Questions tagged [physics]
Questions related to the application of Mathematica to problems in physics.
967
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Clebsch–Gordan coefficient calculation for L-S basis in system of three particles
I am trying to calculate eq (A3)
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1
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61
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StreamPlot3d for the magnetic field of a loop
I am trying to go beyond StreamPlot in the case of a current loop that produces a magnetic field. My code works for StreamPlot, but does not end when I use the same field expressions with StreamPlot3D....
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Checking the formula for solving the Poisson equation with an integral over all of space
EDIT: According to 2.2.3 Rigorous derivation, if we find the integral $u(x,y) = \int \int G(x,y,m,n)f(m,n) dm dn$ then we obtain a function that satisfies the Poisson equation $\nabla^2u(x,y)=f(x,y)$. ...
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Help me figure out how to solve the gravitational lens equations [migrated]
I want to simulate gravitational lensing. In the article LENSINGGW: a PYTHON package for lensing of gravitational waves there is this fragment [page 3]:
My research: As far as I understand, this is a ...
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Computing eigenvalues and eigenvectors of large matrix and scaling of data
I am trying to plot graphs 1(a1,b1,c1) from https://arxiv.org/pdf/2404.14971 by solving Eq.1. This gives a matrix. For the energy plot, we have to find the lowest 2 eigenvalues and find the difference ...
- 341
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Package for calculating ADM mass for a given asymptotically flat metric tensor
I am asking for Mathematica package, such that for the input of an asymptotically flat Lorentzian metric tensor $g_{\mu\nu}$ it will give the ADM mass of the object that creates the corresponding ...
2
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1
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124
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Mathematica package for validating effective string theory solution
I am asking for Mathematica package that given an input of:
symmetric matrix $G_{\mu\nu}$, antisymmetric matrix $B_{\mu\nu}$ and a scalar function $\Phi$
will check whether it is a solution to the one-...
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67
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Need help in plotting a graph calculated with ``NIntegrate``
This is my Mathematica code,
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4
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1
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107
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How can I combine a selections of video frames into a composite using Mathematica?
I'd like to use Mathematica to be able to turn videos of my students dropping balls into a composit image of selected frames showing the path of the ball. Like a multiple exposure image.
So far, I've ...
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Why is NDSolve ignoring two PDEs out of three ones I am solving?
I am solving the following coupled system of 3 PDEs modelling a 1D membrane coupled to a 1D fluid flow field underneath.
However, on putting them into NDSolveValue (and trying with FEM), it says the &...
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Stabilise equations for motion of Inextensible string subject to spatially non-uniform forces
I would like to simulate the motion of an inextensible membrane in 1D as an inextensible string subject to spatially-dependent body forces. For now, I would like it to be constrained at both ends. I ...
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How to simplify the results of squared amplitude calculations in FeynCalc?
I want to calculate the squared amplitude of the Feynman diagram of double-pion photoproduction using FeynCalc package. Here is the code I created:
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3
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2
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128
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Plot of Density of States Using DiracDelta Function [duplicate]
I am trying to plot the density of states $$ N(E)= \frac{1}{N}\Sigma_{k} (\delta{(E - \epsilon_{k}))} $$ where $\epsilon_{k} = -2t*[cos(k_x)+cos(k_y)]$ and $k$ goes from $-\pi$ to $\pi$. For this plot,...
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Need explanation on data[[i]][[1]]
I am trying to train a physics model and then check its profile. For this model, data for physics model is defined with:
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How to solve a matrix differential equation $\frac{d X}{dt} = i(X Y- Y^\dagger X)$?
In eq (21) on page-5 of this article, we have matrix
HEP = (\[Omega]/2)*{{-2*I, 1}, {1, 0}};
and I am interested in finding matrix ...
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