Problem with the two slit experiment, Observing later

relevant info
http://www.physics.ubc.ca/~berciu/PHILIP/C...WI03/index.html
"Quantum Mechanics on the Large Scale"

http://www.google.com/search?hl=en&q=relat...FILES/baccia.ps
The Role of Decoherence in the Foundations of Quantum Mechanics

Hi Good Elf et al,

I do agree my little camera can't analyse the frequencies you or I might be interested in - I'm not so sure about TRoc though.

Hopefully it will be OK with everyone if we move (slowly!) into the realms of 'predict and test' using the results we already have ..

A 'wavelength and geometry' analysis of the DSE starts here:-
http://webpages.ursinus.edu/lriley/courses...res/node30.html

Points of particular interest to me are
1/ "Provided the distance between the slits and point P is less than the coherence length (see Eq. 2.78 ) of the source, interference effects are observed, because the path lengths of traversed by the waves from the two slits reaching point differ. "
Hands on experience with a laser shows that with a laser you get interference absolutely everywhere and with any other source it's rather difficult to find. Possibly my brown (beer bottle) filter is less than ideal for generating monochromatic light. I think it would be useful to look at the way Kennedy-Thorndike produced their (obviously) coherent light. Also I am still not clear what the full function of that first slit is.
2/ To get round the need to compare the path differences to a point on the screen and to give a result result solely in terms of angle theta they have used the approximation
r1-r2 ~= dsin (theta) ..
I would have preferred an analysis to an actual point on the screen but since this is all done for us I'm not going to complain too much .. as long as we see the 'trick'.

The 'starter' analysis leads logically to a full blown analysis (including slit width) here:- http://webpages.ursinus.edu/lriley/courses...res/node32.html

Comments invited.

Best wishes,
-C2.

A while back TRoc suggested that we could open up a slit (or two) in our 'screen' and make a either a diffraction pattern or a secondary DSE within a DSE. The hero of the foregoing analysis rather lost the possibility of analysing this situation by losing the real path length difference in his approximation r1-r2 ~= dsin (theta) .. bit of a nuisance that. My analysis here ( http://forum.physorg.com/index.php?showtop...ndpost&p=183204 ) stays with the path length difference right up to the screen (hence needs to know the distance to the screen). In fairness I haven't done a full integration over the width of the slits (just assumed point sources) despite this simplification IMHO retaining the path length to the bitter end gives a more 'physical' result. By retaining true path length (rather than angle) we can open up new slits in the screen and analyse a secondary DSE with no conceptual problems. I will attempt this analysis if challenged but there's not much point if (as I suspect) nobody will attempt to follow it.

I haven't forgotten extra dimensions etc. but I am starting to feel that we need to establish a degree of competence and confidence in the result we are seeking so we can more easily distinguish between reality and red herring.

Best wishes,
-C2.

Hi Confused2,

We have been all through this before. Kennedy-Thorndike Interferometer, it is an Interferometer Experiment not a DSE. It gave a null result. Interference has nothing to do with path length as such otherwise this process would fail for single photons, anyway this experiment has to do with detecting aether. It is very clear from all the previous discussion photons self interfere not mutually interfere. You do not need lasers to do the DSE, any old monochromatic light will do as long as you allow far field conditions to apply it will become spontaneously partially coherent (some refer to it as "clumping"). I prefer to think of this as the principle of least action.
Bandwidth Limits
This is clearly an expression of the Heisenberg Uncertainty Relationship. But like the lecturer himself says this is not "uncertainty" it is a classical effect of a quantum phenomenon.
Wikipedia: Quantum Tunneling
Wikipedia: WKB Equation

What "trick"? I do not see your point there. It is a function you evaluate throughout all space but obviously is only applicable within certain limits. These limits are too restrictive to be fully meaningful if we want to go anywhere "interesting". I would hope that you could take this as given.

In other respects the maths you have dug up is quite adequate... very adequate. It is not a "starter" analysis, your path length concept it is not a way to an understanding of of the general phenomena, the optical theory needs to be accepted in whole. This page format is not capable enough to discuss the maths. The maths is in the pages you have tendered (it is a full course). I have grown very weary of this circular argument. No offense intended but we better drop this thread... It is going nowhere and nobody is following anyway. I can't share your enthusiasm. I am not a mathematician anyway (not that anyone need be with Physics... this is the standard treatment just taken a step further). The principles given are all that can be discussed.

