Questions related to the application of Mathematica to problems in physics.

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2
votes
0answers
98 views

Schrödinger equation for Hydrogen atom

I'm trying to solve Schrödinger 1D equation for hydrogen atom but I found several difficulties. To get in context I want to solve this equation For Z and l real and arbitraries. To start with I ...
12
votes
1answer
372 views

How to numerically solve a 1-d time-independent Schrodinger equation?

The point is to solve the eigensystem of the given Hamiltonian. I tried ParametricNDSolve combined with FindRoot to search for ...
11
votes
3answers
461 views

Using NDSolve to find particle trajectory

I'm trying to simulate a particle in an electric and magnetic fields, but numerically instead of analytically. This is basically solving the equation $$q \cdot \left(p'\times B\right) + q\cdot E = m ...
-5
votes
0answers
27 views

what's my air speed if i know these details [closed]

What is the minimum air speed required of an F4 phantom aircraft to accelerate at 10g while pulling the nose up from a 20 degree pitch down attitude?
1
vote
1answer
98 views

Phase Portrait to Differential Equation [closed]

I posted this question on Math.SE and have received a satisfactory answer in the context of that website. I am re-posting it here to get input from Mathematica users. Why would I receive a different ...
6
votes
3answers
244 views

Labeling solutions of an Eigenvalue equation involving Bessel functions

I'm solving the Schrödinger equation for a particle in an annular geometry with hard wall boundary conditions and I've reduced it to the following equation: $$J_m(k\,R_1)\,Y_m(k\,R_2) - ...
8
votes
0answers
119 views

How best to simulate n-body systems in a functional way

I want to simulate a N-body system in the most functional way possible. The system I'm modeling are metallic colloidal particles in a solution of peroxide water, as here ...
1
vote
1answer
41 views

Get Isotope Data and Electron Mass in Same Units - kg and Kilograms

I'm trying to find the nuclear mass of $^{238}\text{U}$. To do this, I subtract the electron mass from the atomic mass. I'd like to find the final answer in kilograms. I'd also like to use ...
0
votes
1answer
47 views

Problem in trying to solve a differential equation [closed]

I'm trying to solve a differential equation but not getting a solution. Some references I read gave me hits about using a runge kutta method. I'm new to the software, any hints regarding this error ...
3
votes
1answer
131 views

Recognize physical constants?

Is there some way to ask Mathematica to recognize physical constants, such as 32 or 9.81 (gravitational acceleration, in different units, at Earth's surface)? I have in mind something like the ...
6
votes
0answers
125 views

Heat convection differential equations from 1952 - Mathematica “fails to converge”

I am trying to solve a fundamental problem in analytical convective heat transfer: laminar free convection flow and heat transfer from a flat plate parallel to the direction of the generating body ...
5
votes
2answers
204 views

Solve numerical differential equations at `t->Infinity`

I have a first order non-homogeneous system of differential equation (100+ equations, so no hope to solve them analytically, due to the Abel–Ruffini theorem). If I solve them using ...
7
votes
1answer
226 views

Synchrotron Radiation and ListDensityPlot

I'm trying to reproduce the following plots: As described by this blog entry: Synchrotron radiation As you can see in the linked article, the task is essentially to make a ...
1
vote
1answer
295 views

How can I use Mathematica to solve a Stefan Problem using an explicit scheme?

I would like to plot the temperature distribution for a particular case. the problem is stated in the paper, behind a paywall here, summarized as Consider a one-dimensional container of length l, ...
8
votes
2answers
229 views

Boson commutation relations

I have tried to adapt this answer to my problem of calculating some bosonic commutation relations, but there are still some issues. The way I'm implementing the commutator is straightforward: ...
2
votes
3answers
686 views

draw part of parabola using graphics

today I was doing my physics homework. one of the questions was draw velocity-time and position-time graphs from the acceleration-time graph. So for the first step I draw acceleration-time using ...
1
vote
1answer
63 views

