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Is quantum physics weirdness caused by our imperfect measuring tools and senses? [duplicate]

The more I learn about quantum physics the more it seems to me that it is not the "real" world that is weird but it's that quantum physics theory itself has inbuilt randomness that's caused by the way ...
2
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2answers
90 views

Flipping a coin with same initial conditions

Today, in my physics class my teacher was talking about how we can never predict the outcome of a coin flip. So I thought: Will the outcome of a coin flip be the same if we do not change the initial ...
2
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1answer
89 views

Quantum Mechanics - How do we know that the observed locations of electrons are random? [duplicate]

How do we know that the observed location of a electron (or any quantum object) is purely random (there is no way to predict it) within the probability-function instead of normal randomness (we don't ...
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0answers
73 views

Is the “probabilistic nature of quantum mechanics” and quantum randomness the same?

Digital Physics are a branch of hypotheses about the fundamental physics of our universe. They basically describe the universe as an analogy to a computer and defend that everything in the universe is ...
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2answers
118 views

If the universe is random, why does it contain structure? [closed]

Ive read that the scientific community agrees on that the universe works in a non deterministic way. However, because we have some kind of structure in the universe I assume (from a super novice ...
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1answer
159 views

Why don't physicists interpret randomness in quantum mechanics as ignorance or limitations in our knowledge?

As the title says: why don't physicists interpret randomness in quantum mechanics as ignorance or limitations in our knowledge? Why is the randomness in quantum mechanics equations not added to the ...
0
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1answer
51 views

Gaining intuition about summing over random basis vectors in random matrix theory

I'm currently reading the following reference on eigenstate thermalization and chaos in quantum mechanics: https://arxiv.org/abs/1509.06411 I'm confused by a derivation that I think is very important ...
0
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2answers
213 views

Does quantum randomness exist? [duplicate]

I just want to know if the quantum world is random. Or if the randomness is fully explained by measurement error. Or if it is just semantic. The previous questions are open to interpretation and do ...
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2answers
152 views

Is Quantum Mechanics Compatible with Conservation of Information?

What is exactly the law of conservation of information? In quantum mechanics we have truly random outcomes in experiments, but doesn't this randomness mean that new information is produced and the law ...
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1answer
84 views

What do physicists mean when they say QM proves randomness?

Some physicists like Michio Kaku has said that the physics has proven randomness. Even some of my friends(they're not physicists) cite the Delayed Choice Quantum Eraser experiment and entanglement to ...
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1answer
67 views

Randomness - Quantum Mechanics

If there is pure probabilistic randomness for quantum particles, why isn't this randomness seen in macroscopic objects too, after all they are made up of quantum particles? Why and How does this ...
-2
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1answer
128 views

Could the apparent non-determinism of Quantum Mechanics be explained with a universal pseudo-random number generator? [closed]

As a thought experiment, would it be logically plausible to claim that the apparent randomness of Quantum Mechanics could be explained by the existence of a universal and deterministic pseudo-random ...
24
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9answers
6k views

What exactly is deterministic in Schrödinger's equation?

I have read the following on Wikipedia but I can't understand it: In quantum mechanics, the Schrödinger equation, which describes the continuous time evolution of a system's wave function, is ...
-2
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3answers
79 views

Simulation of multi-particle systems, randomness and chaos

The answer https://physics.stackexchange.com/a/10441/50677 for #2 (chaotic randomness) claims that the absolute knowledge (whatever that would be) of starting conditions were sufficient for a perfect ...
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0answers
84 views

Interpretation of quantum superposition and classical Brownian motion

In the standard, Copenhagen interpretation of quantum mechanics, the usual ontology assigned to the phenomenon that repeated measurements of a quantum mechanical observable yielding different results ...
3
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3answers
156 views

How can we certify that the randomness in the measurement outcomes is not due to randomness in the state preparation?

According to the theory of quantum mechanics, if a spin state is prepared along axis "x", and then measured along axis "z", then the result of the spin projection is probabilistic: half of the times ...
4
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3answers
342 views

How do we know that certain quantum effects are random?

I was looking at a website that claims to generate random numbers from observation of quantum effects. This lead me to question how we know that the numbers are truly random. When we observe a ...
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3answers
305 views

Randomness of photon's spontaneous emission

I'd like to understand why the phase and the direction of a photon spontaneously emitted is random. Is there a "mathematical" rigorous proof of its randomness? I searched for a proof but couldn't find ...
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2answers
423 views

Randomness in Quantum Mechanics

Is the quantum world really random?How can one be sure that there are no variables that can actually predict the outcome like they do in Newtonian physics?
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0answers
58 views

Prove that the randomness of the spins of entangled quantum particles is not due to periodic factors?

I just learnt about entangled particles in a lecture today. According to the theory, the probability of the spin of an entangled particle is 50/50 (spin up or down), and is only determined when ...
3
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3answers
892 views

Is quantum mechanics truly probabilistic?

Probability arises inherently from a lack of information. For example, if I were to take a ball out of a bag with 3 yellow and 2 white balls, I would have a 0.6 probability of getting a yellow and a 0....
0
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1answer
158 views

Is there a consensus about the trueness of the randomness in QM? [duplicate]

I personally believe that there is a very strong case in favor of true randomness in QM but not being a physicist I would like to know from experts if there is a consensus about this. @John Rennie: ...
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0answers
23 views

Is it possible to compute the kubo conductivity of bosons in disorder via mean-field theory?

