
Hi Bobbo, zephir, TRoc, Confused2 et al,

Individual photons can easily be generated. A particular transition between two quantum states will have a specific energy of hf (of absorption), effectively a "hole". The "emission line" that this photon will later instantaneously generate, has a finite width, this is two fold ... it delimits the photon in space and it delimits it in time. Every atom has a "lowest state" of excitation, the ground state. Alternatively you may choose to start from the fully ionized state... your choice in the experiment. In either case the transition will be the lowest available energy transition. The emission of the first photon can be controlled by the exciting radiation because all materials have a "work function". This first emission (and also other emissions) therefore is a "packet". If we are not talking about "stimulated" emission, then when you "kick" a single atom it will gain (relative to our "kicker" frame of reference) kinetic and potential energy as well as momentum (as an exchange photon which could have "any energy" at all). Internally an electron has simultaneously been promoted to the next available shell if the total available energy is greater than this minimum transition energy. Then after a period of time the electron undergoes a transition to a lower state emitting the photon. Since the photon will try and match as closely as possible this energy it received originally, it will emit that photon with a total energy of E=hf in a random direction and the rest of the energy will end up as residual kinetic and potential energy as well as a residual momentum of that atom... all as "recoil" relative to the "kicker" frame of reference. This is because the photon is unique and has no rest mass and cannot carry any additional momentum or energy as do other particles. The sums will balance relativistically for an initial "inertial atom". In practice the experiment need to do things in a non-ideal way... that is where you get into a lot of maths.

A single optical photon is actually easy to measure using the correct apparatus. They "scale" perfectly as the number of photons increase from as little as a single photon a second to as many as you like. Therefore you can easily calculate the number of photons being emitted per second from a source of monochromatic radiation. Stimulated emission is a different process.

Cheers
Nick
QUOTE (TRoc+Sep 8 2006, 05:09 PM)
The only way to create a "photon" is by a precise kick to an atom; that precise kick also being a "photon".


T.Roc

The only way to create a photon is to excite matter. This means radiation has its origin in matter. Matter had to come first if EM radiation or light comes out of it. This is indisputable.
Good Elf
Hi Nick, Bobbo, zephir, TRoc, Confused2 et al,
Go back and read your texts more carefully. All electromagnetic forces are actually expressible as "virtual photons". They do not have a fixed energy and you can't actually individually measure them.. yet without them how do you get radio transmitters? Within a wide range of parameters the photons can be made to be of any frequency (size) you choose depending on purely geometric factors (like the length of a wire).

The electrons that produce these photons can actually come from "pushing" then around many feet in distance and the photons can also be similarly sized as well.

Cheers
Zephir
QUOTE (Good Elf+Sep 9 2006, 06:27 AM)
Go back and read your texts more carefully. All electromagnetic forces are actually expressible as "virtual photons".

We're disputing a "real" photons here, not some virtual non-quantized particles.
The word "photon" (means quanta of energy) isn't usable here.
Good Elf
Hi zephir,

QUOTE (Zephir Posted on Today at 8:05 AM+)
QUOTE (Good Elf @ Sep 9 2006+ 06:27 AM)
Go back and read your texts more carefully. All electromagnetic forces are actually expressible as "virtual photons".
We're disputing a "real" photons here, not some virtual non-quantized particles.
The word "photon" (means quanta of energy) isn't usable here.
I disagree entirely... you are not able to deal with energy processes (conventionally speaking) without recourse to these "non-quantized particles" actually they are just as quantized as any other ... the only difference is they are not "granular" in any strict sense of the word, they can be any energy at all.. that does not mean the same thing. It is a mistake to think you can just "forget about them" in fact this is the source of all the forces since we have shown that three of those forces are unified in electromagnetism and the fourth (gravity) is a "pseudo-force" and may be linked with electromagnetism too.. It beggers the mind when you realize that we have a "complete" theory of particles based on "quanta" and the very forces behind these "particles" have been completely left off the map. This omission has cost science dearly and has come back to "bite" us all. A complete generation who have no idea what is going on.

The matter is not resolved simply by saying that photons are emitted by nuclei or by electron shells. Electromagnetic forces can generate photons of "geometrically" arbitrary size. These are no different in their nature to electronic or sub-nuclear photons, they are just at a different scale (wavelength). Their origin is found squarely in the basic mechanism which generates them ... and indeed the basic truly fundamental mechanism which in theory can generate all particles. This is a form of quantum geometrodynamics... you are dealing with evanescent fields and their short range propagation forming photons. Most people talk about electric and magnetic fields but the reality is these are the 'exchange force carriers" in the Universe, that also means the "forces" in a magnet and in a charged Van der Graff Sphere. The reality is found in Feynman and Wheeler's Nobel Prize winning paper.

Where electronic photons are emitted by shell transitions are of a fixed wavelength we can build suitable electromagnetic radiation fields that spontaneously produce continuous fixed wavelength emission of photons. We do this by a continuous supply of energy through electronic circuits. We employ electrons and their movements in conductive wires to generate quantum particles... photons. In atoms and photoemissive materials we speak of work function, in antennas we are speaking about antenna impedance and radiation resistance which are pure spatial properties. Conventionally and traditionally this is the area of "virtual photons". Alternatively it is the area where my "String Theory" begins. "If anything are strings... everything are strings". Conventional theory (particle theories) must deal with this as particles. It is not possible to derive a full description of electromagnetic theory using QFT. Presently it is not possible to develop a QFT from "classical" theory without those endless quantum postulates.

Remember this ...
User posted image

and also this...
Radiation from a short dipole
and this...
QUOTE
Virtual photons

The electron and nucleon interact by the electromagnetic force, the carrier of this is the virtual photon as has different properties to ordinary photons. Take for example two electrons.  These repel each other due to the electromagnetic force, we say that there is a mediator or exchange particle which is transferred between them, the photon.  If one imagines two ice skaters facing each other and one throws a ball to the other person both skaters will move apart, just as two electrons would repel each other.

When delving inside the proton (or neutron) it is not the electron which actually 'probes' the nucleon but the photon.  An electron gives some of its energy (and so loses some of its momentum) to the photon.  The more momentum which is transferred to the photon, the more energy it has and so the shorter the wavelength of the photon. One can imagine that a longer wavelength photon will only 'see' the whole nucleon and so be elastically scattered, but for shorter wavelength photons it can 'see' the constituents of the nucleon, the quarks inside.  This is why physicists want to build larger and larger accelerators, so that they can see more and more of the structure of particles. 
Virtual photons


I think I explained about the phase of these particles recently being the source of these "forces" and to their direction (LASER ... boson stimulated emission). This is an "inconvenient truth" for QFT. A close examination of the near-field is required to understand the nature of the electromagnetic "force" and the far-field to understand how this "force" is transported. So there are no "forces" but exchange particles which propagate at the speed of light. These all relate to the boson and fermion fields (charge and isospin). These "bosons" (photons) are the product of space time geometry alone. It is my view even charge is a product of pure geometry. As an example look at the Williamson and Van der Mark Paper.
Is the electron a photon with toroidal topology?
It has been found "appropriate" in the past to deal with the near field using only retarded potentials but the advanced potentials (from the future) are the complement of this operation which result in those stable particles we can all see as "bright matter solitons"... stabilized by CPT.

Personally I do not like the theory of "virtual photons" that is why I prefer "String Theory" as the paradigm. Here you have the transition between the nature of real quanta and where they originate from "sampling" energy from the available sources. Quanta are the result of truncation of emission and absorption of electromagnetic process in time... and like all other quantum entities are not "intrinsic" but "environmental attributes".

Cheers
TRoc
Bobbo,


OK, you've got several descriptions of the same thing..

QUOTE
Nick Posted on Yesterday at 3:09 AM
The only way to create a photon is to excite matter.


QUOTE (->
QUOTE
Nick Posted on Yesterday at 3:09 AM
The only way to create a photon is to excite matter.


Zephir Posted on Sep 8 2006, 06:00 PM
You can kick the atom into excited state and then wait for the spontaneous thermal deexcitation followed by radiation.


QUOTE
Good Elf Posted on Yesterday at 3:09 AM
A particular transition between two quantum states will have a specific energy of hf (of absorption), effectively a "hole". The "emission line" that this photon will later instantaneously generate, has a finite width, this is two fold ... it delimits the photon in space and it delimits it in time.


QUOTE (->
QUOTE
Good Elf Posted on Yesterday at 3:09 AM
A particular transition between two quantum states will have a specific energy of hf (of absorption), effectively a "hole". The "emission line" that this photon will later instantaneously generate, has a finite width, this is two fold ... it delimits the photon in space and it delimits it in time.


TRoc Posted on Sep 8 2006, 05:09 PM
The only way to create a single "photon" is by a precise kick to an atom; that precise kick also being a "photon".



You probably knew this already anyway.

However, towards yours questions:

1. As referenced to demonstrating the photoelectric effect.
2. That they actualy are able to use (identify) a single photon.


We also historically have NOT been able to isolate an atom. I, for one, am trying to answer your question within the logical framework of WHAT was going on in Physics at the TIME the idea of the photo-electric effect was put forth, and accepted (because it was the only answer, not because it was the best of several choices).

So, what we have, again, is a STATISTICAL, or probabilistic theory. Light (many "photons") is directed onto a molecule containing MANY "free" electrons", and at some point, a "photon" kicks an electron out of the molecule.

We have an average, large number of photons, hitting a large number of electrons, and 1 pops out. Of course, the theory is sound within these guidelines. They have NOT been updated with an absolute procedure; 1 photon shot at 1 H atom containing 1 electron, with the predicted effect happening.

It sounds like you will have to judge for yourself, because their is some disagreement among us. I will repeat my stance, which no one has over-turned by logical, or empirical response.

