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

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41
votes
1answer
2k views

Measuring fractal dimension of natural objects from digital images

This is a useful topic. A college physics lab, medical diagnostics, urban growth, etc. - there is a lot of applications. On this site by Paul Bourke about Google Earth fractals we can get a high ...
28
votes
8answers
3k views

Circuit drawing in Mathematica

This past semester I taught an introductory electromagnetism course and had quite a nice time using Mathematica to draw all sorts of figures and diagrams (mostly for problems and etc.). However, I was ...
26
votes
7answers
1k 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 ...
17
votes
1answer
855 views

The Orbit and Perigee of the Flamsteed comet

Historical context This year we have the 330-th anniversary of the Battle of Vienna - one of the great formative events of European history, it took place on September 12, 1683. Kara Mustafa, Grand ...
16
votes
3answers
597 views

Create an adaptive amount of local variables for error propagation

I intend to write a function which calculates the result and the error for any formula with any amount of variables using the Gauß Error Propagation. The error $\mathrm{d}R$ for a function $R(a,b,c)$ ...
15
votes
4answers
2k 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 ...
14
votes
3answers
715 views

Constructing a symbolic Hermitian matrix

I need to construct a symbolic Hermitian matrix like m = { { n, a, b, b}, {Conjugate[a], n, b, b}, ... } but I am not able to set ...
12
votes
3answers
446 views

How can I simulate this toggle mechanism?

I've been introduced to Mathematica very recently. Basically, I haven't actually "solved" anything in my Mathematica lifetime, but I've done some simulations. With my fractional knowledge, I tried ...
7
votes
3answers
309 views

1D quasicrystal: points on a line nearest to points on a lattice

I have a simple lattice / line manipulation: ...
7
votes
1answer
131 views

Mathematica Reference Book on Reliability Engineering?

Can anyone suggest a reference book titled “Reliability Engineering Using Mathematica” or similar that contains the version 9 or version 10 functionality ? Some topics/chapters I would be interested ...
7
votes
0answers
284 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: ...
6
votes
3answers
624 views

How to manipulate gauge theory in Mathematica?

I want to know if there is a way of typing into Mathematica an expression like the following, $$\epsilon^{\mu \nu \lambda} f^{abc} A^a_\mu A^b_\nu A^c_\lambda + g\epsilon^{\mu \nu \lambda} A^a_\mu ...
6
votes
2answers
249 views

Adjusting Density Plot Color Function for Diffraction Simulation

I'm trying to simulate Fraunhofer diffraction by a single slit using DensityPlot I run the code: ...
6
votes
1answer
618 views

Drawing a graph with specified edge lengths

I was wondering if it was possible to ask Mathematica to draw a graph provided some set of vertices: $(v_1, ..., v_N) \in V$ connected by $M$ edges $(e_1, ..., e_M) \in E$, where the length of each ...
6
votes
1answer
835 views

Interactive steam tables and phase diagrams in Mathematica

I teach an undergraduate course in Thermodynamics and I would love to use Mathematica to demonstrate the various engineering processes that involve the expansions and compressions of steam and common ...
5
votes
1answer
1k views

NDSolve, Schrödinger equation, and decaying solution

I am trying to solve a Schrödinger equation for a particle hitting a step potential using NDSolve in Mathematica. Here is my code: ...
4
votes
1answer
465 views

How to start simulating physical problems?

I'm quite new to Mathematica, I have version 9. I need to use it to simulate some physical problems. I know the equations (like Maxwell's equations and Newton's laws and so on), but I have no real ...
4
votes
1answer
498 views

Computing Slater determinants

I need to compute Slater determinants. I'm wondering if I would benefit from assigning each of my functions to a variable prior to computation. I'm working with Slater determinants, but my question ...
3
votes
1answer
463 views

How to change coordinates of a differential operator?

