The quantum-interpretations tag has no wiki summary.
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Shor's algorithm and Bohmian Mechanics
Do quantum computer's tell us anything about the foundations of quantum theory? In particular Shor argued in the famous thread by 't Hooft
Why do people categorically dismiss some simple quantum ...
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Is contextuality required in quantum mechanics?
I still don't really understand what contextuality means in reference to quantum mechanics. If someone could give a clear definition that would be great. It sounds like it means you can't always ...
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Assumptions in Bell's Theorem
It is often Stated that Bell's Theorem is equivalent to the statement: No theory of Local Hidden Variables can reproduce all of the predictions of quantum mechanics. I see nowhere in Bell's Theorem ...
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What counts as a measurement?
In quantum mechanics, an elementary particle does not have a well defined position until a measurement is performed on it (right?). Such a "measurement" is any sort of interaction with other ...
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Spekkens Toy Model, Internal Comonoids
I have been thinking about Spekkens Toy model in terms of interfaces. The Spekkens paper concerns a physics based on only being able to receive answers to half the number of questions necessary to ...
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Quantum Mechanics - Hidden Variables
In Steven Weinberg's Lecture on Quantum Mechanics (p. 342), he writes:
The correlation between the spins of the two particles can be
expressed as the average value of the product of the ...
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Event-by-Event Simulation of Quantum Phenomena
I just recently stumbled over
http://rugth30.phys.rug.nl/dlm/
and
http://www.sbfisica.org.br/bjp/files/v38_26.pdf
As the title suggests these are presentations of mathematical models capable of ...
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383 views
How isolated must a system be for it's wave function to be considered not collapsed?
As an undergrad I was often confused over people's bafflement with Schodinger's cat thought experiment. It seemed obvious to me that the term "observation" referred to the Geiger counter, not the ...
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Can decoherence work when the environment itself is in a superposition without invoking collapse or splitting?
Decoherence is often presented as a program to solve the measurement problem using only the bare bones quantum mechanics framework of a Hilbert space and unitary Schrödinger time evolution. As ...
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Is it possible to reproduce the energy spectrum of quantum chaos using classical cellular automata?
Is it possible to reproduce the energy spectrum of quantum chaos using classical cellular automata? It's hardly impressive to reproduce harmonic oscillators.
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Does it make sense to speak of amplitudes of finite closed boundaries in QFT?
A example of amplitude in Relativistic Quantum Mechanics or specifically in QFT is the amplitude of a field configuration on a space-like hyper-surface of space-time to "lead" to another field ...
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Connection between quantum physics and consciousness
Can someone explain the quantum physics-consciousness connection? In the double slit or quantum eraser experiments, the system behaves as a whole, with some apparent time independent traits. Invoking ...
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Is it possible that QM is just GR?
The more I learn about General Relativity, the more it seems like it isn't fully understood. It seems that before it's full consequences were exhaustively understood, not 10 years after its discovery, ...
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If the multiverse and many-worlds don't exist, how should we interpret probabilities?
If the multiverse of eternal inflation and the many-worlds of quantum mechanics don't exist, how should we interpret the meaning of probabilities? If there is only one copy of the universe out there, ...
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Retrocausal interpretations of quantum mechanics
Can retrocausality resolve the paradoxes of quantum mechanics? The Copenhagen interpretation presumes something has no property until it is measured, but retrocausal interpretations explain that away ...
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Does this new quantum experiment rule out the possibility of a many-worlds interpretation?
This brand new published result (nature):
Experimental non-classicality of an indivisible quantum system by
Radek Lapkiewicz, Peizhe Li, Christoph Schaeff, Nathan K. Langford, Sven ...
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If nothing is “objectively real” prior to “measurement”, what exactly is a “measurement”?
If nothing is "objectively real" prior to "measurement", what exactly is a "measurement"?
Is there any "objective" criteria to demarcate a process as being a "measurement" or not? If "measurements" ...
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How do we show that no hidden variable theories can replace QM?
I've always hit two big stumbling blocks in conceiving of the proof or disproof of hidden variable theories as being even valid idea, let alone an answerable question... I feel I must be ...
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QM: Expectation value of x*p <xp>, how interpret?
$xp$ is not a hermitian operator and hence doesn't represent an observable. Then, how can we interpret the expression
$$
\langle x p \rangle \text{,}
$$
the expectation value of position times ...
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Is quantum entanglement an objective or subjective property?
Imagine the following gedankenexperiment. Observer Alice is right here on Earth. Observer Bob is at say Alpha Centauri. A pair of maximally entangled qubits is formed with one qubit handed over to ...
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What is the physical interpretation of the density matrix in a double continuous basis $|\alpha\rangle$, $|\beta\rangle$?
(a) Any textbook gives the interpretation of the density matrix in a single continuous basis $|\alpha\rangle$:
The diagonal elements $\rho(\alpha, \alpha) = \langle \alpha |\hat{\rho}| \alpha ...
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Can the Heisenberg interpretation or path integrals apply to open quantum systems?
It has been claimed by some people that Schrödinger's picture is more misleading compared to the Heisenberg principle or path integrals, and that we would be better off abandoning the ...
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Wigner's friend and intersubjectivity in quantum mechanics
Suppose there's a radioactive material and a 1/2 quantum probability of detecting it by a Geiger counter. This puts the system in a superposition. Also suppose you are in the same room, and the walls ...
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Motivation for Wigner Phase Space Distribution
Most sources say that Wigner distribution acts like a joint phase-space distribution in quantum mechanics and this is justified by the formula
...
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Weak measurements rule out Many Worlds Interpretation?
I came across a paper that claims to prove that the Many Worlds interpretation is invalid by applying weak measurements.