I do not have the time to analyze herrings of any color. There are other exciting developments and I work for a living so I need my time to keep up. While we have been talking on this thread there have been so many interesting things happening that herrings should be the last things on your mind.

We are like some myopic reader closely inspecting the alphabetical characters on the page for hidden patterns when the overall paper's informational content is missed entirely. For me the important point is extra dimensions.

Cheers

This post has been edited by Good Elf on Mar 26 2007, 04:06 PM

I do not have the time to analyze herrings of any color. There are other exciting developments and I work for a living so I need my time to keep up. While we have been talking on this thread there have been so many interesting things happening that herrings should be the last things on your mind.

We are like some myopic reader closely inspecting the alphabetical characters on the page for hidden patterns when the overall paper's informational content is missed entirely. For me the important point is extra dimensions.

Cheers

Bohm has talked about folded and unfolded structures. if you view the genome as a folded structure that unfolds as it develops how many dimensions would you use to characterize it? there are 30,000 genes and probably 100,000 small RNAs that are important in human development. Incidentally I've been checking the genetic information content of some important genes I designed all day today.

This post has been edited by Neil Farbstein on Mar 27 2007, 04:57 AM

Hi Neil, Confused2 et al,

Umm... those are "parametric dimensions" not spatial dimensions, sort of like the ones Zephir speaks of for his theory LQG. Bohmian Mechanics are provisionally only hidden variables so they may or may not be actual dimensional spaces, its a free choice in Mathematics. Physics though has to face a number of additional experimental facts that add more restraints on what these parameters might be. I think these are harmonically connected dimensional spaces occurring in triplets, nine spatial and one temporal making 10 "Einstein" dimensions in an extended spacetime only three of which we are ordinarily able to see and another reciprocally embedded six dimensional object that share these three dimensions with us (sub-atomic particles and their supersymmetric partners... their accompanying "harmonic shells"). It does not stop there though... there are more in a Holographic "Optical" Universe based on Anti-de Sitter spaces (AdS/CFT) of Juan Maldacena.
Wikipedia: AdS/CFT correspondence
These fit with Fourier Theory like a hand in a glove.

Space is a closed "box". This is like a bug on the inside of a balloon. We are like little bugs forced to wander on the inside in a "flatspace". It is unbounded finite. No way out through any translation or rotation. Our Universe is like that and I believe that particles are like that too. "As above so below". One extreme example is a wheel with spokes that is spun such that the rim which is contrived to be massless reaches the speed of light. length contraction occurs in the direction of the tangent while there is no contraction along the radii (spokes), standard Special Relativity. Combine this with Berry Phase the external circumference can shrink to nearly zero since this is the length in the direction of motion while the interior volume is dictated by a Lorentzian Geometry of Instantons. This problem has been analyzed previously on this thread. because of relativistic rotation through an angle arctan(V/C), no world line can leave the interior of this space and the space on the outside may or may not have positive definite volume. This boundary is a light cone wall, a "stationary state" in which information usually does not pass unless it is by a quantum process where it tunnels out through a resonance. Intrinsically linked with Singular Optics and the experimental work of Dr. Taco Visser. This is just like an electron where it has no measurable volume, other particles have different properties. Solitons also can be one end of a spectrum of phenomena which includes particle anti-particle creation and Lorentz Invariant CPT.

Cheers

IMHO this finally severs any tenuous link to experimental evidence.

-C2 .

Hi Confused2,

IMHO this finally severs any tenuous link to experimental evidence.

I really do not understand why. If it was simple path length, a single photon could not engage in interference since as you have acknowledged yourself in the past, that the Hanbury-Brown Interferometer indicates clearly single photon interference would be impossible with vastly different length arms of the instrument. The paths lengths down the different arms can be made so different that the single photon has no hope of self interference it that was the reason for this phenomena. The timings are such that if this was a traveling disturbance that "mixed" with itself this can be arranged such that the photon "interference" which is undeniable, can't physically occur if the different paths down each tube can never cross in time on in space. Therefore it must be something else and it is related to a single photon since interference fringes can occur even with single photons building up the picture. This is just a certain stubbornness that we humans have to not accept what we usually cannot see. Yet this behavior of photons can be proven.

