Problem with the two slit experiment, Observing later

Hi Confused2, younghand et al,

He he he... typos... Yquantum is always warning about them. It does not matter who you are you will always make them. I have made quite a few myself. I have noted that when I have made them and I am unable to correct it (after an hour) it is easy to see that people who read these posts must either be very few or are not thinking too closely about it all from the number of responses I am getting. Alternatively they get the "drift" and realize it is a typo. Yes you are right with the above. Note though this is a transcript of a talk given by Aspect and not one of his "peer reviewed" papers. That is the benefit to having interested "well wishing peers". elves do not have such things so you must "beware"... He he he.

Orthogonal polarizers at any angle of setting will have a 50/50 (P=1/2) chance of passing an arbitrarily polarized photon. However there is a 1:1 correlation between orthogonal polarizers passing "entangled" photons and zero correlation when they are parallel. That is just what "entanglement" actually means.
Wikipedia: Photon entanglement
Clearly "screw" related to each other... exactly. To clearly illustrate how this relates to other properties of a particle such as an electron (fermion) consider the Stern-Gerlach Experiment as indicated in the footnote.
Wikipedia: Stern–Gerlach experiment
I call your attention particularly to the section "Sequential experiments". While not photon entanglement these spin states can be entangled too. You can see that electron spin polarization occurs in all three orthogonal planes "simultaneously". Remember that objects in three dimensions plus time can only spin in one plane (e.g. a Top) but in six dimensions any object can spin in three "fixed" orthogonal planes all at once (I stress fixed), add in the three degrees of freedom we seem to be living in and you have 9 linear dimensions plus time... "String Theory" and ten dimensions in all. Add an extra dimension (or more) if you want to allow "String Transport" and that makes 11 dimensions. My only "beef" with this view is the connection between each group of three spatial dimensions.

Yes.. I have mentioned it when I was referring to the Delayed Choice Quantum Eraser in this thread..

The photons "must" know just where they end up if viewed "outside of time" (C2 and StevenA will remember this point from an earlier posts elsewhere). In a dynamic Universe this is quite an interesting revelation. Such determinism is only possible if you "admit" to "Non-Local Supplementary Parameters Theories" (Translation: Non-Local Hidden Variable Theories)... One of which is Bohmian Mechanics that Aspect himself finds "attractive"... The EPR-Bohm Experiment. The big problem with Quantum Mechanics and its interpretation is the assumption of "locality". All 4D Theories of the Universe require "locality". QM is a 4D theory... Locality is "violated". Bohmian Mechanics is not a 4D Theory... it contains "at least" extra hidden parameters. String Theorists will maintain that these extra parameters are "linear dimensions" interpreted using a "configuration space". There are other interpretations one of which is Loop Quantum Gravity where these "dimensions" may only be parametric and added into spacetime to further characterize it but not physical "dimensions" (Zephir holds this view). Heim's Theory is a variant on this schema. Lee Smolin is pushing for the LQG view. I find this unacceptable since they are all simply "models". You just add in parameters to remove any perceived discrepancies.

Bohmian Mechanics "adapts" to providing an intermediate space that will have some "real" physical interpretation (a quantum "place" where particles actually go when unobserved, not actually part of our "spacetime"). Quantum Mechanics provides nothing in this "gap" and is found "wanting" in being unable to answer some very tricky questions as I have already stated in this thread... this is not my opinion it is a long standing problem with the theory and those who disagree point to the wonderful successes with local interpretations of QM and ignore the "measurement problem". Those who say this usually point to chaos and anarchy if a non-local view is accepted even though a number of experiments do point to it. I totally disagree.

Now I will continue on with a story here...

I am having the same problem, you are asking too many questions for me to cover all bases. I "wave my arms" sometimes because we have discussed all this before elsewhere.

I hope there are no unwarranted "assumptions". If you can could you point out the assumptions for me since I am trying to assume nothing "extra" but attempting to do away with quantum postulates.

But we lack an explanation for 2/ .