I'm doing a basic quantum mechanics problem and am trying to learn how to do it in Mathematica. Any help would be much appreciated. $\vec{L} = \vec{x} \times \vec{p}$ where $\vec{x}$ has ...
3
votes
1answer
141 views

Extending D for four-derivatives

I'm currently trying to consistently define rules for extending D[] to four-derivatives. As 'backend' I'm using the package TRACER (http://library.wolfram.com/infocenter/MathSource/2987/), which can ...
2
votes
2answers
293 views

Physics based Mathematica project ideas? [closed]

I am looking to make a physics based Mathematica project. Ideally the project would take around 12 hours, gathering any experimental data and analyse the findings. I'd have full access to university ...
2
votes
1answer
264 views

NDSolve with vector function

(Possible duplicate yet I still can't understand.) Basic 2D revolving around origin: ...
2
votes
1answer
77 views

Will I be able to use NDSolve, and then how

So I am completely new to Mathematica, so sorry if this is a dumb question. I have a set of 3 coupled nonlinear differential equations. They are (a,b,c,D,L constants): ...
2
votes
1answer
179 views

Calculate scalar potential from electric field

Is it possible for Mathematica to solve an equation like $\nabla f(\mathbf{r}) = - \mathbf{E}(\mathbf{r})$ for $f(\mathbf{r})$? I tried ...
2
votes
1answer
181 views

Animated Wave Propagation using Fourier & InverseFourier

This is a continuation off of previous help on the first part of my project: fourier issue arising from input miscommunication Now I want to go one step further in the current code. Here's the code ...
2
votes
1answer
167 views

Need more float precision

I have a Physics problem which huge and tiny numbers and Mathematica just gives me a speed of my particles which is the speed of light. Then $1/\sqrt{1-v^2/c^2}$ becomes singular. If I use smaller ...
2
votes
0answers
187 views

Visualising Special Relativity

Mathematica newbie learning by doing (or not so far, in this case). Problem: Special Relativity - consider two inertial frames $A$ & $A'$ in relative motion. At a time $t0$ as measured in $S$, ...
2
votes
0answers
64 views

Is it possible to use Gaussian cgs units in $Mathematica$ computations?

I was trying to do computations in Gaussian cgs units, and of course I failed due to dimensional issues. For instance, $q_1 q_2/r$ cannot be converted to $\mathrm{erg}$ since Gaussian system uses ...
2
votes
0answers
70 views

List of supported units in Mathematica 9 [duplicate]

Is there a list of supported units in Mathematica 9 documentation? I personal haven't found any; even the physical constants (newly supported as units in 9) can only be found in compatibility ...
1
vote
1answer
201 views

Finding 111 plane of Carbon Diamond

All, I looked at the example on the Mathematica Website with the Carbon Diamond Lattice. Example I am referring to I am wondering is there a way to highlight an individual plane such as the 111 or ...
1
vote
2answers
82 views

How to fit exponential function which is not converging

I performed an experiment where I measured diffusion in a lipid bilayer. I performed the measurement by fluorescently labeling some molecules in the bilayer, and the irradiating them with light ...
1
vote
1answer
117 views

Integral over squared Hermite polynomial

I would like to calculate the uncertainty of the nth Eigenstate of a 1-dim harmonic oscillator. To obtain the result I have to solve the integral $$\int_{-\infty}^{\infty} \psi^* x^2 \psi \:dx$$ ...
1
vote
1answer
179 views

Plotting equations of motion of a baseball

So I went through the physics of a baseball and I got the exact same equations as shown here on page 8. I input all of the same parameters into my code, and I don't get the same thing. Any idea ...
1
vote
2answers
257 views

Doing vector manipulations on Mathematica

This is hopefully a simpler version of this previous unanswered question of mine. Let me just focus on the two expressions $F_2^{(s)}$ and $F_3^{(s)}$ given in A.3 and A.4 of page 19 of this paper. ...
1
vote
1answer
56 views

