Questions tagged [algorithms]
For questions about an algorithm as it relates to physics. DO NOT ask how to implement an algorithm, questions like that belong on Stack Overflow or Computational Science. DO NOT ask about the efficiency of an algorithm, or other such questions, questions like that belong on Computational Science.
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Could a computer unblur the image from an out of focus microscope?
Basically I'm wondering what is the nature of an out of focus image. Is it randomized information? Could the blur be undone by some algorithm?
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Upper bounding the Kolmogorov Complexity of the Standard Model
The Kolmogorov complexity of a hypothesis/theory/model is the shortest computer program that simulates it, regardless of how inefficient executing that program may be in terms of memory and time. I'm ...
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Could quantum computers break any cipher? [closed]
I've been told that physicists and computer scientists are working on computers that could use quantum physics to increase significantly computation capabilities and break any cipher so cryptography ...
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If quantum computation is reversible, what is the point of Grover's search algorithm?
Wikipedia et al say the following about Grover's algorithm:
Although the purpose of Grover's algorithm is usually described as
“searching a database”, it may be more accurate to describe it as
“...
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Why use Crank-Nicolson over Matrix Exponential when solving Schrödinger's equation?
For Schrödinger's equation,
$$\psi(x,t+\Delta t)=e^{-i H\Delta t}\psi(x,t)\approx\frac{1-\frac{1}{2}i H\Delta t}{1+\frac{1}{2}i H\Delta t}\psi(x,t).$$
The right-most expression is the Crank-Nicolson ...
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Exact diagonalization to resolve ground state degeneracies
I am studying a perturbed Toric Code model that is not analytically solvable.
On a torus the ground state degeneracy of the unperturbed model is 4.
Once we turn on the perturbation there is a change ...
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Using a time-like boundary as a computer?
Question and Summary
Using classical calculations and the Robin boundary condition I show that one calculates the anti-derivative of a function within time $2X$ (I can compute an integral below)
$$\...
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Shor's algorithm - why doesn't the final collapse of the auxiliary qubits cripple the computation?
Let's look at quantum subroutine of Shor's algorithm (image source):
Hadamard gates create superposition of all (exponential number) values for input qubits.
Then we perform a classical function ...
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Numerical Ising Model - Wolff algorithm and correlations
I'm doing some numerical Monte Carlo analysis on the 2 dimensional Ising model at the critical point. I was using the Metropolis 'single flip' evolution at first with success, though it suffers from ...
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Github for Physicists
I am wondering if there is a platform to which researchers share or publish the code they used in their research. I noticed that many researchers explain their algorithm and math and present the ...
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Explanation of relaxation method for Laplace's equation?
Currently reading through Introduction to Electrodynamics (4th Edition) by Griffiths. I'm trying to wrap my head around Laplace's Equation, here are a couple quotes that I'd like to understand a bit ...
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Deutsch-Jozsa Algorithm for Non-Balanced+Non-Constant Functions?
Note: I'd imagine this will be a simple yes/no question for people better versed in this topic than myself, but nevertheless I'll provide a bit of background first for the edification of anyone who ...
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Quantum XOR: How do you generalize it?
Consider the classical XOR Gate:
Given a 2 bit system: $G = [u_1, u_2]$
$$XOR(G) = (u_1 + u_2) \ mod \ 2$$
Is the following a good generalizaiton of a Quantum XOR Gate:
Given a 2-qubit system: $...
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Is the universe's Kolmogorov complexity growing over time?
The Kolmogorov complexity of a deterministic universe is constant.
The Kolmogorov complexity of a nondeterministic universe grows over time. It grows whenever something happens that is not ...
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Deutsch's Algorithm. Unitary Transform $U_f$
I'm studying Deutsch's algorithm and I keep coming across the phrase along the lines of "There is a unitary transform (a sequence of quantum gates) $U_f$ that transforms the state $|x\rangle |y\rangle ...
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