All Questions
Tagged with quantum-interpretationsquantum-mechanics
914 questions
-4votes
0answers
60views
I’m exploring a collapse model where mass induces a geometric-coherence tension, predicting a collapse probability [closed]
I’m exploring a collapse model where a nearby mass induces a “geometric-coherence tension” in the environment, giving rise to a position-dependent collapse probability P(r,m) = 1 - exp(-α · m / r^2) I’...
2votes
2answers
106views
How can the "true" density matrix for any quantum system evolve towards a diagonal form?
Regardless of how many particles we have, isn't it still the case that the combined system has a state which is a single vector in the (multi-particle) Hilbert space? Even after time-evolution, it is ...
- 2,755
0votes
2answers
70views
The No-Communication Theorem and QM Interpretations
In popular literature, the no-communication theorem is sometimes described as follows: when Alice tries to send a message to Bob using quantum entanglement, this message is always multiplied by random ...
- 215
0votes
0answers
58views
How does Bohmian mechanics change the analysis of the standard Bell type Alice/Bob experiment? [duplicate]
So I'm looking for some clarification on this. This is how I understand Bohmian mechanics. Particles have definite trajectories. The trajectory is guided by the wave-function. How does Bohmian ...
- 1,244
4votes
2answers
384views
Clarification regarding argument in EPR paper
I read through the original EPR paper recently and ran into some confusion regarding the central argument. As I understand it, the authors assert the following two definitions: Assumption 1: A ...
0votes
0answers
52views
Why randomness taking a specific outcome at that time? [duplicate]
Im a 16 year old and this question stuck in my mind. I cant find apt answer. Imagine we tossed a coin, we have 50-50% chance to get heads or tails. We say its random but truly we can predict the ...
5votes
3answers
613views
How can we be sure our ensembles of particles are prepared similarly in quantum mechanics?
A fundamental presupposition in quantum mechanics is that we are able to prepare ensembles of identical systems, sometimes called "similarly prepared systems". But how can we know whether ...
- 1,351
2votes
2answers
104views
In the Many-Worlds Interpretation, how many degrees of freedom does the universe have? [closed]
I was wondering if it is possible to have a ballpark estimate, or at least a plausible minimum or maximum of the number of possible eigenstates (or is it eigenvalues?) that the universal wavefunction ...
- 711
-3votes
1answer
126views
Is the electron ubiquitous? [duplicate]
Quantum mechanics postulates that an electron is in many places at the same time. Can't we set up experiments to see if it exerts its electromagnetic influence in many places at the same time? (Or ...
4votes
7answers
2kviews
How much can an observer know about its own quantum state?
Let me state my background: I am familiar with the usual formalism of QM, of how measurements are modeled, measurement problem, decoherence, etc. In thinking about the process of measurement, I was ...
- 85
4votes
2answers
153views
Has anyone constructed an explicit hidden-variable theory that reproduces the predictions of quantum mechanics for two separated qubits?
Consider the Hilbert space $$\mathcal{H} = \mathrm{span}\left( \{ |0\rangle\ |0\rangle, |0\rangle\ |1\rangle, |1\rangle\ |0\rangle, |1\rangle\ |1\rangle \} \right) \cong \mathbb{C}^4$$ of (pure) ...
- 50.2k
-2votes
1answer
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If the entire universe is governed by QM, and only by QM, would that imply MWI? [closed]
Edit: Based on @WillO's very relevant comment, I want to clarify what I mean by "fully governed by QM" - it means governed only by the laws of quantum mechanics, as opposed to classical ...
- 711
1vote
6answers
286views
Can a quantum measurement be made undone?
Can a quantum measurement be made undone, so that the original superposition reappears? Let me illustrate my question with an example. Consider the Schrödingers cat thought experiment, in which the ...
- 1,609
5votes
5answers
1kviews
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 ...
- 2,255
-2votes
1answer
103views
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, ...