..suppression is not isolating
..averaging is not measuring single entities


QUOTE
Good Elf Posted on Yesterday at 3:09 AM
A single optical photon is actually easy to measure using the correct apparatus. They "scale" perfectly as the number of photons increase from as little as a single photon a second to as many as you like. Therefore you can easily calculate the number of photons being emitted per second from a source of monochromatic radiation.


"photons" per second is a RATE, similar to speed. If I say I am driving 50 miles per hour, you can neither deduce that I have gone only 1 mile, nor that I have been driving for 1 hour.

The bottom line is that ENERGY is going into the apparatus at a CONTINUOUS rate, and controlled so that it also comes out that way. The WHOLE number of "photons" involved is certainly more than 1.

Energy MUST be conserved, it is neither created nor destroyed.

The answer is logically, and absolutely, that we can not "create" 1 "photon". This is not the same as saying that 1 "photon" can not exist, by the process that we all mentioned.

The problem is, as was pointed out, we have NO CONTROL over where the "reacting photon" will go, so we have no real way of "catching" it in the act. Again, stimulated emission is different, but certainly containing many orders of magnitude more than 1 photon.


Just for good measure:

"photons" & "virtual photons" : redundant, redundant, REdundant!

QUOTE (->
QUOTE
Good Elf Posted on Yesterday at 3:09 AM
A single optical photon is actually easy to measure using the correct apparatus. They "scale" perfectly as the number of photons increase from as little as a single photon a second to as many as you like. Therefore you can easily calculate the number of photons being emitted per second from a source of monochromatic radiation.


"photons" per second is a RATE, similar to speed. If I say I am driving 50 miles per hour, you can neither deduce that I have gone only 1 mile, nor that I have been driving for 1 hour.

The bottom line is that ENERGY is going into the apparatus at a CONTINUOUS rate, and controlled so that it also comes out that way. The WHOLE number of "photons" involved is certainly more than 1.

Energy MUST be conserved, it is neither created nor destroyed.

The answer is logically, and absolutely, that we can not "create" 1 "photon". This is not the same as saying that 1 "photon" can not exist, by the process that we all mentioned.

The problem is, as was pointed out, we have NO CONTROL over where the "reacting photon" will go, so we have no real way of "catching" it in the act. Again, stimulated emission is different, but certainly containing many orders of magnitude more than 1 photon.


Just for good measure:

"photons" & "virtual photons" : redundant, redundant, REdundant!

From Wikipedia, the free encyclopedia
(Redirected from Virtual photons)

In physics, a virtual particle is a particle-like abstraction used in some models of quantum field theory. Virtual particles exhibit some of the phenomena that real particles do such as conservation of charge. Nevertheless they are unobservable by their very definition, and furthermore do not respect some of the most fundamental laws associated with physical particles. The concept of virtual particles necessarily arises in the perturbation theory of quantum field theory where interactions between real particles are described in terms of exchanges of virtual particles. Any process involving virtual particles admits a schematic representation known as a Feynman diagram which facilitates understanding of calculations.

A virtual particle is one that does not obey the  relationship. In other words, their kinetic energy may not have the usual relationship to velocity, indeed, it can be negative. The probability amplitude for them to exist tends to be cancelled out by destructive interference over longer distances and times. They can be considered a manifestation of quantum tunnelling.

The term is rather loose and vaguely defined, in the sense that it clings to a rather incorrect view that the world is somehow made up of "real particles": it is not; rather, "real particles" are more accurately understood to be excitations of the underlying quantum fields. As such, virtual particles are also excitations of the underlying fields, but are "temporary" in the sense that they appear in calculations, but never as indexes to the scattering matrix (i.e., they never appear as the observable inputs and outputs of the physical process being modeled). In this sense, virtual particles are an artifact of perturbation theory, and do not appear in a nonperturbative treatment. As such, their existence is questionable; however, the term is useful in informal, casual conversation, or in rendering concepts into layman's terms.


Pick out a few telling snips:

"a particle-like abstraction used in some models of quantum field theory"

SOME models of a partial solution. Not the whole truth yet.

"Nevertheless they are unobservable by their very definition, and furthermore do not respect some of the most fundamental laws associated with physical particles."

What, not obeying FUNDAMENTAL LAWS of Physics?? Either those fundamental laws are wrong, or the idea of "virtual particles", or both.

"Any process involving virtual particles admits a schematic representation known as a Feynman diagram which facilitates understanding of calculations."

Feynman, while a great Physicist, DID NOT solve our problem. Just another partial view with limited value. So his diagrams are NOT fundamental.

".."real particles" are more accurately understood to be excitations of the underlying quantum fields. As such, virtual particles are also excitations of the underlying fields, but are "temporary" in the sense that they appear in calculations, but never as indexes to the scattering matrix (i.e., they never appear as the observable inputs and outputs of the physical process being modeled)."

Gee, sounds like what I said "What is the space immediately before and after an electromagnetic vibration doing? By the historic standard of Science, this "phenomenon" should have its' own identity in the Standard Model! The near and far field effects are neither the observer or the observed; that is, it isn't the thing being measured, nor the path of the measurement, IE the target/observer."

They're not quite ready to give the "virtual particle" a spot in the line-up. The subtle harmonic beat frequencies of the vibration can not sustain themselves outside of the interaction area. Again, "particle & virtual particle": REdundant! They are just manifestations of the vibrating fields.


ciao!

T.Roc





Good Elf
Hi TRoc,

QUOTE (TRoc Posted on Yesterday at 5:55 PM+)
"photons" per second is a RATE, similar to speed. If I say I am driving 50 miles per hour, you can neither deduce that I have gone only 1 mile, nor that I have been driving for 1 hour.
Sorry, you have misinterpreted me TRoc. No "speed" is intended. We know all photons travel at the speed of light. For the purpose of this "gedanken experiment" electrons for instance do have specific velocities and the double slit experiment needs to be performed with electrons too (you will get a similar result with shorter wavelengths). This "particle" experiment requires the "science" of velocity selection. Lets not go down that path just now but it is not impossible though.

Rates are "counts" per second. There are special devices that can actually count actual photon impacts and their spatial position on a special plate. These are the electronic equivalent of a Cadmium Sulfide Scintillation Screen. Each photon when it impacts on the surface of the detector "hits" a special scintillation crystal (of Potassium Iodide) that emits a single photoelectric electron. Directly behind the crystal there is a "Cesium Microchannel Plate" ... a multi channel photon multiplier unit which effectively amplifies the single photon into a torrent of electrons down the vertical channels of the plate. You then have a XY display of the data of the photons striking the surface of the plate in time and position. The "simple" single version of this is like the one found here...
http://en.wikipedia.org/wiki/Photo_multiplier
... only the more sophisticated variety have military applications and are usually termed "Starlight Scopes" and other laboratory versions are called Fourier Transform Plane Detectors. These are the same as the starlight scopes with an 2D image semiconductor photo sensor array at the back ... instead of your eye... bang bang! wink.gif

Here is one such device being used in the Delayed Choice Quantum Eraser Experiment (a variation of the Young's Two slit Interference experiment)...
A Delayed Choice Quantum Eraser: by Yoon-Ho Kim, R. Yu, S.P. Kulik, Y.H. Shih, and Marlon O. Scully
It is the one that produces the nice graphs as see at the bottom of the article. Spatial position and "coincidence" can be determined using the appropriate gated circuits.

Cheers
TRoc
GE, Bobbo, all..


QUOTE (TRoc Posted on Yesterday at 5:55 PM)
"photons" per second is a RATE, similar to speed. If I say I am driving 50 miles per hour, you can neither deduce that I have gone only 1 mile, nor that I have been driving for 1 hour.

Sorry, you have misinterpreted me TRoc. No "speed" is intended. We know all photons travel at the speed of light.


Come on Good Elf, did you really think that's what I meant? I used the word "similar" to alert the use of analogy in the statement to follow. Clearly (I think) I am saying that a 1 photon per second rate is a 1 photon per second AVERAGE rate in the measuring device. Nothing about speed in regards to this topic is being brought up. Read the end of the statement again:

".. you can neither deduce that I have gone only 1 mile, nor that I have been driving for 1 hour. "

So, you can neither deduce that you have measured only 1 photon, nor that you have been measuring for 1 second.


At any rate (hehe), your photomultiplier is breaking my rule: energy is being ADDED to the measuring system DURING the measurement.

QUOTE
(Wikipedia)
The electron multiplier consists of a number of electrodes, called dynodes. Each dynode is held at a more positive voltage than the previous one. The electrons leave the photocathode, having the energy of the incoming photon. As they move towards the first dynode they are accelerated by the electric field and arrive with much greater energy.


They also are (usually) using a laser: many photons, reduced as much as possible, but not all the way down to 1.



T.Roc


Good Elf
Hi TRoc,

I am only trying to answer the original question...
QUOTE (Bobbo Posted: Sep 8 2006+ 01:20 PM)
How do researchers and scientists determine the quantity of photons they use in an experiment?

Especially:
1. As referenced to demonstrating the photoelectric effect.
2. That they actualy are able to use (identify) a single photon.
He he he! I think I have my wires crossed here or something .... the question is only how do we use and measure that single photon at a time. You have slightly modified the problem into actually producing a single photon at a time. I really do not care about that as long as I can "produce" a single photon of light at a particular frequency and count it and where it falls on a screen as in the dual slit experiment... this is just a highly attenuated source of light.
QUOTE (TRoc Posted: Sep 8 2006+ 05:09 PM)
Can we really even answer what a single "photon" is, let alone produce one? [....] The only way to create a single "photon" is by a precise kick to an atom; that precise kick also being a "photon". Is this the chicken / egg question?
This is a much wider problem than the question. I am unsure Bobbo wants to know the answer to this wider question or not? Photons are definite particles (as far as you would like to go on that one)... each photon has integer boson spin quanta as well as carrying a single quanta of energy equal to hf. They travel at the speed of light and spread... this is a pure geometric factor and the way in which a "particle" responds to the geometry of the space it finds itself in. Being a boson they are a little different to other particles in that a large number of the same particle can occupy the same space at the same time ... unlike fermions... but all particles in Supersymmetry Theory has a boson sparticle superpartener. I understand that standard theory has a chronic inability to see these everywhere like I do but they are simply the expression of an equivalent fermion "somewhere else"... in reciprocal space.