This is all tied to just how large the fundamental photon can really be considered and exactly where you may find this "particle" in "configuration space". While its wavelength in the direction of propagation is fixed by the speed of light, in the transverse direction it spreads quite dramatically. This is the same for one photon or many. The same spreading for all photons so that the further they travel from the source the the more of the Universe each photon explores. Remember this is a non-local theory and the photon is traveling in quantum space "undetected". The geometry is non-local so when we "detect" the photon it is "projected" onto the state vector. Do not assume for even a second that the projected state vector is the entire story... It is stripped of some dimensions.

Sorry , I don't understand this answer. My 'superposition' would assume the use of the correct statistics but I feel the wave can be fully analyzed as 'photons' (which would give us a probability distribution in time and space) .. your answer remains unclear.

Any probability distribution would be "secondary" to the dynamics of the particle in "configuration space". In configuration space the particles assume a normal three dimensional dynamics as they have "here" in our "spacetime"... The projection by "detection" removes the non-local aspect of the particles and "localizes then" through quantum demolition. When in configuration space the only indication of the particles is "indirect" through their waves and the way they interact with our local environment. Naturally we are unable to "see" this interaction unless we sacrifice a few of these photons to see where those waves are "pushing" those "eyes of the storm" around relative to the projection. The photon is more than just a point particle or even a little extended billiard ball, the "waves" fill the space and "penetrate" into ours in the evanescent region as de Broglie phenomena.

We know that photons cannot "lag behind" on a wavefront or "zip ahead" so they are confined to the expanding wavefront. They can criss-cross and self-interfere given the chance... that is within the one "expanding" photon you understand. Interference with other "fermions" can also occur too and "defines" the dimensional space in which they are moving. What one photon does in a coherent beam is what all photons in that beam do as "interference". I have stated before that there is a self organizing influence, even between "adjacent" photons emitted from a condensed source, to become partially coherent. This is just the way these bosons behave. Pairs of electrons also exhibit such synchronization of phase (Cooper Pairs... bosons). Not that this has anything directly to do with entanglement, but entangled photons also partake in boson states.

Cheers

Hi Good Elf, younghand et al,

Just a quickie..

yquantum posted this link on another thread .. just in case anyone missed it ..
http://www.fortunecity.com/emachines/e11/86/qphil.html

-C2.

Hi Confused2, younghand, Yquantum et al,

The key point in the experiment DCQE is this statement...

So the tree falls in the forest and nobody is there to see it... yet it falls (as it should). This flies in the face of certain Quantum Non-Deterministic Theories such as the Copenhagen Interpretation where the tree does not fall if it not observed, it remains in a "superposition of states". The page is a little "old" dated Jan 2002. I liked the bit about Bell when he commented just before his death...

These experiments only tested one possible avenue of this theory. It is crucial to realize that Bohmian Mechanics is not a Theory of Everything, it is an extension of current theory with "hidden parameters" so it is not even "String Theory". I fully accept the premiss that the particles go somewhere different to our spacetime between observations but it has to be clear that when you are performing experiments that you are actually testing true quantum states and not some sort of "pseudo-quantum state" that may not provide the desired result. Anyway this view by John Bell is in coincidence with Alain Aspect's point of view... Bohmian Mechanics is the "path" toward a partial understanding of the full picture. The idea that you have a guiding "pilot wave" which moves the particle in a certain way is really only a hidden variable theory. With extra dimensions the particle is not "guided" by some strange phenomena as yet "undiscovered"... it would be moving in a higher dimensional space as a normal particle yet its "projection" into our space is "wavelike"... not simply "guided" along " our "flatspace" in a wavelike motion. IMHO the experimental evidence supports this former position of "higher dimensions". There really never was any physical or experimental evidence for particles moving in a wavelike undulation as far as I can recall. The wavelike nature of particles hails from de Broglie's Matter waves which is quite obviously a reflection of reciprocal space as I have previously indicated in other threads (these waves connect through the reciprocal Hilbert Space but tunnel only slightly into our "flatspace" of three dimensions plus time. In reciprocal space which is connected "harmonically" with our space, we also deal with reciprocal time (frequency). This realm intrudes into our Universe only in the evanescent zone near the "particle" as wavelike behavior. This is the "near-field" where the speed of light has no upper bound. Alternatively in the different geometry of the spreading boson (photons) this is along the wavefront. Essentially the same phenomena in the different spacial geometries the first we call "particles" the other we refer to as "electromagnetic waves" which are simple "stressors of the vacuum" leading to the appearance of "pseudo-charge and pseudo-magnetic fields", which are instantaneous geometry changes in spacetime warping it into "higher dimensions" ("charge" and "magnetism" in instantaneous propagating EM waves should "both" be sourceless). Some have attributed this to gravity (LQG... Smolin and others). I don't think so... it is the much stronger Electromagnetic effect where "gravity" will be as a pseudo-force ... emergent behaviour of the vacuum. We have previously discussed mass as also emerging from advanced and retardend fields.

