QED/Quantum Mechanics: Probability or Spatial Function?

In summary: Feynman also discusses the possibility of an infinite number of detection points due to the wave nature of light. However, there are questions about whether this would still hold true if multiple probes were set up simultaneously. Additionally, Feynman's explanation of reflection as a wave function phenomenon seems contradictory to the particle paradigm. The concept of a Spacial Matrix is proposed as an alternative theory, which could potentially eliminate many paradoxes in quantum mechanics. However, further understanding and research is needed to fully comprehend the complexities of quantum mechanics.
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TL;DR Summary
Can the quantum nature of reality be based on a spacial matrix function rather than the probability function of QED/Quantum Mechanics?
In "QED, The Strange Theory of Light And Matter" Richard Feynman describes the probability path of a single photon emitted from a source, reflected from a mirror surface, and finally reflected to a probe detector. This path is the least time path relative to the probe/viewer, determined by the phasor angle of the time/probability path. See diagram below. Notations added.

As we all know from experience, the detection point is determined wherever the probe/viewer is stationed. Therefore, in principle, the number of possible detection points are infinite in spacial locations, viz., an infinite number of the least time paths are possible. The orthodox particle theory of light would negate such a possibility, but the wave nature of light would seem to allow it. Of course, such detections by eye are a result of many emissions of photons.

But a question arises that, in theory, if we could set up an infinite number of different probes would we detect the same "one" photon at all the infinite probe locations "simultaneously" (ignoring the spatial distance of time delay of the different locations), or is this detection dependent on the finite quantum packet of the photon "particle" and therefore detectable by only one probe? Presumably then, the shortest least action path would be that detection point. Although, this could also possibly be a wave function of a finite quantum packet of the photon.
Has a similar experiment ever been conducted?

However, it is odd that the experiment is conducted under the assumption that reflection occurs as a wave function phenomenon, given that a mirror surface is a reflector of light waves, which can therefore be predictably determined by the least time path, and disregarding a particle probability consideration. The least action path, relative to reflection paths, seems contradictory to the particle paradigm. It also seems to unnecessarily complicate the understanding of Nature by probability functions. Feynman himself concedes this Strange conundrum in the very title of his book. A more sensible paradigm would be that a Spacial matrix is the actual function of "motion", energy, and matter themselves, albeit, one that cannot presently be defined by orthodox science. It is true that the equations in the QED and Quantum Mechanics models are highly precise in their predictions, but this would be expected, given that the elements of their equations are based on known experimental constants and extrapolated therefrom; viz. that such predictions are simply mathematical logical extensions. The same can be said of particle theory creation via collider experiments, thereby creating mathematical "phantom" particles that normally have no reality in Nature, except as logical extensions of synthetic conditions. Similarly, in Quantum Mechanics, the Spacial Matrix concept would eliminate the paradox of an interference pattern creation in the two slit experiment created by a series of single shot electrons. And the use of probes to detect which slit the electron emerges from is nonsensical, since it introduces a type of "nodal" point in the wave pattern of the wave/particle as a function of space, thus creating a new wave pattern that disrupts the interference path. Indeed, a whole host of paradoxes would be eliminated by this Spatial Matrix concept.

Other concepts would be required to make full sense of this Matrix concept, but in the interest of keeping this simple and short, it is left as is here.

Probability Paths of Photon
 
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:welcome:

I can't follow what you are asking. Are you asking for an explanation of Feynman's diagram? Or, asking us to review your own alternative theory to QED?
 
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  • #3
Inqur said:
Feynman describes the probability path of a single photon emitted from a source, reflected from a mirror surface, and finally reflected to a probe detector. This path is the least time path
No. It is all paths, not just the least time path. All possible paths contribute.
 
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Inqur said:
Indeed, a whole host of paradoxes would be eliminated by this Spatial Matrix concept.

I would say, that a whole host of paradoxes you see would be eliminated if you learned how QED or QM actually work. The book by Feinman is a pop-sci book, and reasoning based on those will not lead you anywhere.
 
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  • #5
As has been noted you do not understand Feynman's (nor, for that matter, Fermat's) principal. This does not mean your attempt to understand it is foolish.
As Feynman himself pointed out nobody really understands Quantum Mechanics even after a lifetime of contemplation. So maybe claims of easy victory are at least presumptuous.
 
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Inqur said:
TL;DR Summary: Can the quantum nature of reality be based on a spacial matrix function rather than the probability function of QED/Quantum Mechanics?