Combinatorica and DualPartition function (for a Young diagram)

I am trying to understand how to evaluate the arm and leg functions of a Young tableaux using Mathematica. To do so I need the Combinatorica package. Then apparently the command ...
2
votes
1answer
93 views

Solve 2D diffusion equation in polar coordinates

I am trying to solve the diffusion equation in polar coordinates: $\frac{\partial u}{\partial t} = D \left( \frac{\partial^2 u}{\partial r^2} + \frac{1}{r} \frac{\partial u}{\partial r}\right)$ ...
0
votes
0answers
106 views

Three Body Problem Equilateral Triangle

I'm currently working on showing that the equilateral triangle arrangement of the three-body problem has an analytic solution. So far I've written the equations of motion of each body into Mathematica ...
9
votes
1answer
956 views

NDSolve::ndcf: Repeated convergence test failure. How to solve?

I am trying to simulate a system of $n$ pendulums with some friction in Mathematica 9. This is the code I am using: ...
8
votes
1answer
345 views

Diverging solution to coupled second order ODEs from NDSolve

For a physics application I am considering the radial Bogoliubov-de Gennes equations in two dimensions. In dimensionless form they read as follows $$ \begin{cases} ...
6
votes
1answer
2k views

Efficient implementation of cubic equation of state

...In this case the Peng Robinson Equation of State. Equations of state are empirical equations with parameters derived from experimental data. They are used to predict pure component and mixture ...
0
votes
0answers
41 views

How to combine two matrices.? [duplicate]

let A, B are any 4 by 2 Matrices , i want to know whether it is possible to obtain a 4 by 4 matrix by using equation A=B Thanks in advance
1
vote
1answer
87 views

Polarization sum in FeynCalc

I think I know how to sum over final state fermion spins (FermionSpinSum[...]?) but what is the analog expression (in FeynCalc) if you have two or more polarization ...
1
vote
0answers
57 views

How to implement time dependence in the DoFun package?

DoFun is a very usefull mathematica package that helps to write Dyson-Schwinger and FRG flow equations when these are to complex to write down by hand. You can download it here and read it's manual ...
1
vote
1answer
132 views

Calculating the normalization constant for a wavefunction

How can I compute the normalization constant for a quantum mechanics wave-function, like $\Psi(x) = N \exp(-\lambda x^2/2)$ by using Mathematica? (The normalization constant is $N$).
0
votes
0answers
42 views

How to combine similar terms in a density matrix expression? [Ref: Quantum Computing]

I tried the following : Simplify, FullSimplify, and Expand. Due to this problem, I am not ...
35
votes
5answers
8k views

Find eigen energies of time-independent Schrödinger equation

I'm trying to get the eigenvalues of a one dimensional time-independent Schrödinger equation, $-\frac{h^2}{2m_0}\frac{d^2\psi}{dx^2}+U(x)~\psi=Ei~\psi$ where U(x) is some potential and Ei is the ...
1
vote
1answer
93 views

Divergence of $1/r^2$: Mathematica yields 0, while the correct answer is a DiracDelta

In spherical coordinates, the divergence of a point charge is $4 \pi \delta (r)$, the three-dimensional Dirac delta function. In ...
2
votes
2answers
193 views

Attempting to use NDSolve to plot harmonic oscillator solutions

NDSolve[{ (-y''[r]/1880) + (470 (0.04077)^2 r^2 - 48 + 1/(1880 r^2)) y[r] == 0, y[0] = 0, y'[0] = 0}, y, {r, -4, 4}] I use this but get errors and am ...
2
votes
2answers
204 views

Help with NonLinearModelFit

I have a question about fitting data with a model. I have a quite complicated model, based on Arctans, modified Bessel functions, etc, that I want to fit to my data, a table of couples (minimal ...
2
votes
1answer
88 views

Singularity while solving PDE

I have to solve a PDE (in the context of the functional renormalization group in physics). I have a function of two variables, $U(l,p)$. I know $U(0,p)=U_0(p)$ and then I have an equation (eq925) that ...
5
votes
1answer
119 views