This quantum interference exists in the space of the instrument at all times waiting for the passage of the photon to play a role. To me the "interference" is simply the phenomenon of standing waves in a cavity, the cavity itself has created an unseen geometry of its own accord that exhibits a special geometry to every photon (through the superposition of states) and is not the photon itself that is the cause of interference as traveling photon waves. It is possible that the dual nature of matter itself is what does this (its supersymmetry mentioned previously which has a boson for every fermion and a fermion for every boson).

Take for instance a single proton particle that is composed of quarks (fermions). This is always surrounded by a hybridized series of bosonic resonant cavities and this structure can trap electrons and photons. This is atomic theory. Even if you strip away all electrons and photons this structure still exists "unseen". Even the proton (and other particles), when interacting with very energetic photons, can trap them in its "nucleus". In the case of single photon experiments the passing of the single photon through this "spatial structure" simply "illuminates it". The detection of the photons provides us with tangible mapping of the spaces. We have seen these structures in pictures I have supplied previously in cavities from excellent experimental work. These are space filling structures.

... click to enlarge...

It is "nothing" to go from that concept to see that any cavity of any size that is composed of "fermion assemblage" walls has associated bosonic cavities already in place as a "dual". There are a few rules of thumb that work quite well and the DSE simple formula is one of them. Usually we think of atomic cavities as the only kind but since electromagnetism comes in all wavelengths then this dual structure can fill any space resonantly.

Cheers

This post has been edited by Good Elf on Mar 27 2007, 04:11 PM

Due to the total lack of demand .. the C2 optics lab is back.

Young's blobs

... click to enlarge...


Young's blobs - detail

... click to enlarge...

Looking at the detail picture- my explanation..
Let us guess that the big blob in the bottom right is (say) positive phase addition (plus 'burn'), this leaves the ring above it as negative phase addition. The finer lines are alternating positive and negative peaks. The positive peaks have added to the blob (positive) and subtracted from the ring, conversely the negative fine detail peaks have added to the ring and subtracted from the blob.

As far as I am aware - standing waves have magnitude but no phase - I invite a standing wave explanation.

The colours are the result of 'something else' which I will explain if given no alternative.

Best wishes,
-C2.

Umm... those are "parametric dimensions" not spatial dimensions, sort of like the ones Zephir speaks of for his theory LQG. Bohmian Mechanics are provisionally only hidden variables so they may or may not be actual dimensional spaces, its a free choice in Mathematics. Physics though has to face a number of additional experimental facts that add more restraints on what these parameters might be. I think these are harmonically connected dimensional spaces occurring in triplets, nine spatial and one temporal making 10 "Einstein" dimensions in an extended spacetime only three of which we are ordinarily able to see and another reciprocally embedded six dimensional object that share these three dimensions with us (sub-atomic particles and their supersymmetric partners... their accompanying "harmonic shells"). It does not stop there though... there are more in a Holographic "Optical" Universe based on Anti-de Sitter spaces (AdS/CFT) of Juan Maldacena.
Wikipedia: AdS/CFT correspondence
These fit with Fourier Theory like a hand in a glove.

Space is a closed "box". This is like a bug on the inside of a balloon. We are like little bugs forced to wander on the inside in a "flatspace". It is unbounded finite. No way out through any translation or rotation. Our Universe is like that and I believe that particles are like that too. "As above so below". One extreme example is a wheel with spokes that is spun such that the rim which is contrived to be massless reaches the speed of light. length contraction occurs in the direction of the tangent while there is no contraction along the radii (spokes), standard Special Relativity. Combine this with Berry Phase the external circumference can shrink to nearly zero since this is the length in the direction of motion while the interior volume is dictated by a Lorentzian Geometry of Instantons. This problem has been analyzed previously on this thread. because of relativistic rotation through an angle arctan(V/C), no world line can leave the interior of this space and the space on the outside may or may not have positive definite volume. This boundary is a light cone wall, a "stationary state" in which information usually does not pass unless it is by a quantum process where it tunnels out through a resonance. Intrinsically linked with Singular Optics and the experimental work of Dr. Taco Visser. This is just like an electron where it has no measurable volume, other particles have different properties. Solitons also can be one end of a spectrum of phenomena which includes particle anti-particle creation and Lorentz Invariant CPT.