This is discussed here only in simplified retarded potentials. Mass becomes an "internal" accelration and "gravity" becomes an "external" acceleration, both through extensions of the General Principle of Equivalence. Obviously a better and fuller discussion of the principle is in Nobel Prize winning Wheeler Feynman Emitter-Absorber Theory where advanced and retarded waves "rules". Due to causality we only see the retarded fields. This "frame of reference" forces us to the "frozen" states of "particles" through CPT rules. Seen from the "outside of our Universe" this is only "phase" information (dealing only with frequency). From the "inside" this is our compelling experience of "Time". As you know already I consider that de Broglie's relationships are simply the low velocity consequence of Special Relativity and visa versa. Alternatively they are reciprocally related to each other as a "winding" on spacetime around the light cone. Observe the symmetry in time and space of these "matched" relationships...

See full page

From here there is so much more to consider such as the holographic nature of our Universe, Kondo Phantom Universes and the possible ultimate real nature of "reality" beyond this resonant holographic "flatland". All this happens when you move past "particles" and "locality" as limiting concepts. I know that all this will shut down a couple of minds out there but if elves can't say these things who can?
Wikipedia: Holographic principle
Check out the Weak Holographic Principle.

Cheers

This post has been edited by Good Elf on Oct 7 2006, 03:48 AM

GE, younghand, Yquantum et al,

I fear we are are trying to swallow a whale here. However..

One of the problems I find is that if I feel a prediction disagrees with an experimental result then I will discard the explanation of the 'wrong' prediction. Short posts are a great help when discussing contraversial results.

Good_Elf,
Of your last but one post..pretty much your opening statement..

Linear polarisers at 90 degrees? I think they will block everything.

This repeats the problem in the first sentence and compounds it with another contraversial result ... clarification/evidence please.
-C2.

Hi Confused2,

Linear polarizers at 90 degrees? I think they will block everything.

You misunderstand me, not the same photon at the same time... these are parametrically down-converted entangled photon pairs. You can say nothing about all the blocked photons that are blocked by polarizers... They are all "destroyed". If one photon passes say the zero degree polarizer the other photon (matched) will only pass a ninety degree polarizer. The point is it will always pass the ninety degree polarizer in weak source tests (single photon pairs at a time). All other photons are blocked by the polarizers and play no part in the experiment. The corollary of this is if one photon is passed by the zero degree polarizer if the other polarizer is set to zero degrees as well, it will always block its twin thus collapsing the state of the first twin. And of course visa versa.

This repeats the problem in the first sentence and compounds it with another controversial result ... clarification/evidence please.

Just carrying through. It takes two to entangle. These are polarizers that are only crossed relative to each other they are not on the same paths of the one photon, they are on separate paths (one for each entangled photon)... Sorry about the confusion.

Cheers

Hi All,

Sorry, I think I may have lead us all astray.

http://xxx.lanl.gov/PS_cache/quant-ph/pdf/9903/9903047.pdf

Just looking at fig 2,3,4,5 .. (where it all happens) the implied claim is that the results are exclusive (interference/not interference) .. it kinda looks like they've got both results. Comments?

