Questions tagged [determinism]

Use this tag for questions related to the concept of determinism, the idea that all events in the universe can be predicted from some set of initial conditions.

359 questions
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Why do people categorically dismiss some simple quantum models?

Deterministic models. Clarification of the question: The problem with these blogs is that people are inclined to start yelling at each other. (I admit, I got infected and it's difficult not to raise one's electronic voice.) I want to ask my question…
G. 't Hooft
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126
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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 think that this is a duplicate or inappropriate for…
55
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Norton's dome and its equation

Norton's dome is the curve $$h(r) = \frac{2}{3g} r ^{3/2}.$$ Where $h$ is the height and $r$ is radial arc distance along the dome. The top of the dome is at $h = 0$. Via Norton's web. If we put a point mass on top of the dome and let it slide down…
48
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Do identical starting conditions always lead to identical outcomes?

My friend and I are discussing whether or not physical phenomena are deterministic. Let's say, for example, that we have a 3-dimensional box with balls inside of it upon which no gravitational forces are acting. The balls each have their own size,…
Sandi
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Is Stephen Wolfram's NKS, an attempt to explain the universe with cellular automata, in conflict with Bell's Theorem?

Stephen Wolfram's A New Kind of Science (NKS) hit the bookstores in 2002 with maximum hype. His thesis is that the laws of physics can be generated by various cellular automata--simple programs producing complexity. Occasionally (meaning rarely) I…
39
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Discreteness and Determinism in Superstrings?

So Gerard 't Hooft has a brand new paper (thanks to Mitchell Porter for making me aware of it) so this is somewhat of a expansion to the question I posed on this site a month or so ago regarding 't Hoofts work. Now he has taken it quite a big step…
37
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Why do people rule out local hidden variables?

I bet the automatic response to my question would be "Bell's theorem" and of course I am not disputing Bell's proof. I am however uncertain of one of his assumptions. The so called "no conspiracy" assumption states that we somehow posses this…
36
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Why is superdeterminism generally regarded as a joke?

Before anything, I'm sorry for being an outsider coming to opine about your field. This is almost always a stupid decision, but I do have a good justification for this case. I've been reading about superdeterminism and it bothered me that most of…
35
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Why can't the outcome of a QM measurement be calculated a-priori?

Quantum Mechanics is very successful in determining the overall statistical distribution of many measurements of the same process. On the other hand, it is completely clueless in determining the outcome of a single measurement. It can only describe…
34
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4 answers

What combinations of realism, non-locality, and contextuality are ruled out in quantum theory?

Bell's inequality theorem, along with experimental evidence, shows that we cannot have both realism and locality. While I don't fully understand it, Leggett's inequality takes this a step further and shows that we can't even have non-local realism…
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What situations in classical physics are non-deterministic?

In Sean Carroll's book "The Big Picture," he states (chapter 4, page 35): Classical mechanics, the system of equations studied by Newton and Laplace, isn't perfectly deterministic. There are examples of cases where a unique outcome cannot be…
31
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Deterministic quantum mechanics

I came across a very recent paper by Gerard 't Hooft The abstract says: It is often claimed that the collapse of the wave function and Born's rule to interpret the square of the norm as a probability, have to be introduced as separate axioms in…
30
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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 deterministic. However, the relationship between a…
27
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How can a particle's position be random and uncertain in quantum mechanics if it is already pre-determined in relativity?

In relativity, to my knowledge, the path of an object is described by its worldline in spacetime, and since time is a part of the spacetime geometry, an object's worldline--in a sense--always exists on this “block of time” as I heard the PBS…
27
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6 answers

Conservation of information and determinism?

I'm having a hard time wrapping my head around the conservation of information principle as formulated by Susskind and others. From the most upvoted answers to this post, it seems that the principle of conservation of information is a consequence of…
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