Cheers

How could the rim be massless? What do you obtain if real world conditions are used in your equations?

Hi Neil,

Real world results have a limit to the conditions that would apply to light or to photons. This is the same real world conditions where light actually follow the same geodesic as a rock projected in spacetime... The only difference between a massless photon and a rock "falling" through spacetime is is the difference in velocity. As V(rock) -> C the geodesic of the rock and light "converge". This has been known since the time of Galileo when he reputedly dropped two differently sized cannonballs from a great height and noted they hit the ground at the same time proving the "physics" of Aristotle was wrong (that things fall at different rates proportional to their mass)... nobody ever bothered to check and see that all objects (in the absence of friction) fall at the same rate.

Much is made of "curved spacetime" but to notice any curvature there is an implicit assumption that "straight" actually means the line along which light travels. Being "immersed in curved spacetime will not allow you to "see" departure from "straightness" and so a curved trajectory implies that we are dealing with two different frames of reference. The frames may be in relative acceleration or they may not. This result is very important and shows the relationship between Special Relativity and even massless particles. Gravity is a pseudo-force since everything is affected in the same way so departure from 'straight' indicate "forces" to many, however this must be qualified by first comparing the two frames of references being discussed.

This principle also applies to photons and is proven by the deflection of light by gravitating bodies, one of Einsteins classic predictions. Space tells particles how to move and mass tells space how to curve. The subtlety is a "straight line " drawn in a curved manifold will possibly appear straight from another manifold in relative acceleration and naturally visa versa. The general principle of equivalence. It is a common misconception that most people believe in Aristotle and think that mass tells particles how to move. This is taught to us as children and is part of our schooling but is totally wrong. Much of this result indicates that a rock and a photon fall at exactly the same rate. So when I am speaking of a rotating frame of reference the massless part of it refers to the behavior of light in the geometry not of matter. Still it is just a limiting case. Now as to who sees acceleration and who does not see the acceleration is the next important result. Two observers may measure relative accelerations from different frames of reference of another particle in relative motion but it does not follow that we have a non-inertial situation. In the case of rotating frames of reference a great deal of care is required to correctly determine what is happening. So the "rim" of such a rotating system initially suggests that all co-moving photons are in a rest frame... I don't think so... This would be an incorrect conclusion.

In the case stated, analysis of this phenomenon indicate that Special Relativity is all that is necessary to analyze the problem provided this is correctly treated. So we are only left to determine what it is that makes light move along such geodesics since these do occur in nature, even in such simple optical systems. These lead to stationary states and photon trapping. Previously I have referred to papers that deal with this state. I do not have the reference here but I will find it later when I am able to search through my references.

Cheers

Hi Neil Farbstein,

This is the reference...

Please look at the figures as well, they are very helpful. It is easy to understand from this reference how the topology of space can change under rotation.

Cheers

This post has been edited by Good Elf on Mar 28 2007, 03:47 PM

Real world results have a limit to the conditions that would apply to light or to photons. This is the same real world conditions where light actually follow the same geodesic as a rock projected in spacetime... The only difference between a massless photon and a rock "falling" through spacetime is is the difference in velocity. As V(rock) -> C the geodesic of the rock and light "converge". This has been known since the time of Galileo when he reputedly dropped two differently sized cannonballs from a great height and noted they hit the ground at the same time proving the "physics" of Aristotle was wrong (that things fall at different rates proportional to their mass)... nobody ever bothered to check and see that all objects (in the absence of friction) fall at the same rate.

Much is made of "curved spacetime" but to notice any curvature there is an implicit assumption that "straight" actually means the line along which light travels. Being "immersed in curved spacetime will not allow you to "see" departure from "straightness" and so a curved trajectory implies that we are dealing with two different frames of reference. The frames may be in relative acceleration or they may not. This result is very important and shows the relationship between Special Relativity and even massless particles. Gravity is a pseudo-force since everything is affected in the same way so departure from 'straight' indicate "forces" to many, however this must be qualified by first comparing the two frames of references being discussed.