All right if you do not like this idea if we just keep to the "standard interpretation" we can down convert individual photons into pairs. Each individual is quantum entangled with the other. Another phenomena where a single photon can be "trapped" in Circuit Quantum Electrodynamics where a single photon can be locked in a "loop" forever repeating its own emission and absorption from a "synthetic atom" with a single quantum transition eigen value. Here you can study a single photon till the cows come home... well in "nuclear times" anyway...
Circuit quantum electrodynamics: Coherent coupling of a single photon to a Cooper pair box
Featured in Nature (September 9, 2004).

I may be missing something here though... could you explain what it is "specifically" you are trying to point out to me?

Cheers
yquantum
Good Elf, et al,

Good Elf well said but you have proven your credentials on this forum by your support to so many, and that speaks volumes. The site below should give all the information needed to support you in what you have stated.

Take care. wink.gif

http://www.sns.gov/pac05/pac05_abstracts_w...ns%20femilab%22

ciao_
yquantum

TRoc
Hi GE, & all ..


You're right, I am trying to throw 'producing' s single photon into the equation, because I feel that that is crucial to obtaining the whole picture.

How can we expect to devise a simple explanation for the entire system if we are not accurate in our basic counts?


Same story ..

QUOTE
Strong Coupling of a Single Microwave Photon to a Superconducting Qubit
Using Circuit Quantum Electrodynamics
by
A. Wallraff, D. Schuster, A. Blais, L. Frunzio, R.-S. Huang, J. Majer, S. Kumar,
S. M. Girvin, and R. J. Schoelkopf


".. a single superconducting qubit (quantum bit or artificial ‘atom’). The artificial ‘atom’ actually consists of roughly 1 billion aluminum atoms .."



They start off by a "single" artificial atom (qubit) consisting of 1 billion atoms.

Then they alter the "single" photon definition used in the title.


QUOTE (->
QUOTE
Strong Coupling of a Single Microwave Photon to a Superconducting Qubit
Using Circuit Quantum Electrodynamics
by
A. Wallraff, D. Schuster, A. Blais, L. Frunzio, R.-S. Huang, J. Majer, S. Kumar,
S. M. Girvin, and R. J. Schoelkopf


".. a single superconducting qubit (quantum bit or artificial ‘atom’). The artificial ‘atom’ actually consists of roughly 1 billion aluminum atoms .."



They start off by a "single" artificial atom (qubit) consisting of 1 billion atoms.

Then they alter the "single" photon definition used in the title.


"The energy of the microwave photons is correspondingly 100,000 times lower and hence these pusillanimous particles are extremely difficult to detect on an individual basis. The electromagnetic energy of a single one of these photons is roughly equivalent in magnitude to the sound energy impinging on your ear if you are standing in Los Angeles and someone in New York drops a pin onto a table."


QUOTE
"[The microwaves are not detected as individual photons; it takes about 30 photons to obtain a measurable signal, but this is not a serious limitation in the present experiment.]"



I agree, not a limitation for that experiment. Indeed, maybe not for any of the current models, so maybe I am just splitting hairs. dry.gif


QUOTE (->
QUOTE
"[The microwaves are not detected as individual photons; it takes about 30 photons to obtain a measurable signal, but this is not a serious limitation in the present experiment.]"



I agree, not a limitation for that experiment. Indeed, maybe not for any of the current models, so maybe I am just splitting hairs. dry.gif


"When the qubit is present in the cavity and its excitation energy is tuned to match the resonance frequency of the microwave cavity (something that can be conveniently done with small voltages and magnetic fields applied to the qubit), .."



Again, energy is added (through the back door!). Does this energy come in quanta's too, or not? So, the net result is yet more "photons" in the cavity.


QUOTE
"When the input microwave power is a miniscule 10-17 watts, there is on average one photon in the cavity."



'averages' .. I would prefer something more precise.


QUOTE (->
QUOTE
"When the input microwave power is a miniscule 10-17 watts, there is on average one photon in the cavity."



'averages' .. I would prefer something more precise.


"Hence at the lowest drive power there is still one photon passing through the cavity about every 10 microseconds which is often enough to register a significant signal in the low-noise amplifier, even though it cannot detect the photons individually.]"



"often enough to register a significant signal .. even though it cannot detect the photons individually."

probably says it all right there.


QUOTE
"Based on the results of the present experiment we estimate that the average number of thermally produced photons in the cavity is well below 0.1."



This is very good, but does not completely (100%) block out black body radiation seeping into the cavity during the experiment. Add a couple more photons. wink.gif




ciao!

T.Roc

Good Elf
Hi Yquantum,

Sorry I have not been in touch lately. Thanks for the document... Not quite sure what I will find there. I hope the family is well and that your work at Cern is proceeding well. I realize you are not able to divert your attentions to everything happening on the Forum. Still I am amazed that you still find time to bob in and make a contribution. I really appreciate that you have been able to do this. A small question... what do you think about the NASA discovery of "Dark Matter"?
1E 0657-56: NASA Finds Direct Proof of Dark Matter
Is dark matter composed of "sterile neutrinos" or something else? Are there neutrinos with little or no kinetic energy or do these fermions form (Bose-Einstein) boson clouds? Is it possible "dark matter" is matter in other dimensions with gravity "seeping" through. Surely these issues affect the outcomes at Cern as well. I imagine that it also affects the hunt for the Higgs too.

TRoc's question seems to be very searching... the only problem is what he is searching for? The "artificial atom" being made of a billion atoms is not the issue here, I believe it is the production of single photons.

Cheers and all the best wishes... I will say some more soon.
Bobbo
Wow! The question seems to have stirred up an old conflict of ideas. I had thought the wave idea was long abandoned and the theories were more to the center of the photon as a particle.

Thanks for the links. I have to say, I'm a bit less impressed with the experiments than I had thought I'd be. They use mechanical and electronic filters, amplifiers, mirrors and uncalibrated black box shields. I can't help but believe that these all add noise. And I remember no mention of doing the work in a vacuum. I had thought the equipment and the techniques would have been vastly improved over the last several decades.

I guess I was hoping that the issue was pretty well settled and better tools were available. Not going to be that easy, is it?

I tend to lump the developments in solar energy, LEDs, light amplification devices, stealth technology, and even data storage into the same pot. I believe all this is closely related (aside from the obvious) and that it must point to a common root structure and behavior for the photon.

One of my favorite "conspiracy theories" is that the research done on solar energy produced the stealth technology, and that's what killed solar. What I'm seeing now tells me that there may be more "out there" than "they" are telling us. wink.gif I suppose we have to expect that if there are significant military or commercial applications based on an understanding of the photon (or anything else for that matter), that it wouldn't be made public.

My ultimate goal in asking the question was to determine if the tools were available to even theorize developing accurate photoelectric data for each of the elements across a wide emr spectrum. I don't think we're there yet.

Again, I really appreciate all the input. Thanks to everyone.
TRoc
GE,


I'm just searching for a better Science.

You said "The "artificial atom" being made of a billion atoms is not the issue here, I believe it is the production of single photons." That is true enough; the reason I started with that statement was to show clearly how the paper used the words " a single cubit (atom), and then, IN THE FIRST LINE of the paper, redefine that "single" atom to = 1 BILLION atoms. That's an absolutely huge difference, and a blatant mis-statement.

Then they did the exact same thing with the term "single photon". I offered 6 other quotes from that paper that support my stance, and you ignored them. I won't repeat them all here, except for the 2 that say, VERBATIM, that they can not measure 1 photon.

[QUOTE] "Strong Coupling of a Single Microwave Photon to a Superconducting Qubit Using Circuit Quantum Electrodynamics "
by
A. Wallraff, D. Schuster, A. Blais, L. Frunzio, R.-S. Huang, J. Majer, S. Kumar,
S. M. Girvin, and R. J. Schoelkopf

"[The microwaves are not detected as individual photons; it takes about 30 photons to obtain a measurable signal, but this is not a serious limitation in the present experiment.]"

"[Hence at the lowest drive power there is still one photon passing through the cavity about every 10 microseconds which is often enough to register a significant signal in the low-noise amplifier, even though it cannot detect the photons individually.]"

(emphasis added)


So, Bobbo, you're right, it's not going to be easy.

smile.gif


Regards,

T.Roc


RealityCheck
.
Hi Bobbo, Troc, Zephir, GE and everyone!

Bobbo: My apologies for interrupting. For your information, I have just posted some TOE project 'implications' in the PHILOSOPHY thread; and will be posting the rest of the implications for the other 'associate' threads in the Cosmology Special Project sub-forum. Once I have done that (TOMMOROW if all goes OK), I will be spending a week or so finalising some long-delayed work on ELECTROMAGNETISM/PHOTONIC NATURE/STRUCTURE that I promised to discuss with GE, Zephir, TRoc before I posted it in the appropriate TOE 'associate' thread. It should be both original and enlightening.....so don't 'finalise' your own enquiries/conclusions until you have seen what eventuates after GE, Zephir, TRoc have 'peer reviewed' what I promised to submit-to/discuss-with them prior to posting. Cheers, and 'see ya round', Bobbo!

And Cheers till I contact you soon GE, Zeph, TRoc!

