Interference between different kinds of particles

  • Context: Graduate 
  • Thread starter Thread starter id the sloth
  • Start date Start date
  • Tags Tags
    Interference Particles
Click For Summary

Discussion Overview

The discussion revolves around the possibility of interference between different types of particles, specifically focusing on whether an electron and a proton can interfere with one another, and more generally, if different kinds of particles can exhibit interference effects. The conversation includes theoretical considerations, implications of wave functions, and entanglement, with references to particle decay and experimental setups.

Discussion Character

  • Debate/contested
  • Conceptual clarification
  • Exploratory

Main Points Raised

  • Some participants propose that only identical particles can interfere, as interference requires the ability to add amplitudes.
  • Others argue that while different particles cannot interfere, their wave functions can influence each other, particularly in entangled states.
  • A participant suggests that a neutron decaying into a proton, electron, and neutrino could theoretically create an interference pattern, depending on the phase of the resulting waves.
  • Another participant questions the setup of interference after decay, stating that once a neutron decays, the resulting particles do not interfere with each other.
  • Some participants discuss the modeling of radioactive particles, suggesting that a physical neutron can be viewed as a combination of its mass states and decay products.
  • Concerns are raised about the assumptions made regarding the behavior of particles post-decay and the nature of interference patterns in experimental contexts.

Areas of Agreement / Disagreement

Participants express differing views on the nature of interference between different types of particles, with no consensus reached. Some maintain that interference is limited to identical particles, while others explore the implications of entanglement and decay.

Contextual Notes

Limitations include assumptions about particle interactions, the definition of interference, and the conditions under which wave functions may influence one another. The discussion also highlights the complexity of modeling particle decay and the resulting states.

id the sloth
Messages
67
Reaction score
0
I have only an completed one course on quantum mechanics so please excuse me if this seems rudimentary.

In my course we only dealt with electrons and their interference with one another. Is it possible for an electron and a proton to interfere with one another? Or more generally, can different types of particles interfere with each other?
 
Physics news on Phys.org
No. Only identical particles can interfere - you have to be able to add amplitudes.
 
Okay. But the wave functions can still influence each other right? If I were to shoot a proton and neutron at each other and measured the momentum on the proton, assuming I knew the initial momentums, I would be able to figure out the momentum of the neutron in theory. Which means that the wave functions are in an entangled state correct?
 
id the sloth said:
Okay. But the wave functions can still influence each other right? If I were to shoot a proton and neutron at each other and measured the momentum on the proton, assuming I knew the initial momentums, I would be able to figure out the momentum of the neutron in theory. Which means that the wave functions are in an entangled state correct?

Yes, that's of course correct. If there is an interaction between particles then that will obviously infuence the time evolution of their wave functions.
 
Sweet, just making sure. Thanks!
 
No. Only identical particles can interfere - you have to be able to add amplitudes.
We can kinda have interference pattern of different particles, at least in theory.

First we get a particle that decays into few others. Say, a neutron decaying into proton, electron and a neutrino. We shoot this neutron and wait. We can say that it is composed of 3 waves of different speeds. When they all are in phase, we have high probability of detecting a neutron. When the time passes and the 3 waves phase out, we have high probability of detecting proton, electron and neutrino. If we wait a bit longer, the waves will eventually reach the same phase again and create a neutron. I'm assuming that all particles move only in one dimension, but it's only a theory.

If we place detectors along the path of this particle, we will get high probability of detecting a neutron at some places and high probability of proton, electron and neutrino at other places.

Even more, if we did a double-slit experiment with a neutron, we would get a sophisticated interference pattern of detecting neutrons, protons, electrons, neutrinos or no particle at all, with some probabilities. This would have to be huge experiment to let the neutron decay in the process. I make an assumption that 3 particles after neutron decay do not move relative to each other, which is not true in nature, but I hope you get the idea.

In general, any two entangled particles of any kind would give something like an interference pattern in the double-slit experiment.
 
That is really is interesting. Is that how you model radioactive particles? As the sum of the wave functions of the decay products?
 
Particles only interfere with themselves, not with other particles.

ie a single photon, electron, elephant can only interfere with itself, not with another photon, electron, elephant.