This principle also applies to photons and is proven by the deflection of light by gravitating bodies, one of Einsteins classic predictions. Space tells particles how to move and mass tells space how to curve. The subtlety is a "straight line " drawn in a curved manifold will possibly appear straight from another manifold in relative acceleration and naturally visa versa. The general principle of equivalence. It is a common misconception that most people believe in Aristotle and think that mass tells particles how to move. This is taught to us as children and is part of our schooling but is totally wrong. Much of this result indicates that a rock and a photon fall at exactly the same rate. So when I am speaking of a rotating frame of reference the massless part of it refers to the behavior of light in the geometry not of matter. Still it is just a limiting case. Now as to who sees acceleration and who does not see the acceleration is the next important result. Two observers may measure relative accelerations from different frames of reference of another particle in relative motion but it does not follow that we have a non-inertial situation. In the case of rotating frames of reference a great deal of care is required to correctly determine what is happening. So the "rim" of such a rotating system initially suggests that all co-moving photons are in a rest frame... I don't think so... This would be an incorrect conclusion.

In the case stated, analysis of this phenomenon indicate that Special Relativity is all that is necessary to analyze the problem provided this is correctly treated. So we are only left to determine what it is that makes light move along such geodesics since these do occur in nature, even in such simple optical systems. These lead to stationary states and photon trapping. Previously I have referred to papers that deal with this state. I do not have the reference here but I will find it later when I am able to search through my references.

Cheers

its amazing how much physics you keep track of. What in a rest frame in your exapmle Elf?

Real world results have a limit to the conditions that would apply to light or to photons. This is the same real world conditions where light actually follow the same geodesic as a rock projected in spacetime... The only difference between a massless photon and a rock "falling" through spacetime is is the difference in velocity. As V(rock) -> C the geodesic of the rock and light "converge". This has been known since the time of Galileo when he reputedly dropped two differently sized cannonballs from a great height and noted they hit the ground at the same time proving the "physics" of Aristotle was wrong (that things fall at different rates proportional to their mass)... nobody ever bothered to check and see that all objects (in the absence of friction) fall at the same rate.

Much is made of "curved spacetime" but to notice any curvature there is an implicit assumption that "straight" actually means the line along which light travels. Being "immersed in curved spacetime will not allow you to "see" departure from "straightness" and so a curved trajectory implies that we are dealing with two different frames of reference. The frames may be in relative acceleration or they may not. This result is very important and shows the relationship between Special Relativity and even massless particles. Gravity is a pseudo-force since everything is affected in the same way so departure from 'straight' indicate "forces" to many, however this must be qualified by first comparing the two frames of references being discussed.

This principle also applies to photons and is proven by the deflection of light by gravitating bodies, one of Einsteins classic predictions. Space tells particles how to move and mass tells space how to curve. The subtlety is a "straight line " drawn in a curved manifold will possibly appear straight from another manifold in relative acceleration and naturally visa versa. The general principle of equivalence. It is a common misconception that most people believe in Aristotle and think that mass tells particles how to move. This is taught to us as children and is part of our schooling but is totally wrong. Much of this result indicates that a rock and a photon fall at exactly the same rate. So when I am speaking of a rotating frame of reference the massless part of it refers to the behavior of light in the geometry not of matter. Still it is just a limiting case. Now as to who sees acceleration and who does not see the acceleration is the next important result. Two observers may measure relative accelerations from different frames of reference of another particle in relative motion but it does not follow that we have a non-inertial situation. In the case of rotating frames of reference a great deal of care is required to correctly determine what is happening. So the "rim" of such a rotating system initially suggests that all co-moving photons are in a rest frame... I don't think so... This would be an incorrect conclusion.

In the case stated, analysis of this phenomenon indicate that Special Relativity is all that is necessary to analyze the problem provided this is correctly treated. So we are only left to determine what it is that makes light move along such geodesics since these do occur in nature, even in such simple optical systems. These lead to stationary states and photon trapping. Previously I have referred to papers that deal with this state. I do not have the reference here but I will find it later when I am able to search through my references.

Cheers

its amazing how much physics you keep track of. What's in a rest frame in your example Elf?

Light Seems to Pass through Solid Metal

http://news.yahoo.com/s/livescience/200703...fJT.NlG5GnMWM0F

LL