-C2.

Hi Confused2 and younghand,

I am no "genius" but I will try and sort out the essentials of this experiment. Firstly, entanglement is important in this experiment... it is not important in other dual slit interference experiments. Next polarization is important "between" matched pairs of entangled photons (signal-idler pairs). It is not important to know in this experiment what polarizations any individual photons have since all polarizations will work, what is important is to have a weak source to pass only one pair of "coherent" entangled photons at a time. This way with the right degree of delay we can match up any detected photon in the array sensor D0 with any of the other sensors (D1, D2, D3, D4) and display the results for each set separately as Figs 3,4,5 respectively.

The next point is that all the mirrors are 50% reflecting or transmitting mirrors.... they do not absorb any photons (that operation occurs at the detectors). The mirrors are not polarizers they are just plane semi-silvered front surfaced otherwise transparent mirrors (of exceptional optical quality). Their use is to split the beams randomly towards a detector or towards another mirror 50/50. There is no way to know which photon "bounces off" or is "transmitted through" the mirrors... this happens with a 50/50 chance.

The next point is each photon is producing all the interference in this system independently of all other photons... the "image" of this interference pattern is simply building up one photon impact at a time. All photons have the same interference pattern since they occupy a boson state. Which way information on the other hand carries "particle" information and is essentially different from interference information which can be preserved through endless optical operations without any loss. Only particle operations "lose" information... such as hitting a detector and causing a flash.

The function of the prism is simply to separate the photons "which way" to potentially tell which slit the photons have originated from. It is this "which way" information that can destroy the interference pattern on the D0 screen. This "which way" information is hidden by allowing the interference to "fill the cavity" using the semi-reflected mirrors, the mirror does not allow the experiment to notice "which way" the photon has come and does not block the self-interference. In this way each photon has access to the rest of "itself" in all interference experiments and provide the result on the screen at D0.

The source of the original radiation is a 351 nm argon pumped laser which is coherent radiation. Each "used" photon passes one or other of the slits. At that point is placed a down converter crystal that splits the single laser photon into two coherent and synchronized photons (signal-idler pairs).

The crux of the experiment is that all detections are made long after the photons are detected and destroyed at D0. If they are detected at D3 or D4 the "which path" information is not known (they have termed this quantum erasure). If the photons are detected at detectors D1 or D2 the"which path" information is known and thus the photons at D0 do not form a diffraction pattern or an interference pattern at all. Using the coincidence detector we can provide separate displays for all possible coincidences. We see that idler photons that are not disturbed by detection determining "which way" that reveals the extra information about where the photons have come from form interference patterns. This is as expected (we do not expect that any information gleaned after the fact of destruction of a photon should be able to "reverse" that event in the past). What is unusual is that detection of the equivalent twin idler photon at the later point in time after the signal photon has already been destroyed in the immediate past determines if the signal photon will be part of a set of photons that form self-interference or not. In other words this means that the way in which we process the dual idler photon later in history determines what happened earlier in history to the signal photon. Until we actually measure the through a coincidence counter later in history we cannot know which photon correlates with which picture figs 3,4 or 5. Further... Fig 5 (the bell shaped curve) is NOT a single slit "diffraction" pattern after "which way" information is read from the the idler stream.

Is this what you understand?

Cheers

Hi Good_Elf et al,

Yes, agreeing what is actually observed is a much better way to begin.

Many thanks for the excellent overview.

I'm slightly puzzled by

Is it just that the the shape is not quite as 'resolved' as you'd like or something more fundamental?

That aside .. it's a real headbanger of a thing.

The only sensible thing I can suggest is that the concidence detections are a way of filtering out the 'bad' results to leave only the results that amaze and delight everybody. The amazing outcome is not 'forced' .. merely (very cleverly) detected.. a subtle difference there, perhaps. ++

Never was my 'sig' more appropriate than now .

Thanks again (and best wishes),

-C2.

++ after a bit more thought .. maybe it is every bit as bad as it looks.