So obviously a particle could not interfere with a "different kind of particle"
 
Particles only interfere with themselves, not with other particles.
Unless they are entangled.

That is really is interesting. Is that how you model radioactive particles? As the sum of the wave functions of the decay products?
Not quite. Rather, you can say that "physical" neutron is a sum of two waves: "ideal" neutron and (proton, electron, neutrino) triple. These 2 waves happen to be the mass states. Real physical neutron is not the mass state. If the decay products didn't interact except turning into a neutron again, and didn't scatter immediately after decay, then you would get something similar to neutrino oscillations.
 
  • #10
unusualname said:
Particles only interfere with themselves, not with other particles.

ie a single photon, electron, elephant can only interfere with itself, not with another photon, electron, elephant.

So obviously a particle could not interfere with a "different kind of particle"

In my chem class, the taught us that bonds could be explained as the shared electrons constructively interfering with each other to minimize energy though
 
  • #11
haael said:
Not quite. Rather, you can say that "physical" neutron is a sum of two waves: "ideal" neutron and (proton, electron, neutrino) triple. These 2 waves happen to be the mass states. Real physical neutron is not the mass state. If the decay products didn't interact except turning into a neutron again, and didn't scatter immediately after decay, then you would get something similar to neutrino oscillations.

What happens to the "ideal" neutron wave when the "physical" neutron decays?
 
  • #12
haael said:
We can kinda have interference pattern of different particles, at least in theory.

I don't understand that setup. Once the neutron decays, you have a proton and electron and neutrino propagating more or less freely. Before it decays you have none of these, and justa neutron propagating freely. Nothing is interfering with anything else.
 
  • #13
id the sloth said:
What happens to the "ideal" neutron wave when the "physical" neutron decays?

There is no more neutron wave. Once the Neutron decays it is gone.
 
  • #14
haael said:
Unless they are entangled.

Entangled particles still don't interfere with each other.


Not quite. Rather, you can say that "physical" neutron is a sum of two waves: "ideal" neutron and (proton, electron, neutrino) triple. These 2 waves happen to be the mass states. Real physical neutron is not the mass state. If the decay products didn't interact except turning into a neutron again, and didn't scatter immediately after decay, then you would get something similar to neutrino oscillations.

I've never heard of this before and it sounds pretty iffy to me. Got a reference?

Even more, if we did a double-slit experiment with a neutron, we would get a sophisticated interference pattern of detecting neutrons, protons, electrons, neutrinos or no particle at all, with some probabilities. This would have to be huge experiment to let the neutron decay in the process. I make an assumption that 3 particles after neutron decay do not move relative to each other, which is not true in nature, but I hope you get the idea.

This doesn't really make sense to me. If you let the neutron decay you would get detections and interference of protons, electrons, and nuetrinos but no neutrons, as they have decayed. (Or rather most of them depending on the amount of time between emission and detection)
 

Similar threads

Undergrad Does a qubit break interference in the double slit experiment?
  • · Replies 10 ·
Replies
10
Views
2K
Undergrad Is quantum interference an instantaneous consequence of superposition ?
  • · Replies 12 ·
Replies
12
Views
2K
Undergrad Double slit experiment with observer
  • · Replies 14 ·
Replies
14
Views
4K
Undergrad Why do orthogonal polarizers at slits eliminate interference pattern?
  • · Replies 28 ·
Replies
28
Views
3K
Undergrad Have You Heard of the SEW Experiment? Thoughts?
  • · Replies 3 ·
Replies
3
Views
3K
Undergrad "Wave-particle duality" and double-slit experiment
  • · Replies 36 ·
2
Replies
36
Views
9K
Undergrad Photon interference and beamforming
  • · Replies 64 ·
3
Replies
64
Views
6K
Undergrad Double Slit Interference Question
  • · Replies 19 ·
Replies
19
Views
3K
Undergrad What is the true nature of microscopic particles when not interacting?
  • · Replies 4 ·
Replies
4
Views
2K
Graduate The different interference patterns in the double-slit experiment
  • · Replies 1 ·
Replies
1
Views
2K