Traces of products of Pauli matrices

Given a matrix $M$ of shape $2^L*2^L$, I would like to compute all the traces $\text{Tr}( M.(\sigma^{n_1}\otimes\sigma^{n_2}\otimes\ldots\otimes\sigma^{n_L})) $ for $n_1=1...4$, $n_2=1...4$, ..., ...
1
vote
2answers
127 views

Making mathematica do regulated integrals

Consider the integration, $\int _0 ^\infty dx\ x \tanh( \pi x) \sqrt {x^2 + a^2 } $ where $a$ is a real number. This integral is divergent. We note that an asymptotic expansion of the integrand ...
1
vote
2answers
163 views

Trying to graph trajectory function in Mathematica? Won't Graph?

The exercise is: define the trajectory function y(x) in Mathematica. Pick the initial speed (in meters per second) equal to 2 ...
1
vote
2answers
236 views

Inputting two arrays for a module in Mathematica

I am relatively new to the Mathematica enviroment and not sure where I am going wrong. I have evaluated the question and understand it, but dont know how to exactly create a module for it. The ...
1
vote
1answer
46 views

Operator operation

There are two basic operators r={x,y,z} and p=-I*h*{D[#,x] , D[#,y], D[#,z]} &. The angular momentum operator is defined as ...
1
vote
0answers
48 views

Solving for a charge distribution from a dipole moment [on hold]

I've been looking around but I haven't been able to find any way of solving this conceptually simple problem. In short I am trying to find the charge density in a dielectric in an external electric ...
1
vote
0answers
465 views

Kramers-Kronig Mathematica code

I'm trying to write Mathematica code to use Kramers-Kronig on a csv file with 2 columns. Column 1 is h(eV). It goes from 0 to 6, in increments of 0.1. Column 2 is alpha (cm^-1). For some reason, my ...
1
vote
0answers
119 views

Getting poles of a Gamma functions [duplicate]

Why do the following 2 sequences give different answers? n = 1.5 Series[Gamma[0.5 - n - x], {x, 0, 2}] Series[Gamma[-1 - x], {x, 0, 2}] (..clearly the output from the second expression is ...
0
votes
3answers
184 views

Find an equations of motion using Euler Eqution [closed]

I am a completely new to Mathematica, so my question and code may look silly. I need to find a equation of motion of a point particle of mass m moving in a potential V(x) = A abs[x]^n. (n=1,2,3,4,5,6. ...
0
votes
1answer
80 views

NDSolve finding solution when it shouldn't

NDSolve in mathematica drives me crazy and I'm seriously thinking about switching to Matlab because of strange bugs I run into. ...
0
votes
1answer
123 views

Feynrules -> FeynArts issue

When I try to use model files generated by FeynRules in FeynArts, I always get errors of this form Coupling definition in ...
0
votes
2answers
155 views

Reduce on equations involving integrals

Here's part of problem from a college physics text: A time-dependent force F = (8.00 i - 4.00 t j) N (where t is in seconds) is applied to a 2.00-kg object initially at rest. (a) At what time ...
0
votes
1answer
142 views

High quantum harmonic eigenfunctions?

How to obtain high quantum harmonic eigenfunctions? Everything works until, let say 65th eigenfunction, but for higher eigenfunctions values are too high. My code ...
0
votes
1answer
272 views

Circular Orbit Velocity in Vector Components

I'm trying to find out how to calculate the initial velocity needed to keep a spacecraft in a circular orbit around the Earth given its initial position and an initial angle theta in a Cartesian ...
0
votes
3answers
225 views

Differential equation of mass spring system with compliant stoppers

I would like to solve numerically the differential equation for the displacement x[t] of a mass m-spring ...
0
votes
1answer
116 views

Plotting results of numerical differential equation

I'm numerically solving the ODE equation $a = -kv$, i.e. $ x'' = -kx'$. sol = NDSolve[{y''[x] + 0.1 * y'[x] == 0, y[0] == 0, y'[0] == 10}, y, {x, 0, 100}] I need ...