This post has been edited by Confused2 on Oct 8 2006, 09:53 PM

Hi Confused2,

Is it just that the the shape is not quite as 'resolved' as you'd like or something more fundamental?
That aside .. it's a real headbanger of a thing.
The only sensible thing I can suggest is that the coincidence detections are a way of filtering out the 'bad' results to leave only the results that amaze and delight everybody. The amazing outcome is not 'forced' .. merely (very cleverly) detected.. a subtle difference there, perhaps. ++

There would be a bit of noise in this experiment. The coincidence detectors would filter out some noise, but I would not expect too much noise given that ordinary dual slit interference does not usually produce too much noise with good quality CW laser sources.

I thought that that remark above might trigger your interest. This is the way I see it... If this was an ordinary dual slit interference experiment simply blocking one of the slits would certainly result in a single slit diffraction pattern. This is like a flautist putting his/her finger over the various holes and modifying the resonant characteristics of the "cavity". This is because the light is coherent and will still diffract through a single slit... admittedly a much smaller effect over a smaller dynamic range but should show clear peaks and troughs in a similar fashion to interference. The entangled photons are a different case altogether. What is happening is the idler photons are being interrogated for "which way" information. This happens even if a counter is not actually operating, there is no need to actually observe the destruction of the "delayed" photon according to the nature of this experiment, no "mind" required to collapse the state (if you get my point). This is "observed to result in this shoddy "bell shaped curve" where the the qubit is removed from the signal photon.

This qubit carries phase information and thus enables the real and imaginary parts of the wave to produce the "pattern" (in step) which is only the square of the projection of the absolute value of the "state vector". This phase is now totally randomized (in the case of entangled photons), as a result of this process. Specific phase information is lost and the effect is as if the beam has lost "coherence" (at least temporarily). Remember it is still actually monochromatic but because the phase is "jumbled" for each individual photon, this changes the effective paths relative to other photons (compare with the single slit situation where the light remains "coherent"). Putting it another way... the photon's particle "core" is "shaken" from its inertial state and "scattered" by the determination of "which way" information of the entangled idler photon's annihilation event.

Of course this is a photon by photon effect. "Destroy" the entanglement of the idler photon by potentially allowing the "which way" information to be read is enough (let it hit an inactive detector if you like). The two entangled photons are connected along the very same wavefront by the phase of these "electric lines of force" in the wave packet. The photons energy is determined by the actual length of these lines and lengthening or shortening any individual lines will redistribute the energy of the system. The signal photon loses this single entangled phase state "instantly" because of the loss of its "other half" and is slightly "bounced" along the wavefront altering paths ever so slightly according to Heisenberg's Uncertainty Relationship. Here is the way it happens ...
Optical Analog of Uncertainty Principle
In this case this happens half way to the screen... or later... this bit is where the "delayed quantum eraser part" comes in. Leave this to next time to discuss. Just see if you can stay with me this far. In Quantum Mechanical terms this is the U(1) abelian Gauge of QED but can be explained in pretty "prosaic terms" this way. Here is a reference to this phenomenon in visual terms.
Gauge Theory and the Standard Model

Individually the signal photons still exist and are still producing interference with itself but since the individual phases no longer match along the wall of the Fourier sensor screen they behave "one at a time" and apparently chaotically producing only the blur where once they would have been sharp peaks and troughs. Only the "envelope" of the pattern of single slit diffraction remains... a separate one for each slit ... slightly displaced from each other if we take the effort by pi phase at its center.

Other please comment and criticism is encouraged.

Cheers

This post has been edited by Good Elf on Oct 9 2006, 07:52 AM

Good_Elf et al,

( we're looking at http://xxx.lanl.gov/PS_cache/quant-ph/pdf/9903/9903047.pdf )
The authors give a mathematical analysis which appears to 'predict' the observed result, ( unfortunately not in a notation I can make any sense of ) .. I suspect analysis would show that the detection of the diffraction interference is beyond the capability of the hardware available.

