Does the double slit experiment show waves collapse when observed?

[Sciencelad2798]

TL;DR

Does the wavefunction collapse when looked at?

Do wavefunctions collapse when looked at? Or does observe mean something else?

https://www.nature.com/articles/d41586-018-05892-6
This article is where my information is from, physicists talking about how our mind causes the collapse.

 

[DennisN]

Summary:: Does the wavefunction collapse when looked at?

Do wavefunctions collapse when looked at? Or does observe mean something else?

"Observation" in quantum mechanics is a rather nonspecific word which means measurement and/or interaction with a measurement device or some other system. That is, the word observation does not imply human observation.

The question of wave function collapse is an interpretational issue. Some interpretations of Quantum Mechanics have wave function collapse, others don't. The "Consciousness causes collapse" interpretation (von Neumann–Wigner interpretation) is only one interpretation of many.

 

[Sciencelad2798]

"Observation" in quantum mechanics is a rather nonspecific word which means measurement and/or interaction with a measurement device or some other system. That is, the word observation does not imply human observation.

The question of wave function collapse is an interpretational issue. Some interpretations of Quantum Mechanics have wave function collapse, others don't. The "Consciousness causes collapse" interpretation (von Neumann–Wigner interpretation) is only one interpretation of many.

Ohhhhh thank you. But how does measurement cause this collapse?

 

[PeroK]

Summary:: Does the wavefunction collapse when looked at?

Do wavefunctions collapse when looked at? Or does observe mean something else?

https://www.nature.com/articles/d41586-018-05892-6
This article is where my information is from, physicists talking about how our mind causes the collapse.

That article is not a source from which you can learn QM. It's pure journalism.

 

[DennisN]

But how does measurement cause this collapse?

Wave function collapse is not universally embraced as actually happening. As I said, different interpretations have different views on this. How/why we get single outcomes in measurements is a million dollar question which has been heavily debated throughout the years. Two concepts I suggest searching for and reading about is "measurement problem in quantum mechanics" and also "quantum decoherence".

 

[PeterDonis]

Do wavefunctions collapse when looked at?

It depends on which interpretation of QM you are using. So while you have posted this question in the right forum (the QM interpretations forum), that very fact should alert you that there is not one "right" answer to your question.

 

[EPR]

This article is where my information is from, physicists talking about how our mind causes the collapse.

Metaphysical claims that one way or another posit or hypothesize that the world could be or is virtual cannot be falsified and thus do not dwell in the realm of science.

 

[kurt101]

It might be worth watching Sabine Hossenfelder's explanation of the double slit experiment here:


On the slit where you don't detect the particle, there is still a wave that disperses just like the one that is part of the interference. Given a pilot wave interpretation, unlike the EPR experiment, I don't see any evidence of anything collapsing.

How does the pilot wave interpretation describe what happens in the EPR and double slit experiment in terms of collapse? Does it describe either the particle or the pilot wave as collapsing in either one of these experiments?

 

[PeterDonis]

How does the pilot wave interpretation describe what happens in the EPR and double slit experiment in terms of collapse?

It doesn't; there is no collapse in the pilot wave interpretation.

 

[Sciencelad2798]

It doesn't; there is no collapse in the pilot wave interpretation.

I had this question about the double slit theory i was hoping you might be able to answer: if we fire single particles at the slits surely we aim them at the central block rather than at one slit or other right? If so then the expectation should be no pattern at all as should hit the central block. However actually goes through one or other slit, this must mean the single particle is bending its path once decides which slit to go through. Surely it is just as amazing that the particle decides to veer off a straight line as the overall result of the pattern made?

 

[PeterDonis]

if we fire single particles at the slits surely we aim them at the central block rather than at one slit or other right?

We aren't aiming the particles precisely enough for that. The whole point of the double slit experiment is that, while the direction the particles are traveling is very well controlled (they are all moving towards the barrier with the slits in it), the position of the particles is not; the uncertainty in the particles' position is significantly larger than the spacing between the slits. (The tradeoff involved here is unavoidable because of the uncertainty principle.)