Questions tagged [physics]
Questions related to the application of Mathematica to problems in physics.
1,027 questions
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Problem with evaluating the Trace of Hadronic tensor of spin 3/2 particle
I am trying to evaluate the Diractrace using Feyncalc package. The expression involves projection operator 'ab' which comes from completeness relation of spin 3/2 particles (Delta-). I am having some ...
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Non linear GPE With Imaginary Current Nonlinearity
I want to solve the Equation 22 and generate fig 3(a) given in the paper https://arxiv.org/pdf/1812.04672.
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While solving set of differential equations with NDSolve, I got NDSolve::initf: The initialization of the method NDSolve`StateSpace failed
Now I'm trying to solve partial differential equation by discretizing spatial coordinate. These equations are a kind of fluid equation and the fluid is annihilated at the x=0.
The variables are matter ...
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How to use Schwarzschild geodesic equation in 2D with Energy
I'm trying to plot the motion of a star around a black hole by using the Schwarzschild equations in 2D. I will use only r and φ equations, while the equation for t will be obtained from the energy ...
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Issue with plotting piecewise function
I tried to plot the critical meniscus height of a liquid near a vertical rod (pulling upward) (radius, $r_0$) using the nondimensionalized equation (as $z=y/r_0$ and $r=x/r_0$) given in this paper, ...
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Generating natural structures with Mathematica
I am interested in Fomes Fomentarius or "Tinder Polypore" mushroom patterns
(original photo, diagrams of Voronoi and Delaunay):
At first it seems something simple, like a sunflower seed ...
- 2,590
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Solving a nonlinear partial differential equation using method of lines
I am trying to reproduce Figure 5 of this paper by using the following Mathematica code, which uses the method of lines for NDSolve. Unfortunately, I am not able to ...
- 3,028
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Solving a nonlinear coupled partial differential equation using FD method
I am trying to reproduce the Fig.5 (given below) from this paper.
For this, I have to solve a coupled partial differential equation. The authors of the paper use a type of finite difference method to ...
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Can we merge a piecewise with 2 interpolating functions into one interpolating function?
I have the following Mathematica code:
...
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How to calculate the perturbation for Ricci scalar squared
Consider a perturbation for this metric:
$$
ds^2= \left(g_{\alpha\beta}+ \delta g_{\alpha\beta} \right) dx^\alpha dx^\beta ,
$$
in the form:
\begin{eqnarray}
\delta g_{00}&=&- a^2(\tau)\left( ...
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How to find equation of motions from lagrangian with partial derivative terms?
I am trying to find the equation of motions for the lagrangian given in Eq(22) of this paper. For this purpose, I use the following Mathematica code:
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I am trying to solve nonlinear stochastic $\phi^4$ equation analytically and unable to plot 3D, 2D and line graphs for solutions on mathematica
I am trying to solve a nonlinear stochastic $\phi^4$ model but don't know how can I plot the solutions in mathematica by adding a noise term as space time noise or white noise. Since I am new to ...
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Problem with constructing the trajectory of a particle in a pulsating field obtained numerically by solving a wave PDE
I model the propagation of a pulsating wave. Below is a system of partial differential equations with free boundaries (Neumann conditions), as well as a pulsating component.
Individual components of ...
- 2,665
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Mid Spectrum Entanglement Entropy Of Spin-chain
I want to reproduce Fig. 2(a) from https://arxiv.org/pdf/2403.09608 and Figs corresponding to EE and participation ratio from https://github.com/fabienalet/HKU-MBL/blob/main/Notebooks/...
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Level spacing Spectra and Entanglement Entropy of Spin-Chain
The hamiltonian
$H=\sum_{i=1}^L S_i.S_{i+1}-h_iS^z$.
It is a periodic $S =1/2$ Heisenberg chain in a random magnetic field, $h_i$ drawn from a uniform distribution $[−h, h]$.
The ratio of consecutive ...
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