RealityCheck.
.
Good Elf
Hi RealityCheck, Yquantum, Bobbo, Troc, Zephir et al

I will go and have a look at what you have there RC... thanks for that. Back to Bobbo and TRoc...

TRoc I am not arguing with the points you raised but obviously you seem to be objecting to the mechanism under which photons are produced... that is the "real" question ... is it? Now the emission of a single photon is relatively simple to detect as a single event, obviously it depends on the amount of energy the individual photon carries. A microwave photon is harder to detect than an optical photon because of not only the size (you know Heisenberg's Uncertainty Principle) and the incredibly more feeble these things are individually. We can produce copious coherent optical photons "easily" (LASER) thus it is "easy" to reduce the intensity of this "beam" until only a couple of photons a minute are detected. We can actually see individual flashes on a screen (I almost mean that literally)... the human eye is only about 1/2 of a scale of magnitude away from this level of detection with our native unaided eyes. Most assuredly we can "easily" detect optical photons singly with sensitive photodetectors.

Our technology has been able to produce coherent photons at the Microwave, radio and longer wavelengths in copious numbers too but because of the energy individually of these emissions and their incredible physical size (which is inversely proportional to the energy) and to the spreading attribute they are harder to separate. Remember the Omega Transmitters of the Cold War, they were literally photons kilometers in size but very difficult to produce "individually". There is also a whole area of the spectrum where we find it very difficult to produce coherent radiation due to scale... the Terahertz Region... we are only getting to go there "very slowly" but it is happening.

Everything here indicates the machinery of photon production... because they are bosons they can be emitted multiply all in the one boson quantum state. We can produce them in a variety of polarizations and even different spins from the "off the shelf" variety. They can be "tailor made" in size and energy. That is why we can make antennas of various geometries that produce these "packets" at different scales of wavelength at different parts of the full EM Spectrum. What we have is an area of the spectrum in which we can tailor make these photons depending on the resonance of the system we construct. We could do the same if we could only tailor make the "real atoms" but since "atoms are atoms" and form indivisible packets we can't take a knife to them and whittle off the corners to re-tune these "antennas" to our own specifications. Thus the "atomic shells" and indeed the "sub-atomic shells" have "exact dimensions" and they represent the ability to emit and absorb at discrete frequencies. They also represent "resonant" aspects of the spacetime they exist in.

This leads to this earlier post...
How many photons?, Question on technique and method : Good Elf previously
QUOTE
Virtual photons

The electron and nucleon interact by the electromagnetic force, the carrier of this is the virtual photon as has different properties to ordinary photons. Take for example two electrons.  These repel each other due to the electromagnetic force, we say that there is a mediator or exchange particle which is transferred between them, the photon.  If one imagines two ice skaters facing each other and one throws a ball to the other person both skaters will move apart, just as two electrons would repel each other.

When delving inside the proton (or neutron) it is not the electron which actually 'probes' the nucleon but the photon.  An electron gives some of its energy (and so loses some of its momentum) to the photon.  The more momentum which is transferred to the photon, the more energy it has and so the shorter the wavelength of the photon. One can imagine that a longer wavelength photon will only 'see' the whole nucleon and so be elastically scattered, but for shorter wavelength photons it can 'see' the constituents of the nucleon, the quarks inside.  This is why physicists want to build larger and larger accelerators, so that they can see more and more of the structure of particles.
Virtual photons

Note... this is a highly authoritative description/link of virtual photons and indicate their true origin and in my opinion as to why people usually do not "get it" about quanta. I note zephir has not responded to this earlier post but it clear to me that energy is "granular" only when it is transferred between systems and tends to be continuous within systems in the inertial frame. This is a string property and it is the way strings propagate. As I have always said the quantum properties are not fundamental and this is shown in many present day experiments where you can actually vary the quantum properties of certain systems such as spin and "phase" and some properties such as relativistic mass are not "fermionic" but "bosonic" in nature (as stated by Einstein himself in his own way). There are also many other properties that fermions can have that degenerate into bosonic properties... this is easily demonstrated with BEC's (Bose-Einstein Condensates). This is the basis of my point of view. Also to the investigation of "Bright Matter Solitons" and to their stable or unstable nature. Clearly to create "quanta" this energy needs to assume configurations which link through time (resonance and reciprocal space) with space, this is an expression of CPT laws well known in particle physics.

This is why many authorities have totally mistaken this behaviors as "welling" up from the "Planck Length" as the origin of quantum behavior, this has no experimental support, it is simply a philosophical "gesture" of hope for those who want ultimate theories that are beyond testing. It is very clear to me that the origin of the quantum is in "sampling" of a continuous wave... that is it's truncation in time and space as every process actually is. This leads to Fourier Theory (add dimensions when needed) and that is the basis of quantum theory and the wave-particle duality since these represent the frequency domain and (impulse) time domain respectively.
Convolution Theorem: Figure 4.8 illustrates this result using cosine and rectangle functions in the time domain.
This shows when you take an "infinite" sine wave and truncate it in the time domain what the transform is in the frequency domain.
E = hf where E is the energy h is the impulse response of the "medium" and f is the frequency. If you use "natural" units you can readily identify the quantum packet as the produce of the two intrinsic properties of spacetime linked through the speed of light to "nip off these quanta".

This leads directly to the discrete frequencies in a wave packet and to the broadening of the internal spectrum leading to line broadening (as previously mentioned). This is directly in accordance with Heisenberg's Uncertainty Principle and leads naturally to concepts of a reciprocal space (Hilbert Space) for higher dimensional Universes such as our own. The maths is readily available for all to see if that is what they want already by many authors on the web.

Immediately proceeding from this is de Broglies Matter Waves evolving in the evanescent field of particles in that reciprocal space.
user posted image
At once can be seen the relationship at the low velocity end to the high velocity end of the Speed of Light and Einstein's Special Relativity. De Broglie and Einstein SR is actually the one and same theory only wrapped in higher dimensions (or reciprocal space). This is the "winding" of String Theory but as a reciprocal is an expression of the principal quantum number "N".

Now the fermion and the boson worlds in an atom are really one and the same at different scales. These were developed from the one theory of Quantum Electrodynamics ... the connection to Quantum Chromodynamics is the natural extension of QED to the sub-atomic realm. We call one "matter" the other "energy" but in reality they are not different but an expression of Ed Witten's 11 dimensional manifold. The connection is obviously "harmonic" not spatial.
User posted image
You are probably aware of the rest of this...

With the atom you can see this expressed this way...
Wolfram: Spherical Harmonic
Pretty pictures... These (with appropriate co-efficients) are the "orbitals". Notice I have chosen a pure classical theory not quantum theory ... yet the quantum numbers emerge spontaneously. Naturally with complex atoms this is far more sophisticated and cannot be solved accurately (hence perturbation theory). Not even for the electronic shells ... more importantly it is almost impossible to solve for the fermions in the nucleus. The problem becomes even more intractable as you shorten the scale even further (same problem... but different space... inside "matter"). A lot less data there and that is why they are building the LHC at Cern. Solutions at the Planck length are just a lot of nonsense and cannot be proven or disputed without any of the experimental data. Garbage in... garbage out theories where it is the realm of pure speculation... wrong minded speculation. There may be a solution but it will be impossible to determine that uniquely without experimantal data. In the meantime a top down theory lacking the essential dimensions and interpretation already exists.

Yet this is the solution already in existence and long standing. Its an "open secret".
A missed unification?, Unifying relativity and quantum physics

Cheers
Good Elf
Hi Bobbo, RealityCheck, Yquantum, Troc, Zephir et al

I realize that this theory links with the idea of a "Theory of Everything". Naturally a TOE is a pretty big theory since it MUST answer "everything". No individual human answer in a Forum thread such as this can possibly hope to answer every question possible in the Universe... therefore it is going to be very "brief" compared with its "breadth".

QUOTE (Bobbo Posted on Yesterday at 12:50 AM+)
Wow! The question seems to have stirred up an old conflict of ideas. I had thought the wave idea was long abandoned and the theories were more to the center of the photon as a particle.
There are those that want to bury the wave idea but it is the basis of almost all new developments. You will get nowhere today without an understanding of the wave properties of not only light but matter. This links such theory as "matter waves", particle entanglement with Photonics and Special Relativity. I have been at pains to emphasize the link between Special Relativity and de Broglie waves as representing two ends to the one issue of inertial frames and "delocalization" of the quantum. The concepts of the "hidden quantum" and what it represents as a wave and as a particle interaction is a very broad subject. I am just bringing together these very different disciplines into what I believe is a harmonious whole. Unfortunately you must take what I am saying as not being a standard theory and you will not necessarily find this anywhere else. I would also caution all that standard theory does not answer all the problems and is simply "papering over the cracks in the wall". A single Theory of Everything will need to have a single answer for "everything"... it may be complicated but it should be a single theory... not a lashing together of various operation models that do not work well together and are poor at predictions.
The resemblances in mathematical structures between the optical constants of artificial electromagnetic media and some physical phenomena in field theory : Jian Qi Shen
Please note the parallel between the equations on the top of page three... EM Theory and Schrodinger's Equation.... they are expressible as the same phenomena. They relate to different mathematical spaces though that do not correlate physically... one is the normal spaces of Einsteins Physics and the other is the probability spaces of quantum theory. Similar but not the same. One an exact relationship in EM waves and the other an expression of "probability" waves. One is physics the other is statistics.

