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2 votes
0 answers
50 views

Is it possible that a macroscopic object tends to a separable state without the need for objective collapse?

For a multi-particle system, superposition is in some sense equivalent to entanglement; with the Dirac field being treated as classical under second quantization, for example, we could at least argue ...
3 votes
3 answers
221 views

Was Einstein "spooky action at a distance" about entanglement or about wave function collapse?

I've been watching Sabine's videos and this is my understanding: There is no "spooky action at a distance" based simply on entanglement. Entanglement is a correlation. There is no ...
0 votes
4 answers
331 views

Is signal photon independent of idler photon in Delayed Choice Quantum Eraser?

--Diagram from Wikipedia of the experiment of Kim et al. (1999) Original research paper: A Delayed Choice Quantum Eraser I want to know whether the landing position of the signal photon (photon that ...
6 votes
3 answers
260 views

Is wavefunction collapse “global”?

I have the feeling that the premises of this question may not be coherent (so to speak), but here goes: Suppose we have a system $X$ in a quantum superposition between states $0$ and $1$, say, with ...
-1 votes
2 answers
111 views

Simultaneous measurements of two entangled particles [duplicate]

Experimental evidence reject the local hidden variable theory, so let's say quantum mechanics is right and the wave function does instantaneously collapse upon measurement. Suppose we have two ...
19 votes
1 answer
7k views

Is my interpretation of the underlying idea behind this 2022 Nobel Prize story “How physicists proved the universe isn’t real” more or less accurate?

I’m not very good at math but I frequently watch PBS Spacetime on YouTube to try to satisfy my curiosity about physics despite that. In a recent video by Dr Ben Miles titled “How Physicists Proved the ...
0 votes
1 answer
119 views

Postulate of wave function collapse and entanglement

Can we say that a measurement on a system of $k$ entangled particles is the cause of the collapse of the wave function into $k$th states simultaneously?
0 votes
1 answer
73 views

Quantum entanglement

Suppose we have two particles with entangled eigenfunctions. Let's say they are in two different regions of space, with different local Hamiltonians. Now we measure one of them, therefore the other. ...
1 vote
0 answers
45 views

Quantum entanglement information through time of collapse

(I've tried my best to find an existing question that asks this question exactly) From what I understand, given two entangled particles, one held by Alice and one by Bob, when a measurement is done by ...
1 vote
1 answer
207 views

Will the Hilbert space get expanded when measuring the entangled state?

If I have two electrons that are indistinguishable, as I understand, they are entangled. And the Hilbert space that describes the behavior of this pair of electrons is a subspace of the Tensor product ...
2 votes
0 answers
115 views

Have objective collapse theories been ruled out by recent experiments?

Have objective collapse theories been ruled out by recent experiments, such as the entanglement of macroscopic objects? (vibrating drumheads)
0 votes
0 answers
45 views

Has there been experimental evidence that entangled state collapses simultaneously?

If we observe the observable of one particle among two particles which are entangled each other and separated far away, we can determine the value of the other particle’s same observable from the ...
3 votes
4 answers
4k views

Entanglement and the double slit experiment

Is the double slit experiment an example of entanglement when it seems as if the photon is going through both slits? Or put another way, is it at this stage when we attempt measurement we see a photon ...
6 votes
3 answers
335 views

Are combined fermion wavefunctions still antisymmetric after wavefunction collapse?

If we have two electrons in a state $|\psi\rangle=\frac{1}{\sqrt2}[|\uparrow\downarrow\rangle+|\downarrow\uparrow\rangle]$ and we measure the spin of the first electron to be up, does the wavefunction ...
0 votes
1 answer
111 views

Detecting collapse using single slit

A collapsed state should act like a particle and a non-collapsed like a wave. Is this statement true? So if you had a single slit and detectors behind it off to the sides... The collapsed state should ...

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