Questions tagged [wavefunction-collapse]
Wavefunction collapse amounts to the apparent reduction of a wavefunction consisting of a superposition of several eigenstates to a single eigenstate (by "observation"). It underlies measurement in quantum mechanics and connects the wave function with classical observables, in a thermodynamically irreversible interaction with a classical environment, normally disfavoring future QM interference.
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To what degree should macroscopic objects be in superposition of position states according to standard quantum theory?
In this review article on objective collapse theories, which is also linked from this Phys.SE post, at least in the part I've read so far, a deal of fuss seems to be made about the fact that we don't ...
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Two measurements on entangled system: does it make sense to say that one observer collapses the state? [duplicate]
Lets say there are two entangled Qubits A, B, very far away from each other and described by the state $|\Psi\rangle = |++\rangle + |--\rangle$ In a reference system S, A measures + and one hour ...
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Regaining wave nature after partial interaction in double-slit experiment [closed]
In the standard double-slit experiment, placing a detector at one slit causes the wavefunction to collapse, preventing an interference pattern. I am exploring whether wavefunction recovery is possible ...
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Can the observer collapse the quantum superposition without physically measuring the system?
I've been thinking about the quantum measurement problem and have come up with a perspective on the observer's role in collapsing a quantum superposition. Traditionally, it's believed that an observer ...
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Can collapse of wave function change energy of the system?
I am trying to understand basics of quantum mechanics. I apologize for my obtuse thinking and tedious notation. Suppose that I have some quantum mechanical system with Hamiltonian $H$. Assume that ...
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Existence of Momentum Eigenstates [duplicate]
I have been going through Shankar's QM book. In Chapter 4 under the topic of "How to Test Quantum Theory", he proposed that first of all we need to have a well known quantum state and for ...
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How is it proved that the collapse of the quantum wavefunction is the only source of nondeterminism?
I have heard the following claims: The collapse of the quantum wavefunction can be shown mathematically to be truly nondeterministic. We know of no other physical phenomenon that is truly ...
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Is the "wavefunction collapse" interpretation consistent with relativity?
This can be viewed as a follow up to this/this questions about an apparent inconsistency between the notion of wavefunction collapse and relativity. The setup is simple: two entangled systems are ...
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How would you derive the Copenhagen interpretation rules from the many-worlds theory?
I have a real problem with understanding this one. Suppose you are taught in some school, without access to experiments, just theory, the many-worlds interpretation of physics. So that's all you have, ...
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Does the wave function of a group of particles collapse upon a collective measurement?
Say we have 10 electrons in a box. If we measure the spin of an individual electron along some axis, we find it to be spin up or down, but not in between. But what if we measure the combined spin ...
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Is projective evolution an intrinsic part of quantum mechanics? [closed]
If you want to study 1 electron, it is described by wavefunction $\psi(x, y, z, t)$ and its evolution is dictated by Schrodinger equation. If you want to study its interaction with another electron, ...
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Single particle measurement in entangled states [closed]
There is a system with two particles in a state given by the wave function $F(x_1,x_2)$. What does it mean to make a measurement on one of the particles? This is not defined among the axioms of ...
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Wave function collapse at particle detection [closed]
There is a particle source, which emits particles (e.g. radioactive decay). It is supposed that the wave function is spherical. The process is isotropic. If I put two detectors (A and B) at distance R ...
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What is currently the currently understood relationship between classical and quantum world?
Which of these is understood to be the relationship between classical and quantum mechanics? Or is it a mixture of these, or something else entirely? The classical world comprises of measurement ...
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Solution to the measurement problem - explanation
Has the measurement problem been resolved? Could someone explain the current state-of-the-art understanding of why deterministic evolution results in a random measurement outcome? Is there a model ...
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