The kubo conductivity is computed essentially from the current-current correlation function. This works fine when there is no or a periodic potential, as there are a number of ways that can be found ...
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4answers
637 views

Is the quantum world affected by the law of causality, or it is just really random? [closed]

If the quantum world is really random why a random quantum event 'e' happend in the way 'a' and not in the way 'b' . what caused that ?
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2answers
181 views

Is there even something like true randomness?

So a few months ago a research team did the following experiment: https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.118.060401 They shot lasers at certain detectors trying to detect the spin ...
2
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1answer
54 views

Does quantum randomness allow extreme deviations like Gaussian randomness does?

{ I am explaining things as I know it. Please feel free to correct as necessary. } As I have understood it, Gaussian randomness forms a predictable pattern when sample size is very high. If we take ...
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1answer
280 views

References to Random Matrix Theory

I am looking for some good references - books/lecture notes/articles which contains Random Matrix Theory for Physicists. I am not particularly looking for mathematical rigor in derivations. I am more ...
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3answers
124 views

When exactly is “God playing dice”? (Question on Hamiltonian and ground state, actually)

There is something I don't get: So I read that by applying an operator to the wavefunction (aka. measuring stuff), it is as if the wavefunction collapses onto one defined state which is an eigenstate....
0
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1answer
137 views

Can quantum computer provide random or just pseudo-random number, or none of both? [closed]

Can quantum computer provide random or just pseudo-random number, or none of both? It's a bit confusing me, since collapse of wave function once measured.
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2answers
126 views

Is the momentum of a particle both uncertain and, independently, also random?

Is momentum of a particle "random" because it is uncertain, or is it uncertain in addition to being random? Is the uncertainty principle and quantum randomness different names the same physical ...
6
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2answers
569 views

“Randomness” versus “uncertainty”

Highly rated PhysicsSE contributor @CuriousOne regularly makes the following claim about quantum mechanics (e.g. here): There is no randomness in quantum mechanics, there is only uncertainty. I ...
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1answer
81 views

How to quantify the level of non determinism / randomness in the universe

I recently read a little about the Bell test (I'm not a physicist, but reasonably well educated) and I started wondering if there is a way to express the level of non-determinism as a single number ...
26
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2answers
3k views

Could the randomness of quantum mechanics be the result of unseen factors? [duplicate]

The possibility of randomness in physics doesnt particularly bother me, but contemplating the possibility that quarks might be made up of something even smaller, just in general, leads me to think ...
1
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1answer
520 views

What does it mean that an electron's position is described by probability?

I just read an answer to a Phys.SE question about why electrons don't collide with protons where an answering user said: In quantum mechanics, an electron doesn't have a definite position or ...
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2answers
827 views

Does quantum randomness measurably affect macro-sized objects?

I understand that while it is believed that there is no true randomness on the macro scale, there is true randomness on the quantum scale. A previous theory that quantum processes could be determined ...
9
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4answers
457 views

Is there a mathematical basis for Born rule?

Wave function determines complex amplitudes to possible measurement outcomes. The Born Rule states that the probability of obtaining some measurement outcome is equal to the square of the ...
0
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1answer
183 views

Does the randomness of QM do much in everyday life? How much? [closed]

My apologies if in its current state this question isn't squarely suited here; I've worked it until it seemed reasonably articulate. Feel free to move it if it'd be better received elsewhere. ...
0
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1answer
475 views

Half wave plate in front of polarising beam splitter?

I have seen (in e.g. quantum random number generators) a half wave plate in front of a polarising beam splitter. But why do we need it and what would be different if we did not have it?
34
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5answers
6k views

Why do all the atoms of a radioactive substance not decay at the same time?

Why does the substance decay at a rate which is proportional to the amount of the substance at that moment? As all atoms are in hurry to become a stable atom and as their decay do not depend on any ...
3
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3answers
2k views

How do particles “know” when to decay?

So, as I understand it, in a substance that is made of radioactive elements, the half-life tells us how long until the half of those atoms decay into their next atom [is there a name for that: the ...
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2answers
132 views

Quantum fortune teller

A diffraction pattern in a double slit experiment only occurs if randomness is preserved for which way the photon goes and once certainty is determined by actual measuring the pattern is lost. Can ...
10
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2answers
2k views

Why does the Stern–Gerlach quantum spin experiment conflict with classical mechanics?

My understanding of the Stern–Gerlach experiment is that neutral (0 total charge) particles are sent through a non-homogeneous magnetic field, with the expectation that the field will push that ...
2
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0answers
2k views

Are radioactive decays truly random? [duplicate]

By truly random I mean that IF we knew the position and velocity of every particle in radioactive isotope, could we predict when the decay would happen?
3
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1answer
508 views

What do we mean by “typical state”?

My question is somehow simple, but not trivial. I'm reading many articles about the ER=EPR correspondence. There are some articles which study this proposal from a field theory point of view (one ...
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2answers
191 views

Proving (instead of discovering) the laws of quantum mechanics

A single toss of a fair coin cannot be predicted. But if we observe a large number of tosses, we can prove mathematically the law that roughly half of them will show up heads. The movements of ...
25
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6answers
3k views

Quantum random numbers from a laser — simplest setup?

I'm a software / maths guy who would like to build a physical setup for generating quantum random numbers. I have no physics background, so bear with me. Background The project is for a public ...
58
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9answers
5k views

Is the uncertainty principle a property of elementary particles or a result of our measurement tools?

In many physics divulgation books I've read, this seems to be a commonly accepted point of view (I'm making this quote up, as I don't remember the exact words, but this should give you an idea): ...
91
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7answers
44k views

Is the universe fundamentally deterministic?

I'm not sure if this is the right place to ask this question. I realise that this maybe a borderline philosophical question at this point in time, therefore feel free to close this question if you ...