Questions tagged [physics]
Questions related to the application of Mathematica to problems in physics.
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Differential complex equations in cosmological problem
I want to solve a differential equation of second order with complex initial conditions. Despite I have wrote all the code with detail, I am still facing some problems I might want to review here. The ...
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Poincaré section of the particle motion near the black hole horizon
I am trying to recreate the Poincaré sections given in Figure 2 of this paper.
For this purpose, I use the following two methods:
Method1: Using ResourceFunction["ClickPoincarePlot2D"]
<...
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NDSolveValue is unable to provide a solution because of boundary conditions
I have the following Mathematica code for solving a partial differential equation, which I took from this paper (page 6, 10) for B = 0 (which has ...
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How to get rid of division by zero errors in a vector field?
Im currently learning Mathematica and have little to no expirence.
What im trying to do is plotting certain Fieldlines of a Dipol-Vectorfield.
I found a Method that works as long as no line aproaches ...
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Issue in the calculus of inverse of terms from a list
to begin i want to warn you that i am a beginner in mathematica. I have to create a function that calculates the impedance total of an association of n (electronical) components.
So the formula is 1/Z(...
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Color issue with Plot
I would like to print different graphs, and print them in different colors. However, when I use the common way to write it, it doesn't work.
For my project (physics electronic), I have created two ...
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How to create an interactive Poincare section from the given code?
Here we discussed Poincare section for perturbed string model taken from the paper Chaotic dynamics of a suspended string
in a gravitational background with magnetic field. We try to reproduce some ...
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Integrating Over a Conditional Time-Dependent Region
I'm experimenting with integrating over regions so I can check some physics simulations. Here's the rundown of what I'm attempting to do.
I have a rectangle that I'm rotating with a parameter:
...
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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 ...
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Solving a ODE (Peeble's Equation) with initial condition a the maximum input range
I have a differential equation which is,
$$
\frac{d X_e}{dz} = \frac{C_r(z)}{H(z)}\times \frac{1}{(1+z)}\Big[\frac{38\eta T^3}{25\pi^2}\alpha (T)X_e^2 - b(T)(1 - X_e) \Big]
$$
Where
$$
\alpha(T) = \...
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Metric tensor coordinate transformation with off-diagonal components
I know there is already an answer for this type of question given here: Computing the metric tensor under a coordinate transformation but the answer is not satisfactory as it is not clear to me how I ...
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Numerically solving radial Schrödinger equation with Yukawa potential
I am trying to solve the radial Schrödinger equation using NDEigensystem but I am running into some issues. There are posts about doing this (see here for example), ...
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Manual updating of function in Do loop
Previously I had asked a question about solving Maxwells equations with boundary conditions, here Machine overflow when defining boundary conditions.
I have managed to successfully run the code ...
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A code to calculate Einstein tensor [duplicate]
I use the following MA code to calculate Einstein’s tensor. I’m asking about the zero component of the Einstein’s tensor, is it correct?
Because I think $G_{00}$ should contains the terms in the zero ...
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Calculating and collecting the terms of the zero component of the Einstein’s tensor
I try to calculate the $G_{00}$ of the Einstein tensor
$G_{\mu\nu}= R_{\mu\nu} -\frac{1}{2} g_{\mu\nu} R$
for the metric:
$g_{00}=-a^2(\tau)\left( 1+2 \phi^{(n)}\right),$
$g_{0i} = a^2(\tau)\left( \...
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