Questions tagged [physics]
All issues relation physics and computation theory (excluding computational hardware or use of computers in physics). May include, for example, analog computing, reversible computing, physical analysis of computability (Church-Turing thesis).
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Asymmetric communication between two symmetric parties?
(sci-fi-esque question inspired by Counterpart).
A portal between our world (called $A$) and a parallel world that's exactly the same (called $B$) opens up. Bob sees himself through this portal.
$A$-...
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Best C++ STL container to store bodies in an N-body simulation?
I am writing an N-body simulation in C++ that has to be able to deal with large N ($N \le 10^6$).
Everything has been going well so far, but now that I have started to code in collisions between ...
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Can all non-quantum physical systems be efficiently simulated on a classical computer?
Is it true that simulating classical physical systems is in P, i.e. can be done efficiently on Turing machines or are there known exceptions? I'm thinking of chaotic systems but I'm also curious more ...
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Generalization of computability to continuous for loops?
A computable function, formulated in the sense of mu recursion, can compute a for or do loop over some (possibly infinite) integer range.
I was wondering if a suitable generalization exists that ...
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Do non-linear dynamical systems have the potential to have an edge on other algorithms when it comes to computing NP-complete problems?
In a recent presentation, I've seen the difficulty of NP-complete/NP-hard problems attributed to the fact that they often have "long range" correlations, or at least they can be interpreted ...
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The class of problems that can be solved efficiently using physical means?
By "physical means", I mean, for example, using water pouring down tubes, or combining chemicals, etc. Basically, using some experiment in the physical world to perform some computation. I'...
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Solving the maximum flow problem in the real world
Is it possible to solve the maximum flow problem in the real world, ie. using water running through physical pipes? So you would have a tap at the source node, pipes of various diameter (depending on ...
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What is the quickest algorithm to numerically integrate this function?
Motivation & Question
So I can theoretically build a "computer" to calculate the exact anti-derivative of a particular function.
Using classical calculations and the Robin boundary ...
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Is there any known method to simulate a UTM with an instance family of the three body problem in physics?
I think it would be challenging since the three body problem is about continuous movement and Turing machines execute in discrete steps.
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What problem is this application of simulated annealing trying to solve?
I was reading about simulated annealing on its Wikipedia page, and was drawn to a particular example illustrating the annealing schedule. Below is the picture and its description:
Example ...
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Can one build a "mechanical" universal Turing machine?
This question connects different disciplines so it's awkward to choose a SE site for it, but I'll go with this one because here (I hope) the shared culture will make information transfer easier.
So ...
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Evenly Spaced Points On Smooth Surface
I want to space points evenly (i.e. maximizing minimal distance between two points) on some smooth surface $S\subseteq\mathbf{R}^n$ (usually $n=3$), where I have a projection operator $p:\mathbf{R}^n\...
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Would models of computation in other conceivable universes be Turing complete?
I'm interested in gathering some references that discuss the topic of the relationship between computation and physics.
Specifically, I'm interested in investigating two points of view:
our current ...
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Crossover method for 3D velocity vector genetic algorithm
I am trying to write a genetic algorithm which will learn how to throw a ball at a target. I have successfully implemented code that will graph the projectile motion of a sphere given an input ...
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How does one simulate continuous gravity using a discrete timestep?
While gravity in real life is continuous, computers are limited to discrete calculations.
Therefore, a seemingly correct projectile simulation inevitably drifts off.
For example:
...
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Questions about Seth Lloyd's Programming the Universe?
I have been interested in Seth Lloyd's cosmological model (which proposes that the universe is a computer: https://en.wikipedia.org/wiki/Programming_the_Universe, https://arxiv.org/abs/quant-ph/...
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Do all Cellular Automata have some kind of information boundary? Can all Cellular Automata be modelled with the Bekenstein Bound?
Since they are discrete models, do they have some kind of information boundary? Can all Cellular Automata models be related to the Bekenstein Bound?
https://en.wikipedia.org/wiki/Bekenstein_bound
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Did Wheeler really believe that physics was undecidable?
John Archibald Wheeler was a famous physicist.
It has been stated that he thought that there was a strong connection between undecidability and quantum physics:
This idea was given an early ...
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Is computer science really a branch or sub-branch of physics? [closed]
Given that a computer is basically an electronic machine, is computer science really a branch of electronics, which is in turn a branch of physics?
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The Ising Model and Computational Complexity
I've been told recently that one can use the Ising model can find solutions to certain NP-hard problems, such as Clique, although it doesn't do so in polynomial time.
Googling gets a few Arxiv ...
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Is there any specific model/theory that proposes that the universe is an oracle machine? [closed]
Is there any specific (and well known/famous) model/theory that proposes that the universe is an oracle machine?
Physicist Roger Penrose said his book "The Shadows of the Mind"
It would be just as ...
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Are physical laws uncomputable in any type of computation (according to this article)?
It seems that this article (https://arxiv.org/pdf/1312.4456.pdf) proposes that laws of physics are uncomputable (i.e., they could not be reproduced on a computer), but I'm not sure about it.
In some ...
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Potential General Model of Computation with Physics?
I posted a question about a month back regarding the significance of Turing machines (relative to other models of computation). In that post, I mentioned vaguely some conversion between an input ...
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What is the difference between luma and luminance?
I understand the following (correct me if I'm wrong):
Statements
Luma as the weighted sum of RGB gamma corrected components, but luminance is the weighted sum of RGB linear components.
The gamma ...
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Learning dynamics
I recently learned about Q-learning, a reinforcement learning technique that directly estimates the expected value of taking an action in a state.
I'm wondering if there exists techniques to do "...
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Reference Request: Overlaps between complexity theory and dynamical systems?
Per Wikipedia:
In mathematics, a dynamical system is a system in which a function
describes the time dependence of a point in a geometrical space.
Examples include the mathematical models that ...
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Research in realtime computational physics?
I am aware that there is a considerable amount of interest in computational mechanics for simulation of cloth, hair and other elastica, particularly for animation films. The methods developed by ...
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Patriot Missile Software Bug (Range Gate Calculation) [closed]
Okay so I was reading about the Patriot Missile Software Bug, where to calculate the predicted range gate the missile system relied on the time keeping, however it would convert the whole/integer time ...
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Can normal physics laws be simulated in Digital physics? [closed]
Physics is defined as the study of an object {matter or energy} with its interaction with other objects:
Physics is the study of matter, energy, and the interaction between them.
On the other ...
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Could an NP-hard problem have a mechanical or physical solution method?
Is there any NP-hard problem that we can find a mechanical "polynomial time" solution to? For example, suppose we construct a graph out of something physical, e.g. we have have pipes through which we ...
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Undecidable problems limit physical theories
Does the existence of undecidable problems immediately imply the non-predictability of physical systems? Let us consider the halting problem, first we construct a physical UTM, say using the usual ...
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