Questions tagged [physics]
Questions related to the application of Mathematica to problems in physics.
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SixJSymbol not triangular in basis transformation
The basis transformation is given by
$$\left| J^{P}, jd \right\rangle = \sum_ {S} (-1)^{J + L + Sd + Sq}\sqrt {(2 S + 1) (2 jd + 1)}\, \biggl\{\begin {array} {ccc} L & Sq & J \\ S & Sd &...
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TensorD extension pack for the Package-X
Does anyone have a copy of TensorD extension pack for the Package-X?
The Package-X is a Mathematica package for QFT calculations. Unfortunately, it is no longer developed and the official website (...
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Calculate and transfrom the metric to the orthonormal frame
Let's suppose, the line element is like this:
$$ds^2 = -a^2(1+2\psi)d\tau^2 - 2a^2 B_idx^i d\tau + a^2(1-2\phi)(dx^2 + dy^2 + dz^2)$$
I like to get the output of the metric components from it, ...
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2D Projected Stocastic GPE Equation With Vortices
I am trying to solve the Projected Stochastic Gross-Pitaevskii equation with periodic boundary conditions from this paper https://arxiv.org/pdf/1905.05263. This equation can be found in https://...
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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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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 ...
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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 ...
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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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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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