Unfortunately we don't have details of the slit dimensions and detector type .. I would be tempted to look at these (and the aperture of the lens ) before looking for a more fundamental explanation for the absence of diffraction interference.

I appreciate you (GE) are trying to get away from the 'shut up and calculate' domain into something a bit more user friendly. I suspect this is the reason why you wish to explain the absence of diffraction interference without using the language of quantum mechanics.

I think putting some numbers into this would help a lot.

Even the most basic diffraction builds up 'apparently chaotically' .. I think it would be better to establish the principles using a rather simpler experiment rather than assuming an unproven result and attempting to apply it to anything as complex as this experiment. Sorry.

Best wishes,
C2.

Hi Confused2,

I am pretty sure that the analysis is correct. The phenomena is quite discernible since the slits and the distance between them should be similar for any double slit experiment. The "spread" of the experiment is a "free choice" depending on the slit width and the slit separation. Good optical benches can adjust both and this would be set up "optimally" to span the entire Fourier detector.

The left image shows what might be expected from firing at the screen with a BB Gun and showing no diffraction or interference. He might be wrong but this was also the suggestion made by other authors (apparently A. Wheeler). It really is not an invention of my own mind, this is the practical results. The details you need to work out the optimal result is this...

Double Slit Quantum Eraser Walborn et al
Here you can see (in a similar experiment but quite different) a better image of the result when the qubit is stripped from the idler photon. Also look at this description of the quarter wave plate here...
Wikipedia: Wave plate
It would appear that when you erase "which way" information by only selecting coincident photons (either before or after destruction of the signal photon), you "restore or recover" the interference signal. This second experiment uses the same type of laser and SPDC Crystals so the dimensions at the top of page 3 might also assist.

I hope this helps...

Cheers

This post has been edited by Good Elf on Oct 9 2006, 02:54 PM

Hi Good Elf,

I'm still on
http://xxx.lanl.gov/PS_cache/quant-ph/pdf/9903/9903047.pdf

Because the 'which way' information is read after the interference yes/no detection it would seem to be too late to go back and scatter the photon in the way that you describe. I take for grated that the authors are telling the truth and I see no reason why the 'which path' detector could not be taken to any distance if the concidence detector delay is adjusted to suit. There is a good analysis already available ( QM aka 'shut up and calculate' ) .. to propose an alternative (even a hand waving one) it needs to be 'better' than QM in some way.

A quick look at ..
http://grad.physics.sunysb.edu/~amarch/Wal...tum%20eraser%22
suggest the same problems might well apply.

------------------------------

If we draw a classical Young's DSE we see nice waves .. I suspect we're actually looking at (say) the E field. We can calculate the 'intensity quite easily using basic geometry, but what of GE theory? I have yet to understand any 'link' between GE theory and either EM theory or the single photon case... this may well be my fault, my plea is for very much simpler experiments that might make that link a lot easier to see.

-C2.

Hi Confused2,

Consider the frame of reference of the photon traveling at the speed of light (on the light cone wall). Time is not progressing at all according to Einstein. It "seems" very important from our "external" perspective. Now lets say I destroy the "idler" photon 500 years later in our time than when it's "signal" twin was "recorded" on the Fourier screen. In the frames of the two photons (one long dead from our point of view) and the other about to die 500 years later... There is no difference in the time coordinate between them. These two "events" in the photon frame of reference are "contemporaneous"... they are "Einstein simultaneous". They both "die" at the same time. This matches the fact they were both created at the same "internal" time as well. Notice this is a "non-local" solution to the problem.

Consider the Wheeler-Feynman Advanced and retarded wave solution for this problem. We are only recording and observing the retarded solution. Look at this image...

The reference comes from this page here...
2. Wheeler-Feynman Absorber Theory see link Fig.1.

