Questions tagged [computational-physics]
The bridge between theoretical and experimental physics which utilizes numerical analysis, specifically through the use of software, to solve problems in physics. This tag is NOT intended for use in solving problems on paper. Please note that details of writing and/or debugging code is OFF-TOPIC and should be asked at either Computational Science, Code Review or Stack Overflow.
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questions with no upvoted or accepted answers
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Numerical problem in solving the Bogoliubov de Gennes equations- methods to solve?
I am trying to solve an assignment on solving the Bogoliubov de Gennes equations self-consistently in Matlab. BdG equations in 1-Dimension are as follows:-
$$\left(\begin{array}{cc}
-\frac{\hbar^{2}}...
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Upper bounds on phase space momenta
Suppose I wish to calculate the phase space volume for the process $\overline{X}X \to A_1 A_2 A_3 A_4 A_5$ in the CM frame of $\overline{X}, X$ so that $\sqrt{s} = 2m_X$. The volume is given by
$$
V \...
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Do systems of fermions take longer to equilibrate than systems of bosons for complexity-theoretic reasons?
This excellent paper by Scott Aaronson persuasively argues that computational complexity can be relevant for physical processes. In particular, what's hard for a hypothetical Turing machine to do may ...
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An explanation for the Landauer's principle
Has anyone understood the Landauer's principle? What is the current status?
In specific, is there a theoretical derivation of the Landauer's Principle?(not the heuristic one based on Salizard's ...
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Understanding the Relationship Between Stochastic Reconfiguration and Natural Gradient in Variational Monte Carlo
I've been delving into variational Monte Carlo methods, particularly in the context of ground state energy minimization for quantum wave function ansatzes. In my studies, I've come across multiple ...
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Decorrelation times for a 2D Ising Model over a range of temperatures
So, I'm trying to simulate the Ising Model on a 2D square lattice of spins. When exploring the auto correlation of the magnetisation:
Where the auto covariance: $$A(T) = \langle(M(t)\ - \langle M\...
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Simulation of a dispersive crystal mirror
I am trying to simulate a simple setup where I have a point source of broadband light whose light is incident upon a spherical crystal at a central angle $\theta_i$. Assuming Bragg diffraction some of ...
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Do exactly solvable stat mech systems admit efficient algorithms for finite sizes?
I come from a background in statistical mechanics (not algorithm design or complexity theory), and the following question occurred to me that I could use some expert help in beginning to understand. ...
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Numerical Solution of the Propagation-Dispersion equation
I have asked this question on Computational Science and also on Mathoverflow, but no satisfactory answers so far. I thought maybe the physics community could shed some insight on the issue.
I am ...
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Black body simulation
Black body radiation is typically understood from Planck's argument of light resonance in a box, from which the density of states is computed. Now, suppose I want to simulate a black body ...
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Textbooks on algorithms for the perturbative calculation of High energy physics
For the perturbative calculation of High energy physics, I have known some packages such as FeynArts, FeynCalc, MadGraph, CompHEP, GiNaC, and so on. But I am wondering whether there exists a textbook ...
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Estimating the correlation length on a periodic lattice
I am trying to estimate the distance dependent correlation length of on a 2D lattice. Usually if $C(r)$ is the correlation function, I can estimate it as:
$$\frac{1}{\xi(r)} = - \ln\{C(r+1) / C(r)\} $$...
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Can I do anything instructive by simulating QED on a lattice?
For learning something about the degrees of freedom and underlying path integral math, is it possible to do some kind of scalar QED or normal QED simulation on a lattice in the same way Lattice QCD is ...
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Cross product of operators in exponential: numerical solution
Short version:
Numerical solution to a quantum system.
I have my discretised wavefunction is real space $\psi(\mathbf{r})$ and in momentum space $\tilde\psi(\mathbf{k}) = \mathcal{F} \left [ \psi(\...
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