A 1D numerical integral Mathematica cannot compute, from physics

A well know result in theoretical physics is that a sum over Matsubara fermionic frequencies, i.e.: $$ S = \sum_{n=-\infty}^{\infty} h(\omega_n) \hspace{32pt} \omega_n=(2n+1)\frac{\pi}{\beta} $$ can ...
6
votes
2answers
385 views

Plotting 2-D Electron Density Carbon Atoms

I need to create a 2-D electron energy density plot in Mathematica to compare with my STM experimental results in my lab class. This would be done by plotting the sum of the symmetric and ...
1
vote
0answers
389 views

Time evolution of a bispinor [duplicate]

The effective Hamiltonian for polariton graphene is given by: ...
0
votes
0answers
51 views

Plotting a parameterized vector in the x-y plane

I am trying to plot the trajectory of a parachutist descending at a constant vertical rate of 8 m/s while a south wind also blows at a rate of 8 m/s. He initially jumps from a height of 300 m. I am ...
6
votes
2answers
339 views

Time evolution/dynamics of circular plate with hole (Biharmonic equation and stiffness)

On this Mathematica.SE form, there exists information on how to use Mathematica to demonstrate the vibration of a circular membrane and the deflection of an orifice plate (the latter I had raised ...
7
votes
3answers
312 views

FEM Solution desired for “Plate with orifice” deflection: Application of Boundary Conditions and use of Regions

I found the deflection of an orifice plate (circular plate with a hole) subject to uniform pressure using Mathematica's NDSolve functionality. The plate is fixed at its outer circumference and is ...
3
votes
1answer
103 views

How to reduce an expression into user-defined variables?

In the following code, I define a set of matrices. Then, I define a function that calculates the commutation relation relation between these matrices ...
34
votes
4answers
3k views

Is there something like DensityPlot3D to visualize atomic orbitals?

I'm visualizing some hydrogen like atomic orbitals. For looking at plane slices of the probability density, the DensityPlot function works well, and with something ...
7
votes
0answers
149 views

Interfacing Red Pitaya board with Mathematica [closed]

I just discovered the Red Pitaya board and borrowed a unit to play during this weekend. Surprisingly I did not find any reference to Mathematica on the Red Pitaya forum, nor did I find any reference ...
4
votes
1answer
136 views

Help nedeed for understanding NDSolve architecture -Vacuum Heating Simulation

I am a beginner in mathematica and I am facing a problem that is way bigger than my knowledge.. I am tryng to simulate a semplificated version of Brunel Effect, wich is a Laser-Plasma interaction ...
2
votes
0answers
129 views

Creating an orrery

I am interested in creating an orrery, ideally with SystemModeler. I have been experimenting with the MultiBody library since that allows you to do animations. The most relevant example seems to be ...
2
votes
1answer
127 views

Equal flow boundary conditions

I'm having the following issue that can not find a solution , by using this boundary condition v[0, t] == u[1, t] that Mathematica does not understand, someone ...
0
votes
0answers
165 views

FeynRules issue when trying to export UFO file

I am having problems with the UFO file generated by a very simple model using FeynRules. The following error occurs when MadGraph tries to import the "Model_UFO" file: ...
21
votes
3answers
845 views

How to plot an emission spectrum?

If I have a list of data with various wavelengths in nanometers, how would I plot them on a graph so it looks like this: So far I have managed to plot a spectrum in ...
41
votes
6answers
3k views

ColorData[“VisibleSpectrum”] is wrong?

I am trying to visualize the visible spectrum using the built-in ColorData["VisibleSpectrum"] function which "colors based on light wavelength in nanometers". But I ...
1
vote
0answers
75 views

Slater Koster parameters generated using Mathematica

Here is a link where people describe how one can generate the entries of the Slater Koster parameter table seen here as Table of interatomic matrix elements. The ...