Due to Heisenberg's Uncertainty relationship which is an indirect expression of be Broglie waves, the movements of particles in space is "delimited" by a world line that depends on the velocity of the particle. The higher the velocity of the particle the narrower the world line and the lower the velocity of the particle the less localized and broader the world line becomes. In the limit where the particle is "stationary" de Broglie theory states that it now occupies "all space" and is no longer a "line". This has been known for a very long time. De Broglie and Schrodinger knew it Einstein knew it and all objected to the point particle approach which leads to present problems. String Theory is attempting to redress the problem of the not point-like nature of "everything" and replace it with dimensions that depend on a distributed property. Thus a moving particle sweeps out a tube in space not a line. The faster it moves the smaller this spatial and temporal tube is. This tube has special properties at nearly the speed of light and undergoes a "rotation" of arcsin(V/C) in spacetime we usually refer to as "length contraction" around the wall of the light cone. All these points really refer to the space in which particles move and not the so called "particles" themselves which are delimited by their space. This is a form of quantum geometrodyunamics.

Cheers
jal
Hi Good Elf!
I like that last reference.
http://arxiv.org/PS_cache/physics/pdf/0405/0405007.pdf
QUOTE
....The significance of such comparisons lies in that: (i) the unification in mathematical descriptions shows that many physical phenomena
and effects, which seem to have no connections between them, actually share almost the same mathematical structures; (ii) it can provide clue to us on suggesting more new effects which is similar in mathematical descriptions to the familiar phenomena in other areas.

This paper demonstrates that there is much similarity between the mathematical structures of optical constants of artificial electromagnetic media (such as chiral media, left-handed media, photonic crystals and EIT media) and some
physical phenomena in field theory, including general relativity, quantum mechanics, energy band theory, etc.. The aim of this paper is to show that the unification in mathematical descriptions can clue us to the discovery of some
new physical effects, by analogy with those in other fields.


jal smile.gif
Good Elf
Hi Jal, Bobbo, RealityCheck, Yquantum, Troc, Zephir et al

QUOTE (jal Posted on Today at 1:08 AM+)
Hi Good Elf!
I like that last reference.
http://arxiv.org/PS_cache/physics/pdf/0405/0405007.pdf
QUOTE
....The significance of such comparisons lies in that: (i) the unification in mathematical descriptions shows that many physical phenomena
and effects, which seem to have no connections between them, actually share almost the same mathematical structures; (ii) it can provide clue to us on suggesting more new effects which is similar in mathematical descriptions to the familiar phenomena in other areas.

This paper demonstrates that there is much similarity between the mathematical structures of optical constants of artificial electromagnetic media (such as chiral media, left-handed media, photonic crystals and EIT media) and some physical phenomena in field theory, including general relativity, quantum mechanics, energy band theory, etc.. The aim of this paper is to show that the unification in  mathematical descriptions can clue us to the discovery of some new physical effects, by analogy with those in other fields.

"Long time no see" He he he... Yes this is one of the favorite papers of mine. Sorry I have been brushing up on my last post and have probably added something since you have first seen it. That addition is important for others to grasp (please read that last paragraph). Shen's paper and Williamson's Paper are "small picture" views of the required direction of any future String Theory and these points are where the theorists are "slipping up" and not pursuing the real goal (as outlined in this thread). I would be interested in your ideas though.

EIT and other phenomena are the QED end of String Theory. The theory is missing the important quality of phase. What I am referring to has a very strong basis in experimental physics not in any "philosophy" developed in isolation from the world of reality. In the end reality is far stranger than the fiction being dished up by some. Everything I have said is experimentally verifiable fact and is unrelated to any fantasy about the dimensions below the Planck Length far beyond any experimental science ... forever.

Cheers
jal
Good Elf
I like your presentations.... they are substantial and informative. smile.gif
QUOTE
The aim of this paper is to show that the unification in mathematical descriptions can clue us to the discovery of some
new physical effects, by analogy with those in other fields.

The waves, ... heheh ... are not going to go away. The fact that "physics" round things off by using a point and that they have to renormalize does not mean that it's wrong.
To me it means that we maybe hidding (unconsciously) "some new physical effects".
The above mentioned paper did not leave our 3d universe. I like that.
Come to my party with your insights.
You can surely bring a top down approach without going past the Planck scale.
You could be in charge of the game of "caps". biggrin.gif
jal
Good Elf
Hi Jal, Bobbo, RealityCheck, Yquantum, Troc, Zephir et al,

QUOTE (jal Posted on Today at 1:36 AM+)
The waves, ... heheh ... are not going to go away. The fact that "physics" round things off by using a point and that they have to renormalize does not mean that it's wrong.
Yes... not wrong... just out of its "depth"... literally. More physical dimensions and this leads to a harmonic "hyperspace" for "String Theory". Suddenly it is possible to understand how those 11 dimensions "fit" together.Our physics "fit" in groups of three with other "tangential hyperspaces nearby". They are reciprocal to our spaces when you try and view these from our "flatspace" of three dimensions. We have excellent physics that keep things in the box of our spacetime but "wrap" in harmonic dimensions. Relative to us these are compact dimensions and represent the particles and sub-atomic particles which embed other holographic "environments" through Kondo Phantoms which mimic our Universe down to the last details. This aspect is illustrated in a recent thread that I contributed to in response to StevenA...
Perpetual motion?, Cyclic photon reflections:StevenA
If you want to visit real other Universes and travel back in time then there is plenty scope for that there.
QUOTE (jal Posted on Today at 1:36 AM+)
To me it means that we maybe hiding (unconsciously) "some new physical effects".
The above mentioned paper did not leave our 3d universe. I like that.

He he he... Come into "my world" and leave all this "reality" behind. biggrin.gif wink.gif Hidden Quantum Phenomena are other dimensions flattened using three dimensional physics and "projection" through renormalization. Here is a lower dimensional equivalent of this "projection" ..
Wikipedia: Möbius transformation Look at the pretty pictures half way down... rolleyes.gif Quanta are "projections" on to our flatspace of the "Riemann sphere" in higher dimensions (locally these are 10 dimensional in reciprocal space). You can look back over my stuff to get a heap more on this. He he he! Quanta are "excitations" of this "spherical environment" projected into our flatspace. I can show you an applet that illustrates where all the quantum numbers come from. Do not be confused by the scale of anything.

I guess this will lose a lot of people but "no pain no gain". As Leonard Susskind once said "If anything is a string... everything is a string".

Cheers
jal
Good Elf
I always get good stuff from you in our conversations. smile.gif
We just interpret it differently.
Sorry for the interruption of the one photon.
jal
Good Elf
You are welcome Jal... take whatever you want (need) and leave the rest. rolleyes.gif It is my observation that "our" Physics "works" in three dimensions plus time ... no more ... no less. That is why "we" cling to this paradigm. Everything we do mathematically tries to fit this paradigm... Yet they cannot fit and are mutually inconsistent so we end up with all the problems and cannot achieve "unification".
Confused2
Good_Elf, RC, y, Z, Troc et al,

I hope this is still relevent..

Since 1967, the International System of Units has defined the second as 9,192,631,770 cycles of the radiation which corresponds to the transition between two energy levels of the ground state of the Caesium-133 atom.
Delta E = hf = 6.6260693(11) x 10^-34 /9,192,631,770 the (11) is the uncertainty in the last two digits
= 7.2080228 (13) x 10^-44 Joules

The wavelength is 3.2612 cm. .. pretty big really
And a rubidium atom is of the order of 0.248 x 10^-9 metres .. pretty small really.

So how can something so small produce something apparently so big? .. if not so big then how big?

Is the (relatively) huge wavelength of the photon related to the way photons are hatched in atoms? The way we detect photons? Or something completely different?

(I suggest something completely different)

-C2.
Good Elf
Hi Confused2, Jal, Bobbo, RealityCheck, Yquantum, Troc, Zephir et al

QUOTE (Confused2 Posted on Today at 12:29 PM+)
So how can something so small produce something apparently so big? .. if not so big then how big?

Is the (relatively) huge wavelength of the photon related to the way photons are hatched in atoms? The way we detect photons? Or something completely different?

(I suggest something completely different)
He he he... don't be so coy... don't "suggest it"... say what you really mean. Time for a good discussion.

I will start the ball rolling. Tell me when was the last time you "saw" a photon while in the quantum state? The answer to that is "never".
User posted image
The truth is we never actually "see" this picture but this is what the picture really is when we have a continuous radiator of many photons when being fed from a suitable source of continuous energy. This is not what is happening in a single atom and it is "synthetic". Atoms are not "built" to be continuous sources of radiation like dipole antennas, however the mechanism bears a fundamental similarity to the process in single atom and their shells but on a vastly different scale.... the optic frequency scale. "Atomic antennas" are not individually "fed" with continuous sources of radiation, it is usually a more haphazard affair and the energy "feed' is quantized and so is the energy output. I would repeat what I have quoted above about the "virtual photons".
QUOTE
Virtual photons

The electron and nucleon interact by the electromagnetic force, the carrier of this is the virtual photon as has different properties to ordinary photons. Take for example two electrons.  These repel each other due to the electromagnetic force, we say that there is a mediator or exchange particle which is transferred between them, the photon.  If one imagines two ice skaters facing each other and one throws a ball to the other person both skaters will move apart, just as two electrons would repel each other.

When delving inside the proton (or neutron) it is not the electron which actually 'probes' the nucleon but the photon.  An electron gives some of its energy (and so loses some of its momentum) to the photon.  The more momentum which is transferred to the photon, the more energy it has and so the shorter the wavelength of the photon. One can imagine that a longer wavelength photon will only 'see' the whole nucleon and so be elastically scattered, but for shorter wavelength photons it can 'see' the constituents of the nucleon, the quarks inside.  This is why physicists want to build larger and larger accelerators, so that they can see more and more of the structure of particles.
Virtual photons

I suspect this is the origin to "quantum back-action".

What we know of photons is they propagate as waves and interact as particles. They can also tunnel through barriers but that penetration is strictly limited to a certain distance dependent on their wavelength. If the barrier is too "formidable" it will interact as a particle. We also know that this wave phenomena is very "fragile", the qubit of information they carry can be easily lost if not "handled" correctly. This qubit is related to the way the waves interact over space and can instantaneously communicate over almost "infinite" distances through "entanglement". This is effectively 'along" the wavefront as a phase velocity which in that direction can be infinite in speed.

