Questions tagged [physics]
Questions related to the application of Mathematica to problems in physics.
1,028 questions
1 vote
0 answers
79 views
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 ...
0 votes
0 answers
68 views
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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2 votes
1 answer
331 views
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, ...
- 1,137
3 votes
1 answer
184 views
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
1 vote
1 answer
136 views
Can we merge a piecewise with 2 interpolating functions into one interpolating function?
I have the following Mathematica code: ...
- 3,028
1 vote
1 answer
139 views
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: ...
- 3,028
3 votes
2 answers
212 views
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
2 votes
1 answer
310 views
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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