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

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0
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0answers
157 views

Solving for a Transfer Matrix

I am currently working on a program that will solve a transfer matrix and extract several elements. Particularly, the transfer matrix is characterized by four elements in a ...
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0answers
94 views

Maxwell propagator problem 2D [closed]

Hi folks I`m trying to turn certain matlab code to mathematica but for some reason it doesnt really want to do it could you please assist me a bit. Thanks The matlab code is as follows: ...
0
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1answer
91 views

Plotting and Analysing derivatives of solution of differential equation [closed]

Using NDSolve I found the solution for the differential equation that governs the dynamics of a simple pendulum. How do I plot the derivatives of the solution? Also, I would like to find the ...
1
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0answers
83 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
2answers
521 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 ...
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0answers
58 views

SetDelayed::write is Protected error on Linux not PC

I have 2 computers, a PC and an Ubuntu computer both with Mathematica 10. I am running the exact file with the exact support files on both computers, but just on the Ubuntu I get the following error ...
1
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0answers
163 views

Finding the point of best focus for a ball lens [closed]

This is my project (simulation): A set of parallel rays goes trough a ball lens (circular lens). Because of spherical aberration, refracted rays will not meet in a single point. Find the distance ...
12
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2answers
284 views

Pull out scalars from NonCommutativeMultiply in commutator of SU2 spin algebra

I am trying to work on spin chains in Mathematica. That is, N spin-1/2 on a one-dimensional lattice with periodic boundary condition (N+1=1). I need therefore the SU2 spin algebra $S_z, S_+, S_-$ with ...
11
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2answers
564 views

How to calculate position from 3 dimensional acceleration data?

I discussed this problem yesterday with Pickett here. We concluded that the best solution may be just Interpolate and then ...
2
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1answer
158 views

2D Fourier transform of a few (4) disjoint discs on a plane

I'd really appreciate some advice. Short Version I'm trying to calculate the following $$ ...
8
votes
1answer
347 views

Calculate inertia tensors

Moments of inertia and inertia tensors are well-known characteristics of rigid bodies in physics and applied mathematics. How to calculate them in Mathematica? Is possible to use regions which was ...
5
votes
1answer
472 views

NDSolve and Piecewise functions

I want to clarify upfront, This is not a please help me get the answer to my homework question. I know what I need to do I just do not know how to get mathematica to do it. I am working on an ...
8
votes
3answers
444 views

Biot-Savart Law/Magnetostatics Solution

I am working on solving the Biot-Savart Law equation for the magnetic field around a charged ring of uniform current density. The expression that Mathematica gives is rather nasty, as expected. Notice ...
7
votes
1answer
369 views

How to draw quantum circuit with mathematica?

How to draw quantum circuit as the following one with mathematica? I only find the quantum package which is designed for MMA 7.0 as the author said. But the version of my Mathematica is 9.0 and when ...
5
votes
1answer
519 views

How to solve fluid flow problem based on Navier-Stokes equations?

Does anyone know or can provide any examples how fluid flow problem can be formulated and solved in Wolfram Language? Simplest cases of 1D or 2D flows based on Navier-Stokes equations or even their ...
20
votes
3answers
1k views

Convert spectral distribution to RGB color

Presume I have a spectrum as a function of wavelength (an example being the blackbody spectrum): I want to convert that to a single RGB color to display on-screen, i.e. the "color" of that object ...
8
votes
3answers
177 views

Substituting values in 3j symbols

I believe these three expressions should give the same answer of -1/Sqrt[3], but the first gives +1/Sqrt[3] whereas the second ...
3
votes
1answer
135 views

Interpolation function rejected by ParametricPlot3D

I was playing around with the bouncing ball example, and decided to make a 3d version. I decided to use ParametricPlot3D for a simple independent 3D ...
1
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0answers
140 views

Solving PDEs with complicated boundary conditions

The system I'm trying to solve is $$\nabla^2 C_{(r,\theta)} =0$$ $$C_{(\infty,\theta)}=C_0$$ $$ [ \frac{\partial C_{(r,\theta)}}{\partial r} \cos(\theta)+\frac{1}{r}\frac{\partial ...
1
vote
1answer
61 views

How to make a discretized NMinimize more precise

I am using Mathematica for physics research and I want to minimize a Hamiltonian equation with respect to two variables (I have also discretized the problem). I have a single constraint. When I plot ...
0
votes
1answer
107 views

Help with Computation-heavy triple integration

I'm Trying to use Mathematica to symbolically integrate a function with respect to x, y, and z. For some reason, this computation either takes about, 60s and returns the input, or takes many hours ...
1
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0answers
88 views

Help wanted in evaluating an integral

Trying to evaluate an integral. To be specific, I'm trying to find the expectation value of $x^2$ for the ground state of hydrogen. Here is the code I used: ...
0
votes
1answer
253 views

Solving for the time-evolution operator in a periodically driven system

I am looking at the Hamiltonian $$H(t)=\begin{pmatrix} 0 & e^{i\Omega t}\\ e^{-i\Omega t}& 0\end{pmatrix}$$ I am trying to solve for the unitary operator $U(t,0)=\mathcal{T}\exp(-i\int_0^t ...
19
votes
2answers
2k views

Animation of double pendulum

Sadly, I am a completely newbie. I am studying Physics and in our theoretical physics class we got the task to solve the double pendulum using Mathematica. We just got the program, but no introduction ...
3
votes
1answer
131 views

How to simulate the 1-D motion of a particle under constant acceleration? [duplicate]

I am trying to represent the position of an object under freefall, but am completely lost. Here is my attempt so far: ...
2
votes
1answer
385 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
158 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 ...
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vote
1answer
121 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 ...
10
votes
3answers
516 views

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

I have a simple lattice / line manipulation: ...
1
vote
2answers
167 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 ...
0
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0answers
263 views

Boundary Value Problem- using NDSolve or another method

I am trying to solve a set of coupled partial differential equations, with defined boundary conditions using mathematica. Here are the equations and the boundary conditions. ...
2
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0answers
341 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
2answers
488 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 ...
0
votes
0answers
287 views

How to obtain differential equations of motion using Lagrangian dynamics?

I'm confused to find a set of differential equations of motion of a pair of masses, m1 and m2 joined by a spring of constant ...
14
votes
3answers
717 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 ...
8
votes
1answer
283 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 ...
2
votes
2answers
1k 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 ...
1
vote
1answer
214 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
351 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 ...
2
votes
0answers
284 views

Crank-Nicolson scheme for the Schrödinger equation

I am trying to solve the 1-D Schrödinger equation with the Crank-Nicholson method. I use the atomic units: time < 10^-14 => 413 a.u.t. length 30 * 10^-9 m => 567 Bohr radii ...
1
vote
1answer
261 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 ...
2
votes
1answer
86 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): ...
9
votes
1answer
724 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: ...
2
votes
1answer
359 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 ...
1
vote
1answer
292 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 ...
2
votes
2answers
890 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 ...
2
votes
0answers
115 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 ...
0
votes
3answers
403 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 ...
3
votes
1answer
485 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 ...
0
votes
1answer
153 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. ...