B Double slit experiment question

[ElanaC]

Hi, I have two questions concerning the double slit experiment in the scenario where we fire one photon at a time and it interacts with itself to create an interference pattern over time:

- Does the photon actually interact with itself or with the photons fired before/after it?

- What happens we move the whole apparatus sideways each time before emitting another photon? Is there a chance that the photon somehow leaves a trace of itself in space-time and still exists everywhere on its way to the screen? Has this been tested?

 

[Drakkith]

- Does the photon actually interact with itself or with the photons fired before/after it?

The photons fired before the current photon no longer exist, and the ones fired afterwards don't exist yet, so the photon can't interact with them.

- What happens we move the whole apparatus sideways each time before emitting another photon?

Nothing happens. You'll get the same interference pattern if you the entire apparatus around.

Is there a chance that the photon somehow leaves a trace of itself in space-time and still exists everywhere on its way to the screen?

That is extremely unlikely and probably doesn't fit with our current understanding of physics. I don't know of any such way for a photon or any other particle to leave a trace of itself in spacetime.

Has this been tested?

Testing for a "trace" left in spacetime? I doubt anyone has tested specifically for this, but there have been a large number of variations in the experiment over the last 75+ years, so any such trace or deviation from the expected pattern would have almost certainly been noticed.

 

[ElanaC]

Thanks for the reply! :)
I just thought, if quantum entanglement exists regardless of space-time it is not necessary to exist regardless of both. To explain such a behavior (transfer of information successfully) it would be enough to reduce either space or time to one. If we reduce time to one, that would mean it simultaneously manages to exist in all its path at once. If we reduce space to one, well, that should be a wormhole of a kind, then transfer of information about spin and orientation are relevant. Not that I expect to establish some bridge between quantum mechanics and general relativity, but I just wondered if there is a way to conduct an experiment to define which of both (space or time) gets minified to this effect.

 

[Drakkith]

I'm sorry I don't know what you mean by "reducing to one". Please keep in mind that we only discuss mainstream physics here at PF, not personal theories or ideas.

 

[lekh2003]

Is there a chance that the photon somehow leaves a trace of itself in space-time and still exists everywhere on its way to the screen?

There is a simple variation in the experiment which eliminates this possibility.

You're experiment assumes that in a room, there is a double slit and a screen. You then proceed to shoot photons one at a time at the screen through the double slit (say you shoot a thousand photons). You're assumption is that we should still see the interference pattern because the photons are interfering with future and past versions of previous photons.

What if you had 1000 rooms with 1000 double slits and 1000 screens and shot one photon through each double slit and onto the screen? There is no trace of previous or past photons since they are in completely different positions in space time. If you combine all the images from the 1000 screens in one image, you will still see the interference pattern.

Did that help your understanding?

Not that I expect to establish some bridge between quantum mechanics and general relativity, but I just wondered if there is a way to conduct an experiment to define which of both (space or time) gets minified to this effect.

This is somewhat what string theory attempts to do, but you are still far off. However, considering your current understanding of quantum physics, I strongly recommend you continue studying quantum physics before jumping head first into the most pressing question in modern physics.

 

[ElanaC]

Thanks a lot for the reply, lekh2003! I'm not a physicist, I just subscribed to some youtube science channels and I find quantum physics really fascinating, but I had some questions and no one to ask, that's how I searched "physics forums" and landed here. I'm sorry for my lame questions and bad English (I'm not a native speaker). @any moderator out there - feel free to delete this thread.

 

[lekh2003]

No need to delete the thread. You asked a question and it has been answered. More people like you can then get their answers from this thread.

Deleting only happens when you blatantly ignore the rules or if you argued about the rules on the thread.