The paper can be found here: ...
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Interpretation of $e|\psi|^2$ as electron density
In solid state physics the electron density is often equated to $e|\psi|^2$. However, the Sakurai says (Chapter 2.4, Interpretation of the Wave Function, p. 101) that adopting such a view leads "to ...
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Many-worlds: how often is the split how many are the universes? (And how do you model this mathematically.)
When I read descriptions of the many-worlds interpretation of quantum mechanics, they say things like "every possible outcome of every event defines or exists in its own history or world", but is this ...
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Does the Hilbert space of the universe have to be infinite dimensional to make sense of quantum mechanics?
Does the Hilbert space of the universe have to be infinite dimensional to make sense of quantum mechanics? Otherwise, decoherence can never become exact. Does interpreting quantum mechanics require ...
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Are quantum mechanics and determinism actually irreconcilable? [closed]
As a preface, I am not a physicist. I'm simply interested in abstract physics and fundamental principles of the universe and such. As such, if you can provide an answer for the layman (as ...
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Question about Wigner's friend
The Wigner's friend thought experiment can be used to understand non-realism in quantum mechanics. For anyone not familiar, the thought experiment involves two researchers observing an experiment at ...
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320 views
Bohmian loophole in PBR-like theorems
I'm reviving and expanding this question, because of the new paper today, by Aaronson et al. The more general question is:
How does quantum-potential Bohmian mechanics relate to no-go theorems for ...
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Does quantum fingerprinting really argue for the exponential size of wavefunctions?
Does quantum fingerprinting really argue for the exponential size of wavefunctions? Quantum fingerprinting is the idea that an exponentially long classical string can be encoded in a linear number of ...
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952 views
What is the meaning of Wheeler's delayed choice experiment?
Wheeler's delayed choice experiment is a variant of the classic double slit experiment for photons in which the detecting screen may or may not be removed after the photons had passed through the ...
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Determinism, classical probabilities, and/or quantum mechanics?
[I]f you want a universe with certain very generic properties, you seem forced to one of three choices: (1) determinism, (2) classical probabilities, or (3) quantum mechanics. [My emphasis.]
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Does the extended probability ensemble interpretation of quantum mechanics make any sense?
Gell-Mann and Hartle came up with the extended probability ensemble interpretation over here.
Basically, they extended probability theory to include real numbers which may be negative or greater than ...
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What's the worst thing about the tomographic approach to QM?
I saw a paper on arXiv that referenced this approach to an ontology of QM:
Phys.Lett. A213 (1996) 1, S. Mancini, V. I. Man'ko, P.Tombesi Symplectic tomography as classical approach to quantum ...
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How can new interpretations of QM help?
There is some current work on interpretations of quantum mechanics. How do you think can interesting results in that area help physics? Can it change quantum physics or make it easier?
Which ...
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Which physically acceptable quantum interpretations do not require the existence of any observer at all?
Some interpretations of quantum mechanics — like the Copenhagen interpretation in particular — require the existence of an observer. The role of the observer is a bit mysterious. After ...
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Why should the observed probability distributions in quantum mechanics always align with the pointer basis of decoherence?
It has always been claimed decoherence solves the problem of the preferred-basis for observed probability distributions, but why should this be the case? If there is only one world, and there are ...
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Is the wave function objective or subjective?
Here is a question I am curious about.
Is the wave function objective or subjective, or is such a question meaningless?
Conventionally, subjectivity is as follows: if a quantity is subjective then ...
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Interpretation of de Broglie wave
Until what point can the de Broglie wave be thought as a real wave?
I mean, is it made of something?
What amplitude does it have? Is it a sine wave?
How can it be related to the wavefunction of the ...
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Is it possible to determine the state or values of something without measuring it
To give context to this question, I am currently looking into non-locality / hidden variables / Bell's Theorem, EPR / etc.
I've noticed the assertion that the values / state of something when ...
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Defining Measurement in Quantum Mechanics
I should begin by saying that I am a total newbie when it comes to Quantum Mechanics. Therefore my question might sound metaphysical to people who know their stuff. So please forgive.
What I am ...
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Is there a manifestly Lorentz invariant formulation of the many worlds interpretation?
First, I give an absurd example.
A conscious observer lives on Earth at time t. A light-year away, at a space-like separation, a nuclear bomb chain reaction goes off. A nuclear bomb chain reaction is ...
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What does the Copenhagen interpretation say about the position of a particle before measurement?
Suppose there is a particle in space. When we measure the position of that particle, we get a particular value with a probability that can be calculated from the wave function. But, according to the ...
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If the moon is not there when no one is looking, how does the moon know how to stay in orbit between observations?
Quantum Copenhagenists will tell you if there is a stop sign, it only manifests itself by the act of observation. When no one is looking, there is nothing there. This is like the cognitive process of ...
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316 views
Is there any quantum interpretation which isn't “crazy” at all? [closed]
Is there any quantum interpretation which isn't "crazy" at all? Exponentially many parallel worlds in MWI, superdeterministic conspiracies, and/or nonlocality in hidden variables, idealism and the ...
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What is the difference between parallel universe and multiverse?
What is the difference between parallel universe and multiverse? Is it parallel universe or universes?
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M-theory and many-worlds interpretation
I am getting some confusion on whether M-theory accepts many-worlds interpretation. Can anyone show me the reasons or rebuttals for the possibility of the many-worlds interpretation in M-theory? ...
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Are Everettian branchings global or local?
Everett's theory of quantum mechanics is about the wavefunction of the whole universe holistically. If a branching occurs very far away at the Andromeda galaxy, do I also branch? Are branchings global ...