The delayed Quantum Eraser Experiment shows that time is not a problem to events and this can communicate an event backwards into our past relative to our time but is really only a single event relative to it's native "timeless photon state". We also know that they spread. Other particles do not spread appreciably. This spread is related to the geometry of the space they are spreading in. My view is (and it is an "opinion") that the difference between photons and other particles is primarily due to the "internal" space in which the photon is propagating. This is different from the same space as seen externally from other frames of reference. This spread is confined to the wavefront and not to the wavelength which remains totally fixed. This means they become flattened like pancakes as they travel. The energy density falls rapidly with distance from source. It is very plausible and can be illustrated that de Broglie waves are emanating (or tunneling) from an evanescent zone of "particles" that contain "circulating" photons which are still traveling at the speed of light only "on the spot". We also know that particles can not only be created from photons, their annihilation also releases them as well. There are certain rules that need to be observed to perform this trick and they relate to particle properties and conservation of CPT.

They have integer spin. They have helicity. They obey an inverse square law. They diffract and produce interference fringes. We also know that the photons can "inhabit" a single state when they propagate as a "coherent boson wave". Though they interfere with each other they are non-destructive in their action and they can propagate over light years without any disruption to phase or to the energy of the "packets".

Over to you C2! wink.gif

Cheers

Good Elf
Hi C2,

Your calculation appears to be correct. The wavelength of a photon should relate to the frequency of the oscillation, that is the time it takes for a transition. Of course this is then truncated before and after a transition. But this is a microwave photon. The splitting is not due to an electron transition emitting a photon but due to the magnetic dipole moment perturbation of the atom as a whole which is a different beast ... its size is unknown to me (it suggests a kind of low frequency solenoidal field a secondary spin) but resonance suggests that it must be "bigger" in size because it is much lower in energy. It is a magnetic interaction between the nucleus and the electrons magnetic moments. It effect extends physically further from the atom than the conventional shells of the electrons but are very much lower in energy. Shell Transition photons are far shorter in wavelength and relate to the size of an atom. This is the reciprocal nature of of the radiator. The important point is this radiation is not "continuous" but is ancillary to the transition at the ground state. It only happens when you have that base transition you see this equivalent extra microwave photon emitted. This is during the act of the emission of the primary photon "transitioning" near the ground state of the atom. It seems this may be a secondary "kick" to the system due to conservation laws of momentum and energy of the atom as a whole, perhaps due to retarded fields interacting. Are you trying to say that the photons are emitted in pairs or that sequential photons can emit or absorb this microwave photon to shift the ground state line marginally? Anyway.. this frequency must be read from a instrument and counted to mark seconds. Exactly how this is measured in a Lab is a bit of a mystery to me. Interested in what you have to say about this.

Cheers
Confused2
Your second post first .. I repeat..(sorry)

Since 1967, the International System of Units has defined the second as 9,192,631,770 cycles of the radiation which corresponds to the transition between two energy levels of the ground state of the Caesium-133 atom.

Doesn't just correspond .. it IS.. can't get closer to coming from an atom than that.

1st post..

QUOTE (Good_Elf+)

I will start the ball rolling. Tell me when was the last time you "saw" a photon while in the quantum state? The answer to that is "never".


We are both equally damned by this!

QUOTE

"The electron and nucleon interact by the electromagnetic force, the carrier of this is the virtual photon as has different properties to ordinary photons."


I feel this is too self-referential to be helpful.
I can't do much better than fall into the trap of my own making..
The only property transferred by virtual photons seems to be momentum, in fact the only property transferred by any photon is momentum .. it seems too simple to be true.. but I think it is.

Assuming I'm right (????)..

If all we have is momentum then it is no longer sufficient to claim that an electromagnetic wave works because of electromagnetism.

The 'electromagnetic wave' becomes no more than a mathematical construction to explain the transfer of momentum. You may have noticed on other threads I'm having a bit of a problem understanding Maxwell's equations and the EM wave equation which require 'time' when (at 'c') there appears to be no 'time' for the equations to have any physical meaning in. The Poynting vector and E x H seem to be all that remains with any meaning.

( http://en.wikipedia.org/wiki/Poynting_vector )

QUOTE (->
QUOTE

"The electron and nucleon interact by the electromagnetic force, the carrier of this is the virtual photon as has different properties to ordinary photons."


I feel this is too self-referential to be helpful.
I can't do much better than fall into the trap of my own making..
The only property transferred by virtual photons seems to be momentum, in fact the only property transferred by any photon is momentum .. it seems too simple to be true.. but I think it is.

Assuming I'm right (????)..

If all we have is momentum then it is no longer sufficient to claim that an electromagnetic wave works because of electromagnetism.

The 'electromagnetic wave' becomes no more than a mathematical construction to explain the transfer of momentum. You may have noticed on other threads I'm having a bit of a problem understanding Maxwell's equations and the EM wave equation which require 'time' when (at 'c') there appears to be no 'time' for the equations to have any physical meaning in. The Poynting vector and E x H seem to be all that remains with any meaning.

( http://en.wikipedia.org/wiki/Poynting_vector )


Since the electric and magnetic fields of an electromagnetic wave oscillate, the magnitude of the Poynting vector also oscillates


We can send a continuous (non-coherent) blast of radiation and the Poynting vector will not oscillate .. except for thermal (and quantum) noise. Could it be that the clues you are picking up about what is happening when we can't see the photon are coming from coherent radiation .. when the number of photons is varying... there's only one sort of photon .. what varies about it during the course of a coherent radiation cycle? The number of photons or something else?

Takes us back to Ivor Catt.. nobody liked him either. Sniff.

All comments welcome.

-C2.
Confused2
Sorry GE,

I wasn't quite ready for your second post in my last post.. somewhat off the off-topic!

The reference I used was http://en.wikipedia.org/wiki/Atomic_clock#How_they_work

My strong impression is that there are no extra photons involved .. as you suggest..
".. sequential photons can emit or absorb this microwave photon to shift the ground state line marginally.."

Interestingly the life (I assume half-life?) of the excited state is in the region of 10 minutes ( http://en.wikipedia.org/wiki/Hyperfine_transition ) hence (I guess) the length of time such a clock takes to settle down to some sort of equilibrium. My expectation would be that the life of a state would increase as the energy step decreases.

Aargh..
I've just noticed something in the spacetime interval.. s^2 = r^2 - c^t^2 .. obvious really .. s^2 = 0 at 'c' but r and t still have real values. Potentially Maxwell's equations can still work perfectly (I've not looked at this yet).
It doesn't really affect the question of whether or not there is anything other than momentum involved here.

Also the time dependent qualities of a photon... my own feeling is that the time you are most likely to detect one is x/c after it was emitted .. with a bit of error either way this gives both wavelength and thence frequency.. with neither property having any real meaning for a single photon.. the only real property being momentum.

A fully functioning wave equation looks well equipped to probe curved space .. could this be why it works? The only reason it works?

-C2.
Good Elf
Hi Confused2, Jal, Bobbo, RealityCheck, Yquantum, Troc, Zephir et al


QUOTE
Interestingly the life (I assume half-life?) of the excited state is in the region of 10 minutes ( http://en.wikipedia.org/wiki/Hyperfine_transition ) hence (I guess) the length of time such a clock takes to settle down to some sort of equilibrium. My expectation would be that the life of a state would increase as the energy step decreases.
I see no contradiction in that. The "virtual photon" is "emitted" only during the transition phase (if at all... probably not) which is a lot shorter than the half life. I would "imagine" that if the photon is not able to be "emitted", the Poynting energy will flow to the nearest available currently executing electromagnetic process as a "potential energy excess".

I also see that as the energy gap decreases there will be a point at which the "photon" cannot be individually emitted or absorbed by any single atom. They become "inductive processes" rather than "radiative or transmissive" ones. This causes a flow in the Poynting Vector rather than emission of the photon which is related to the minimum geometrical system to efficiently emit that photon. To efficiently emit this photon it would need to physically be about 3 cm in size. It is a case of matching the "Load to the Line" or in this case a cavity excitation in one mode feeding another mode and modifying it slightly. In my "minds eye" I see that this energy slightly modifies the shape of the "cavity" and slightly changes the tune of the ground state emission line cavity, while presenting with the additional energy to "fuel" it. A kind of "elastic" deformation of the cavity space by energy. Since it is not "material" (e.g. metal box or waveguide) you will need to read between the lines as to what this "dynamic elastic medium" really is or is defined by and explain it to yourself in terms of your own philosophy. A similar mechanism to quantum back action as I stated previously. You also need to have a "little thinky" about what guides the Poynting Vector in this domain. Of course it is quantum statistical... eh? ohmy.gif It's "Anything can Happen Day"... throw a dice. blink.gif wink.gif Nothing to see here... Move along!

All these "ideas" give me a way of dealing with "virtual photons" in a more physical way rather than trying to analyze the maths. It is my contention that since we do not have the level of data to measure this virtual small scale process, a mathematical model may not provide any real insights. Although I can think of a couple of analyses I have referenced before supporting this idea "in theory". They would deal with advanced and retarded electromagnetic potentials in the near field.

Cheers
Confused2
Hi Good_Elf et al,

I hope this deviation is OK .. ( please complain if not)

Best atomic clock I can find
http://www.ptb.de/en/publikationen/download/zeit_e.pdf (see "The Basic Principle Behind Atomic Clocks ")

Not what I expected! I see little alternative to the conclusion that the A state atoms are being flipped to B state (or a 50-50 mix of A/B states) by direct absorption of microwave photons. It doesn't look like the lifetime of the state (interesting though) has much to do with it because there's active 'flipping'.

