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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Objective collapses, stochasticity, conservation of energy and signalling
While reading about general objective collapse theories (not being bound to a specific models) I came across the following:
Any nonlinear and deterministic modification to Schrodinger equation ...
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How do atoms and molecules form structure without quantum measurements on position?
As stated in the title - quarks and gluons find each other, protons bind to neutrons, and electrons are captured to form stable atoms. These atoms then can form complex molecules with robust 3D ...
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Range of parameters in objective collapse models-Ghirardi vs. Adler
I'm trying to summarize the state of the art of objective collapse models-in the nearby future I will post some more questions about them but let me start with the following, which I hope is precise ...
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How does applying an observable collapse a quantum state mathematically?
Say that $\hat E$ is an observable operator.
We can expand out $|\Psi\rangle$ as $$|\Psi\rangle=
c_1|E_1\rangle+c_2|E_2\rangle+c_3|E_3\rangle ...$$
Since $\hat E$ is a linear operator, $$\hat E|\Psi\...
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Wavefunction Collapse with imperfect information
Consider the following scenario:
You have a particle detector that clicks when a quantum particle is near its vicinity. This is a "position measurement." Therefore, under the Copenhagen ...
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Collapse of wave function of large objects [duplicate]
When we measure the position of a particle,it collapses to a new wavefunction which is a dirac delta function.It's probability density spikes at a particular position value.So when we measure its ...
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Question on Wave Function Collapse in Quantum Experiments [duplicate]
Is it really the act of conscious observation that collapses the wave function, or could it be the presence of additional measurement apparatus eliminates the interference pattern independent of a ...
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Why does the wavefunction collapse after no detection?
In a beam splitter experiment with a single photon, if I place a detector on one path and after some time it never clicks, why does the wavefunction still collapse to the other path even though I ...
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What happen with wavefunction immediately after a measurement?
One of the postulates of quantum mechanics, introduced by Dirac, says that immediately after a measurement of an observable $\hat A$ the wavefunction abruptly becomes an eigenfunction of $\hat A$. In ...
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When does a transition collapse to the final state?
I did my PhD research on device physics of optoelectronic devices. We take the square of
$\langle f| H_{int} |i\rangle $ as the photon absorption probability or the theoretical efficiency of a ...
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Wave Function and Measurement (Landau-Lifschitz Volume 3)
I believe Landau is trying to motivate the collapse of a wavefunction. However, there are some parts which are confusing.
He claims that the apparatus is in an initial state $\Phi_0(\xi)$ while the ...
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Is the collapse of the wavefunction really part of the quantum theory?
The collapse of the wavefunction by comparing it with the Schrodinger equations has some differences: it is higly non-linear while the Schrodinger equation is linear, it is non-local as proven by Bell'...
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Doesn't the Many Worlds Interpretation simply move the collapse of the wave-function to the brain/consciousness? [closed]
As far as I understand as a layman (and forgive me if I say anything wrong, I am merely stating my current understanding), quantum mechanics predicts outcomes based on a wave function, which is a ...
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Objective collapse of wavefunction energy equivalence
I was introduced to the objective wavefunction collapse by dr.Sean Caroll.
He explains that objective wavefunction collapse theories say that after some finite time the wavefunction of a electron ...
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Quantum measurement and perturbation [duplicate]
In quantum mechanics it is said that a measurement collapses the wave function while perturbation changes the hamiltonian but how a system knows if my interaction with it is just a perturbation or a ...
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