Two-Slit Experiment: Photon Energy Shift from Gravity

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Discussion Overview

The discussion centers on the implications of performing the two-slit experiment vertically, particularly regarding the potential energy shifts of photons due to gravitational effects. Participants explore how these shifts might affect the detection of photon paths and the feasibility of measuring such energy differences.

Discussion Character

  • Exploratory
  • Debate/contested
  • Technical explanation

Main Points Raised

  • One participant suggests that a vertical two-slit experiment could reveal red or blue shifts in photon energy due to gravity, depending on the path length from each slit.
  • Another participant argues that the energy loss from a photon is consistent regardless of the slit it passes through, indicating that the energy levels observed would not reveal the path taken.
  • A different viewpoint proposes that single photon interference could be analyzed using a photoelectron material, questioning the ability to detect the minute energy differences involved.
  • One participant emphasizes that the net vertical movement in the gravitational field is what matters, asserting that it remains unchanged regardless of the slit used.
  • Another participant challenges the idea that a photon passing through the higher slit would gain energy upon descending, suggesting that any gain would equal the loss incurred earlier.

Areas of Agreement / Disagreement

Participants express differing views on whether the energy of photons can indicate which slit they passed through, with some asserting that it cannot while others propose that it might. The discussion remains unresolved regarding the implications of gravitational effects on photon energy in this context.

Contextual Notes

Participants note the challenges in measuring tiny energy differences and the assumptions regarding the behavior of photons in a gravitational field, which may not be fully addressed.

Emissive
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If we perform the two slit experiment vertically - so the slots are above one another - we should observe a small amount of red / blue shift in the energy of the photons when they hit the screen (due to gravity). The path length from each slit is not symetric so the arriving photons energy would vary depending on the route. This would avoid measuring the photons at the slits but still - over time - assuming the equipment was sensitive enough - predict which path a photon took.

Would the arriving energy level of the photon be a combination of the energies of a photon going through both the two slits path? Or always be one of the two energy levels required for it go down either path?
 
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The energy loss from a photon is the same no matter which slit it went through. All you would know is that the photons hitting the upper part of the sensor are redshifted a little bit more than the lower part, not which path they took.
 
How about single photon interference with the backstop an photoelectron material. If the electron comes through the top slit and down to a central, phase additive line, then an electron is emitted. Otherwise, through the bottom slit, the energy is insufficient.

Personally, I'm not sure that you can get an narrow enough bandwidth to detect the tiny, tiny energy difference.
 
MRBlizzard said:
How about single photon interference with the backstop an photoelectron material. If the electron comes through the top slit and down to a central, phase additive line, then an electron is emitted. Otherwise, through the bottom slit, the energy is insufficient.

Personally, I'm not sure that you can get an narrow enough bandwidth to detect the tiny, tiny energy difference.

You're missing the point of the experiment. He's proposing that you can detect which slit the photon went through by measuring its energy upon detection. But this won't work. A photon detected 1 inch above the center of the screen will have an identical amount of energy no matter which slit it came through. It's not path length that matters, it's net vertical movement in the gravitational field, and that remains the same no matter which slit it goes through.
 
it's net vertical movement in the gravitational field, and that remains the same no matter which slit it goes through.

Why doesn't the photon passing through the higher slit gain energy upon descending to the middle of the screen, where the interference occurs?
 
MRBlizzard said:
Why doesn't the photon passing through the higher slit gain energy upon descending to the middle of the screen, where the interference occurs?

Who said it doesn't?
But first it must lose energy because it passed through the top slit, so the gain is equal to the loss. And the reverse is true for one passing through the bottom. First it gains energy, then it loses it. So whether it passes through the bottom or the top the energy is the same.
 
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