My references to the Poynting vector .. hmm.. Maybe see what you make of the atomic clock and take it from there.

-C2.
Good Elf
Hi Confused2,

Thanks for the details on the clock. Obviously I was talking about the sub-atomic scale processes which "pump the energy" into the state via "virtual photons" inside the near field. The clock is a highly refined device and I have a reference to a version of an original clock here below. This makes some sense to me where the Naval Observatory is far too "obscure" and "jargonized" to be as illuminating about their Fountain Clock.

While the atoms are in this excited state (for the 10 minutes) they behave slightly differently in a magnetic field to the ground state. The differences is in the total spin of the atom being affected slightly and the components of the atom... the electrons and the protons have a combined magnetic dipole moment. The brochure you posted is a little abstract in the details. I will just try to clarify this point as I see it... the lower energy state atoms are selected from the excited state atoms (as emitted from the Cesium Oven)... only the lower energy state atoms enter the long chamber, selected "magnetically" using a gradient magnetic field. The internal cavity is saturated with radiation initially at "nearly" the appropriate excitation energy of 3.26CM. Some of these lower state atoms are promoted by absorbing this cavity energy and transition to the "higher state" depending on the quality of the tune of this exciting "continuous" radiation. The atoms exiting the chamber are once again selected in a similar way as before for their excitation levels magnetically. This time only the excited state atoms are selected and counted by using hot wire ionization and passing into a Mass Spectrometer (probably to select the right isotope of Cesium and to discriminate against any possible other impurities).

The final count is done by an electron multiplier counter at the far end of the Mass Spectrometer through a hole or slot at the appropriate deflection position. The way it works is this atomic count rate reaches a maximum when the cavity is excited with this high tune oscillator at the exact resonant frequency that "splits the line". An electronic feedback circuit "pulls" this oscillator optimizing this resonance peaking (maximizing the number of excited atoms in the beam being counted). The absolute number of atoms is not important but the relative numbers per second indicate if the excitation frequency is "on tune". This secondary frequency of presumably 9,192,631,770 hertz, in the "external circuit", is then counted down electronically to a one second interval.
Cesium Atoms at Work
This has a better description but your brochure has a better illustration.

Cheers
Confused2
Good_Elf et al,

Thanks for your last post .. we seem to be pretty much in agreement about the mechanism of the clock.

QUOTE (http://tycho.usno.navy.mil/cesium.html +)

The frequency involved is that of the energy absorbed from the incident photons when they excite the outermost electron in a cesium atom to jump ("transition") from a lower to a higher orbit.


There (later) seems to be a bit of a fluffing going on regarding hyperfine transitions as opposed to 'straight' electron excitation which you might feel invalidates the (my) intended result which is (was) to show that the size of the photon need not be related to the size of the atom. Hopefully we agree that the excited atoms leaving the cell would 'ping' out a microwave photon after ten minutes or so. The hyperfine transition seems to be due to spin which (I think) we know is either up or down .. there doesn't seem to be a mechanism for spin to change very slooooowly .. so (to me) it looks like the photon is an amount of energy (actually momentum) rather than a 'size'. I know you're going to hate that sad.gif .. are you going to force me to produce more evidence ph34r.gif ?

-C2.
Good Elf
Hi C2,

QUOTE (Confused2 Posted on Yesterday at 4:07 PM+)
The hyperfine transition seems to be due to spin which (I think) we know is either up or down .. there doesn't seem to be a mechanism for spin to change very slooooowly .. so (to me) it looks like the photon is an amount of energy (actually momentum) rather than a 'size'.
Actually it is up down and a superposition of both states... a zeroth state (qubit). You forgot "Orbital Angular Momentum" which is also spin that individual photons and all other particles can have. It is well known that light can carry spin quanta (as you say). This is equated with "photon spin angular momentum" and there is another... "Photon Orbital Angular Momentum". These are also quite distinct from linear momentum that can also be carried by a photon...
Momentum = h/wavelength (de Broglie)
These two spins are not restricted to the "atom" but do obey quantum laws and take on quantum numbers and are exhibited by coherent radiation and obey the same laws of "weak sources" used to verify non-locality of the photon (e.g. Young's Interference Experiment). The more interesting property is also carried by a single photon too. The phenomenon is called Pancharatnam Phase. It is a phenomenon closely allied to Berry Phase. This endows the photons with "Orbital Angular Momentum " on a Riemann Sphere. This "spin" can be modified. Photon spin can be modified "very slooooowly" in the "evanescent region" as combinations of spin angular momentum (which has values of +1, -1 or the superposition of 0) and Orbital Angular Momentum which can have integer values of 0 or up to + or - infinity (same units as ordinary spin and they can be 'added" or "subtracted". Quote... "It is important to note that in both cases we can vary the phase by changing either the shape of the path of the light or the state of polarization without changing the optical length of the path. Changing the optical path length introduces dynamical phases. This aspect makes geometric phase boundless. That is, we can keep increasing it without limit." (my emphases) This is equivalent to "Orbital Angular Momentum" spinning it up or spinning it down. These two types of spin can add or subtract as these spins are really the same except that one spins at a center and the other spins about another center (of a beam). This is because a single photon can have both these spins at the same time, the angular orbital momentum can be a group property that is "bosonic" and is shared by each individual photon (one at a time as shown in some excellent work on angular orbital momentum quantum entanglement of individual photons by Zellinger)... or not. It has been shown that a single photon can be encoded with an infinite amount of information... theoretically unlimited... and is the superposition of an infinite number of dimensional states co-habiting each and every individual photon and not just that one qubit that can be encoded using simple spin alone. In theory you could put the entire Bible on to one single coded photon and have plenty of "room to spare" for all the other books mankind has written as well. Of course this level of technology awaits the future and at present several states are all that can be handled at present..

The use of this spin can be quite useful as a "tractor beam" that can grasp an object in three dimensional space and hold it there, manipulate and even rotate it in space to inspect it or put it elsewhere. Practical devices called "optical tweezers " have been built already for exceedingly small particles for example the manipulation of individual DNA strands.
http://www.aip.org/pnu/2003/split/639-2.html
http://physicsweb.org/articles/news/6/6/8
http://ej.iop.org/links/rvtYRQ1ls/ICHi9SJG.../njp4_1_103.pdf
http://xxx.lanl.gov/abs/quant-ph/0104070
http://www.quantum.univie.ac.at/research/p.../ali/index.html
http://departments.colgate.edu/physics/fac...cles/spie06.pdf

PS: There is an interesting tie in with Williamson's Paper as well since this "highly spun up" photon if forced to travel a Geometric (Berry) Phase path in an evanescent region will lead to electric charge as well, depending on topology as you may expect. As you see this leads to a force at a distance due to non-locality of photons. They are quite interesting don't you think? wink.gif

Cheers
Confused2
Hi Good_Elf et al (if any left!),

Bit of a 'time out' post here.

An attempt to define the 'rules' a bit.. whereas QM speaks of momentum we find classical EM theory speaks of E and H fields .. clearly there is a strong relationship between quantum momentum (including angular) and the E and H fields of classical EM. I am sure we agree we are using metaphors (sometimes just 'words') to mean what we what we want these words to mean. We can mix metaphors/'words' to get results with varying degrees of 'information content' and varying degrees of accuracy in the face of strict analysis. IMHO examples of mixed metaphors include the de Broglie hypothesis and the Williamson electron paper... which (hopefully) explains my objections to both.

In my chosen example of the hyperfine transition I was restricting myself to spin .. as far as I know this has only two states. Since spin is the source of the hyperfine splitting (agreed?) it seems we need this spin inversion process to proceed sloooowly to make our 9GHz photons (depending on your definition of sloooowly of course). The figure of 7.2.. E-44 Joules for the photon energy ought to take into account all the spin states of the photon otherwise we'd potentially be able to get more out than we put in by choosing the appropriate orientation of a detector. My 'point' depends entirely on the length of time it takes to an electron/nucleus spin situation to flip. We could look at hydrogen hyperfine line (21Ghz from memory) and say 'Aha .. lighter nuclei flip faster' .. which would kind of shoot me down a bit. Perhaps we should look to other hyperfine transitions for a pattern .. if you wish.

We both accept that the quantum properties we assign to photons/electrons etc MUST give the experimental classical results when applied to many photons/electrons BUT the process doesn't necessarily work in reverse. If we turn (say) a paperweight over .. we observe it as a continuous process .. at a quantum level (I suggest) it is really flipping between states and the macroscopic 'continuous process' is the illusion.

My particular interest here is in the production of a single photon as a result of a 'transition' within an atom.. I hope this is a shared interest.

Best wishes,

C2.
Good Elf
Hi Confused2,

I am aware of your understanding of spin... hyperfine splitting utilizes the Orbital Angular Momentum and is an interaction between various components. It is not just a simple spin up or spin down photon. Anyway we are speaking about the evanescent zone where we have "virtual photons". You would notice the difference between an emitted quantum and a process that never emits. It is my contention that a photon that does not emit simply redistributes the energy to other processes. In this case create additional modes for the primary photon. I think you understand that the transition you are speaking about ... hyperfine splitting does not actually emit a microwave photon. What happens is it "splits" the primary line which is still very close to the unsplit line.

As to OAM I am unsure if you are getting the picture there. What I have written is "standard theory" and I am not playing with words. Any emitted photon will be quantized but evanescent processes are simply not quantized until they occur.

QUOTE
Virtual photons

The electron and nucleon interact by the electromagnetic force, the carrier of this is the virtual photon as has different properties to ordinary photons. Take for example two electrons.  These repel each other due to the electromagnetic force, we say that there is a mediator or exchange particle which is transferred between them, the photon.  If one imagines two ice skaters facing each other and one throws a ball to the other person both skaters will move apart, just as two electrons would repel each other.

