Questions tagged [wolfram-physics]
Questions relating to the Wolfram Physics project, and how to use Mathematica for it.
16
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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:
...
3
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2
answers
131
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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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How do I couple an 1D PDE to a 2D Laplace equation?
Recently I've come across the following system governing the spreading of an evaporating droplet. The height of the droplet $h$ is defined by the following equation
$$\frac{\partial h}{\partial t}=-\...
- 547
1
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2
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98
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How to demonstrate the acceleration using spherical coordinates and spherical unit vectors?
I've been trying to use Mathematica to demonstrate using spherical coordinates and unit vectors the acceleration for a particle moving in a sphere. Nevertheless, I'm actually not that skilled in ...
2
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1
answer
150
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How to Optimize Integro-Differential Equation Solving Time in Mathematica?
I'm trying to solve an integro-differential equation numerically in Mathematica that models the evolution of a physical system . However, the computation takes a very long time and doesn't yield a ...
- 33
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158
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Dirac equation for a Coulomb potential in 2D with NDEigensystem
I want to numerically solve the ground state wave function of the hydrogen atom with the Coulomb potential using the NDEigensystem. Here is the code to get the ground state wave function from the ...
- 51
3
votes
1
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135
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Second order Poisson ODE
I have a 2nd differential Poisson equation for the electric field in a semiconductor (application for a MOS simulation, hopefully).
I have the formula:
with the condition that after a certain value(...
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1
answer
32
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How to plot from a condition and limit number of solutions?
I am trying to plot the band structure of some quantum mechanics problems, but I am really lost. From the math I get the following relationship between q and k
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Trying to interest Wolfram in correcting an error in a built-in function [closed]
There is a Mathematica function that produces a nonsense, non-physical output and I haven't managed to interest Wolfram in the problem. The function is:
...
- 137
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141
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Feynman Two Loop Integrals
Is there any reference suitable for a beginner that you recommend for learning two loop integrals evaluation by hand ( and/or some package) that you know of?
Thank you very much.
- 29
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Is it possible to define substitution rules on edges instead of nodes [Wolfram Physics]?
I have a small question about the way substitutions work in the Wolfram Physics project, which might be a general question about how to add edges between nodes and edges.
Running a Wolfram Physics ...
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2
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What does the command '$FAVerbose = 0' do in FeynCalc
I have seen this right below the "<<FeynCalc`" command that loads FeynCalc.
$LoadAddOns={"FeynArts"}; <<FeynCalc;
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394
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four-dimensional Levi-Civita
Consider we have these four vectors $p^{\mu}$, $q^{\nu}$, $k^{\rho}$, and $k'^{\sigma}$.
How can we calculate
$$
\epsilon_{\mu\nu\rho\sigma} p^{\mu} q^{\nu} k^{\rho} k′^{\sigma}$$
in Mathematica, ...
- 11
2
votes
1
answer
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Plotting equation of motion in mathematica [closed]
Suppose I have an equation of a moving body in Newtonian Mechanics e.g.
$ax^2=(b/t^4)+(c/t^2)$
how can I plot a x-t graph in mathematica with a range for the constants a, b and c from 0 to 5 with ...
- 21
4
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How to recreate these physics style graph plots?
The new graphs from this blog post look really nice in a dark background:
How to recreate the largest graph from above?
What I've tried
Nothing yet... there is probably a link or notebook that has ...
- 31.6k