In Fig. 1 the time coordinate runs vertically and one linear dimension runs from left to right. The lead into this is here...
1. Introduction

Once again it is not my idea it is an accepted way to interpret the problem and a compliant way to interpret Quantum Mechanics. This deals with it as a non-local theory of Electromagnetism. CPT arises from the apparent quandary of the inability to "perceive" time symmetry and the advanced potential waves. In our Universe we see these retarded waves and one could complete this schema in higher unseen dimensions with advanced waves running backwards in time relative to our perception of time. Causality enforces a barrier since we are denizens of this "spatial cavity". In this way a complete "event" is a landscape portrait of all time and space as a sum of the retarded and the advanced solutions (not just one or the other). This "perspective" could only be gained using the concept of "reciprocal space" and the "reciprocal time" of frequency... the conjugate Fourier domain of a "Particle Universe". This perspective from outside the light cone treats time as "phase". It has led to a tremendous number of technical advances in Fourier Technologies and obviously has a special place in the way this theory sits within Electromagnetic Theory and in Feynman's Quantum Electrodynamics. So you really do not need to "shut up and calculate" there have been solutions for a long time and they involve a very old Nobel Prize (or two).

I have not couched all my discussions in this "retro" fashion for no reason... it is a legitimate way to actually view Quantum Theory and seems to me a almost "hidden way". This is why Bhomian Mechanics actually appears to work and the Holographic Universe "seems" to be a real phenomenon. Certainly much of the so called "discoveries" in information related to quantum entanglement points in this direction to this "different landscape". As noted above it even reinterprets "a solution to a number of "interpretational'' quantum mechanical paradoxes (The E-P-R paradox[8], The Schrödinger's Cat Paradox, Wheeler's Delayed Choice Experiments, etc."... I would also add in the Aharanov-Bohm and the Aharanov-Cashir Experiments. All of these have Bhomian Interpretations. This includes this present problem of the Delayed Choice Quantum Eraser... this is the "Wheeler's Delayed Choice Experiments" mentioned above since Wheeler was the first one in the literature to propose this "test". They are not able to be explained easily with Quantum Mechanics which are missing the phase relationships. I could go on but Quantum Mechanics has some difficulties with at least the Copenhagen Interpretation and just 'shut up and calculate' but why do this when there already exists a "perfectly good" hidden variable theory that just is waiting in the wings with all the trimmings just begging to be used. These "hidden variables" are the "hidden dimensions" of "String Theory". This is the reason why we are going around in circles of ever decreasing radii until we fly up our own fundamental orifices regarding these matters. This theory can potentially "lose" all those Quantum Postulates and instead of this...

we would have this...

In other words the successes of Circuit QED is no accident.
Links for Circuit QED
These trapped photons are not just strange solutions to QED but represent a "mechanical" analog of the nature of our true reality and cavity oscillations of the quantum EM classical field equations. It is the success of Photonics that is begging us to move away from a strict QM point of view and to accept particle and wave dynamics instead of pure statistics. The statistical approach has led to some "true" statements but for a lot of "dumb" reasons... in the end it ends up being couched in either semi-religious terms like the Anthropic Principle, or in counterintuitive quantum "miracles" that begger understanding. IMHO Einstein was right all along... "God" does not play dice with man... he plays a "flute" instead. It is not as if I am handing you a "poison chalice" this is "The Grail".

Cheers

Hi Good Elf,

Re Circuit QED.. can we start with (say) an electron in a potential well just to see what it looks like?

-C2.

Hi Confused2,

This is the side salad for the main course. As interesting as it is, I think we should stay on this thread's topic for now.

For those interested... A productive view of Circuit QED would start with the Fermi Energy of non-interacting fermions and then to investigate the bosonic state of matched fermion pairs and what this may mean.
Wikipedia: Fermi Energy
That is the "shells" in atoms... the Aufbau Principle and the individual shells sub-shells and their numbers and their orientations and relationships to the quantum numbers. This reference has a simple treatment as a box with a particle in it.
Wikipedia: Atomic Orbitals
All this you probably already know. Most instructive is to concentrate on the role of the photons themselves (bosons). There is a FAQ where the authors describe what they believe they have achieved...
Circuit QED FAQ
I am interested to continue with the thread if you are still following so far... "Problem with the two slit experiment... Observing later".

Cheers