In "QED, The Strange Theory of Light And Matter" Richard Feynman describes the probability path of a single photon emitted from a source, reflected from a mirror surface, and finally reflected to a probe detector. This path is the least time path relative to the probe/viewer, determined by the phasor angle of the time/probability path. See diagram below. Notations added.
I agree with weirdoguy: Feynman is attempting to describe how to do an integration over field variables in space-time on a High School level using little arrows. He did a very good job, but the details are far beyond anything you would understand from High School. My Graduate level (well, perhaps advanced Undergrad) Particle Physics text is very bare bones and it still takes him 200 pages before he introduces how to do this for a very simplified QFT model. (And you already have to know a lot of Linear Algebra and Quantum Mechanics before you could even get there.)

Don't take Feynman too literally here. He is not teaching you how to build a Ferarri ...he's showing you a model of a do-it-yourself go-cart.

-Dan
 
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Inqur said:
In "QED, The Strange Theory of Light And Matter" Richard Feynman describes the probability path of a single photon emitted from a source, reflected from a mirror surface, and finally reflected to a probe detector. This path is the least time path relative to the probe/viewer, determined by the phasor angle of the time/probability path. See diagram below. Notations added.

As we all know from experience, the detection point is determined wherever the probe/viewer is stationed. Therefore, in principle, the number of possible detection points are infinite in spacial locations, viz., an infinite number of the least time paths are possible. The orthodox particle theory of light would negate such a possibility, but the wave nature of light would seem to allow it. Of course, such detections by eye are a result of many emissions of photons.

But a question arises that, in theory, if we could set up an infinite number of different probes would we detect the same "one" photon at all the infinite probe locations "simultaneously" (ignoring the spatial distance of time delay of the different locations), or is this detection dependent on the finite quantum packet of the photon "particle" and therefore detectable by only one probe? Presumably then, the shortest least action path would be that detection point. Although, this could also possibly be a wave function of a finite quantum packet of the photon.

Has a similar experiment ever been conducted?

Actually, yes. A single quantum of light (Fock state, N=1) can be detected in one and only one location - even if there are 2 or more places it could appear.

To perform this experiment, you start with an entangled pair of photons (Fock state, N=2) and detect one of the pair. This means there is another photon somewhere, which is "heralded" by the detection of the first. Then, we look for the remaining one to be detected in one or both of two target detectors where it has been concentrated. You can guess the result (which was measured to accuracy of 377 standard deviations), and here is the reference:

http://people.whitman.edu/~beckmk/QM/grangier/Thorn_ajp.pdf
Observing the quantum behavior of light in an undergraduate laboratory (2004)
"Spontaneously downconverted light is incident on a beamsplitter and the outputs are monitored with single-photon counting detectors. We observe a near absence of coincidence counts between the two detectors—a result inconsistent with a classical wave model of light, but consistent with a quantum description in which individual photons are incident on the beamsplitter."

And another:

https://arxiv.org/abs/1412.7790
Experimental Proof of Nonlocal Wavefunction Collapse for a Single Particle Using Homodyne Measurement (2014)
"A single quantum particle can be described by a wavefunction that spreads over arbitrarily large distances, but it is never detected in two (or more) places. This strange phenomenon is explained in quantum theory by what Einstein repudiated as “spooky action at a distance”: the instantaneous nonlocal collapse* of the wavefunction to wherever the particle is detected."*Note that the use of the word "collapse" is objected to by some physicists, who deny there is such a physical process. Within the community, this has a generally accepted meaning - that a random measurement result is selected/detected from all of the available possible quantum outcomes.
 
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I'll just add for others reading that in the Feynman sum-over-paths approach even the word "path" isn't quite accurate.

For massive particles in the non-relativistic case the paths ##x(t)## have singular derivatives at each point, so they are "infinitely jagged". These paths are not really trajectories in the classical physics sense of the word, but the kind of pathological functions investigated by mathematicians at the end of the 19th century.

In the relativistic case the "paths" aren't even functions at all, but distributions. So if ##x(t)## is some path, the objects in the path integral are functionals:
##F:x(t) \rightarrow c, c \in \mathbb{R}##

These distributions have odd properties like being defined in a Riemannian space not the Lorentzian spacetime of actual physics, or each path having infinite kinetic energy even though the actual electron always has finite kinetic energy experimentally.

So ultimately it's best not to think of these objects as being related to any actual motion of the electron, but more so formal objects for calculations.
 
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Now is a good time to close this thread. It seems many posters have answered the OPs original question.

Thank you all for contributing here.

Jedi
 
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