When delving inside the proton (or neutron) it is not the electron which actually 'probes' the nucleon but the photon.  An electron gives some of its energy (and so loses some of its momentum) to the photon.  The more momentum which is transferred to the photon, the more energy it has and so the shorter the wavelength of the photon. One can imagine that a longer wavelength photon will only 'see' the whole nucleon and so be elastically scattered, but for shorter wavelength photons it can 'see' the constituents of the nucleon, the quarks inside.  This is why physicists want to build larger and larger accelerators, so that they can see more and more of the structure of particles.
Virtual Photons

This process pushes and pulls the energy of the emitted process which will be entirely quantized. The E and H fields are within that evanescent region.
QUOTE (->
QUOTE
Virtual photons

The electron and nucleon interact by the electromagnetic force, the carrier of this is the virtual photon as has different properties to ordinary photons. Take for example two electrons.  These repel each other due to the electromagnetic force, we say that there is a mediator or exchange particle which is transferred between them, the photon.  If one imagines two ice skaters facing each other and one throws a ball to the other person both skaters will move apart, just as two electrons would repel each other.

When delving inside the proton (or neutron) it is not the electron which actually 'probes' the nucleon but the photon.  An electron gives some of its energy (and so loses some of its momentum) to the photon.  The more momentum which is transferred to the photon, the more energy it has and so the shorter the wavelength of the photon. One can imagine that a longer wavelength photon will only 'see' the whole nucleon and so be elastically scattered, but for shorter wavelength photons it can 'see' the constituents of the nucleon, the quarks inside.  This is why physicists want to build larger and larger accelerators, so that they can see more and more of the structure of particles.
Virtual Photons

This process pushes and pulls the energy of the emitted process which will be entirely quantized. The E and H fields are within that evanescent region.
IMHO examples of mixed metaphors include the de Broglie hypothesis and the Williamson electron paper... which (hopefully) explains my objections to both.
I would not "mix" those concepts but you would have found an expression of Orbital Angular Momentum in the references I included and how this has been experimentally shown to obey an angular version of the Heisenberg Uncertainty Principle, only related to photons with OAM. In my last post I do not think I did mix them but I did refer to electrostatic fields arising in the evanescent region of spun light. This is a form of Orbital Angular Momentum that is able to be carried by single photons and literally "adds" to the standard angular momentum of a photon. This total spin has an infinite possible number of spin states and this is an experimental and theoretical fact.

An analysis of modern concepts and photon propagation is incomplete without this recently discovered phenomenon.

Cheers
Confused2
Good_Elf,

QUOTE (Good_Elf+)

I think you understand that the transition you are speaking about ... hyperfine splitting does not actually emit a microwave photon. What happens is it "splits" the primary line which is still very close to the unsplit line.


I'm assuming there is a spin transition of energy (say) S
Then I assume there is a (say) an A->B transition and an A->B+S transition in (probably) the optical region .. corresponding to electron excitation with/without spin 'flip'.
Here it seems we are exploiting only the spin transition which certainly absorbs microwaves .. otherwise the device would not work. It is my assumption that the absorbed (microwave) photon will come out as a microwave photon , the state having a life (half life?) of 10 minutes .. as noted earlier.
The http://tycho.usno.navy.mil/cesium.html reference speaks of ionising the cesium atoms after they leave the chamber.. (suggesting they are not already ionised) .. this would prevent any observation of the S photon but does not affect the principle.
I think we can see that classically (by virtue of size) a single atom could only 'appreciate' about a 10^-8 part of the E or H field of a classical EM wave .. insufficient to cause the S 'flip' which (imho) requires exactly S for the flip to occur.The classical expectation is that the energy of a wave is distributed in time and space .. the quantum expectation is that interactions occur(or do not occur) at a point .. in this case the 'point' is experimentally shown to be less then 10-9 metres .. or do you disagree?

QUOTE (Good_Elf+)

The E and H fields are within that evanescent region.

This is the classical metaphor .. which I am suggesting 'gets it wrong' by a considerable factor (>10^8) .. which is (of course) why I have chosen this particular example.
-C2.
Confused2
Hi Good_Elf,

I should have said earlier, your link..
http://ej.iop.org/links/rvtYRQ1ls/ICHi9SJG.../njp4_1_103.pdf
seems broken... hence no comments about it and I don't know how relevent it would be sad.gif .

Meanwhile..
Should we move to electricity/bubbles thread?

C2.


Good Elf
Hi Confused2,

Uggh.. sorry... Firstly this is the "original link" to that missing reference...
Uncertainty principle for angular position and angular momentum Sonja Franke-Arnold et al 2004 New J. Phys. 6 103 doi:10.1088/1367-2630/6/1/103. Sorry about that... a forwarded link created on the fly.

My understanding of the process is in the "original" Cesium Clock that I referenced, the ionized gas is passed through a "Stern-Gerlach" Type gradient magnetic field to "sort" the spin up from the spin down atoms naturally coming from the oven.
Wikipedia: Stern–Gerlach experiment
After selecting the lower energy state atoms (lets say spin down) and disposing of the rest, then passing through the chamber (long "saturation" exposure time) some of the former lower energy selected states have been "promoted" to the higher energy state (say spin up), the rest are "discarded" (all the remaining spin down atoms). These selected "promoted atoms" are counted (with some difficulty) and the numeric flux is a measure of Microwave cavity tuning in the system. A feedback mechanism maximizes the tune and the tuned frequency is what is down counted with a digital gate to give seconds.

My assumption in the case of the 'Fountain Clock", despite the "jargon" in Military Circles about "interrogations" and such, all these more sophisticated clocks are doing is allowing the atoms to be "saturated in the "radiant field" for longer periods of time and at a much lower thermal temperature ... near absolute zero (rather than furnace temperature)... allowing for a corresponding increase in the time the atoms are able to absorb the energy into the atom's evanescent field. This is fine since once they pick up the energy they retain it for around a half life of 10 minutes which is significantly longer than this "fountain time".

My "interpretation" is this energy is absorbed over time in the near field (think of Poynting "currents" parallel transporting the internal particle using the "virtual photon" around a "loop"). This is due to the effects of bosonic processes "pulling" on the energy of the lower energy line with the single "coherent" radiant field. This is similar to laser action since the cavity is excited with that single "radio" frequency. When the right amount of energy is absorbed (over time) the spin quantum state instantly "flips" through EM coupling and then it can technically "emit/absorb the new line", though this is not necessary since only the spin state is what is observed and measured as this is the ground state that is perturbed. If the RF cavity is "optically dark" then there is no reason for this optical line transition to actually occur. Luckily for the clock this promoted spin line "state" will also have a 1/2 life of a similar length to the primary spin line "state". So what we are detecting is a change in spin state not the actual emission of the line as an optical photon. Maybe a little more convoluted compared to a simple explanation but I am looking at a "wider context". What I am trying to say here is we have continuous internal evanescent processes changing energy levels internally but in the act of emission/absorption of a line a quantization process occurs.

Cheers
Confused2
Hi Good_Elf,

I'm drawing attention to this because it might clarify a point on another thread (missed opportunity for unification)

From:- http://www.iop.org/EJ/article/1367-2630/6/...njp4_1_103.html

Clearly, experimental results were obtained in the present study from light beams comprising many photons in the same orbital angular momentum state and, hence, are strictly applicable to classical beams only. However, the experiment is fundamentally one in which the measured intensity values arise through interference effects in linear optics. In agreement with other such interference experiments, we can infer that the intensity distribution measured for the many-photon result is proportional to the probability that would be measured if the experiment was repeated with single photons. Consequently, the angular uncertainty relationship between optical orbital angular momentum and the angular aperture applies both in the quantum and classical regimes. This is as anticipated, since the theoretical description relies on linear optics and, thus, is identical for single photons and classical beams.

My emphasis. My point.. the accepted view is that 'intensity' in the many photon EM metaphor is 'probability' in the single photon QM metaphor.

-C2.
Zephir
QUOTE (Confused2+Sep 20 2006, 11:46 PM)
My point.. the accepted view is that 'intensity' in the many photon EM metaphor is 'probability' in the single photon QM metaphor...

By AWT the probability function is the simply the mass/energy density profile of Aether - no less, no more.

User posted image

The AWT doesn't use the probabilistic concept at all. The God really does not play dice, it plays with wave pockets, confined by its own energy density.
To understand this requires the only thing: to consider the refused massive environment concept. Which is unacceptable by most of mainstream physicists.
Which isn't my problem... wink.gif
Confused2
Quantum mechanics makes a prediction about the probability of (say) a photon
being detected.

user posted image


The plate above shows photons being detected .. beyond (my) reasonable doubt the greater number of photons will be detected where quantum mechanics predicts the probability of detection is greatest. We have experiment matches prediction .. where does Aether density come into it? Does it give the same answer? If it does then it predicts the probability of detection. What else?

-C2.



Zephir
QUOTE (Confused2+Sep 21 2006, 01:48 AM)
We have experiment matches prediction .. where does Aether density come into it? Does it give the same answer? If it does then it predicts the probability of detection. What else?

You can consider the explanation here.
Pupamancur
QUOTE (Zephir+Sep 21 2006, 01:27 AM)
You can consider the explanation here.

Not good enough, because AWT is invalid. See here:

http://forum.physorg.com/index.php?showtopic=9309
PhysOrg scientific forums are totally dedicated to science, physics, and technology. Besides topical forums such as nanotechnology, quantum physics, silicon and III-V technology, applied physics, materials, space and others, you can also join our news and publications discussions. We also provide an off-topic forum category. If you need specific help on a scientific problem or have a question related to physics or technology, visit the PhysOrg Forums. Here you’ll find experts from various fields online every day.
To quit out of "lo-fi" mode and return to the regular forums, please click here.