Recent content by Simon_Tyler

Of course it's possible to modify (and there is NO NEED TO SHOUT!) Just use a Do[] loop or a Table[] construction etc... For example: Clear[k, \[Kappa], a, b, V, \[Sigma], T, g] \[Sigma] = 1; a = 0.1; V = 3; \[Kappa] = Sqrt[V] - k*k; T = Abs[(16*k*k*\[Kappa]*\[Kappa]* Exp[-2*I*k*...

Hi lpetrich, it's always good to read your updates. You probably already know about this, but the symbolic manipulation program FORM has been used to calculate a huge number of invariants, Casimirs etc... http://arxiv.org/abs/hep-ph/9802376...

There's always the classic Xfig (http://en.wikipedia.org/wiki/Xfig)

Here's a quick hack polyForm[poly_, var_] := Module[{coeffs = CoefficientRules[poly, var] // Sort}, Interpretation[Row[Table[Row[{"(", coeff[[2]], ")", w^coeff[[1, 1]] /. 1 -> ""}], {coeff, coeffs}], "+"], poly]] Then theFunction = -2 + w^3 (-9 - 3...

You're right about jinc. I thought using the initial conditions would be ok, but I guess I didn't think about it enough! jinc should be constructed out of the forward moving components of the wave on the incident side of barrier. So I guess you need to perform a Fourier decomposition on a...

See the wiki article http://en.wikipedia.org/wiki/Quantum_tunneling The easiest way is to approximate the transmission coefficient T with the WKB approximation, then for any 1D potential V(X) T = 1- R = \frac{e^{-2\int_{x_1}^{x_2} dx \sqrt{\frac{2m}{\hbar^2} \left( V(x) - E \right)}}}{...

An interesting question (and well asked). Unfortunately, I don't have a good answer for you. If you use Trace[ NDSolve[...], TraceInternals->True], then you can see that NDSolve is trying the shooting method when it all goes wrong. However, I'm not sure what exactly is going wrong nor how to...

Just to complement what Qgravity posted: The standard reference on harmonic superspace (the place where the most general explicit N=2 SUSY theories can be studied and quantized) is Harmonic superspace by A.S. Galperin, E.A. Ivanov, V.I. Ogievetsky, E.S. Sokatchev. The first couple of...

Bill_K gave the answer for what the notation means. As for references, you can start with Wikipedia. The SU(5) model is known as the Georgi–Glashow model and is a simple example of a GUT. Probably the best intro textbook for this topic is Georgi's Lie Algebras In Particle Physics, where both...

Yeah, Leonid's performance tuning tips are good (like all of his answers - and his book!). I've sent you an invite for the new Mathematica.StackExchange site, which is currently in private beta. If you have any questions about optimizing aspects of your code, this is currently the place to...

Have you tried just using compilation to C in both Mathematica and Python? http://reference.wolfram.com/mathematica/Compile/tutorial/CompilationTarget.html http://docs.cython.org/src/quickstart/overview.html The generated C code can sometimes be almost as fast or faster than a hand coded...

I don't think that Numerov's method is built into Mathematica. So you have two options. 1) Just program a numerical solver using loops like you would in C++. Using Compile[] with the CompilationTarget -> "C" option will help speed it up. 2) Write a NDSolve Method plugin...

Hey lpetrich, I don't have much to say about your recent posts and work, since it's out of my range of experience and I don't have time to study it at the moment. So I'll just say that it sounds good and keep going!

It's a strange choice to make, since it's not in the range that you were numerically integrating over, but Mathematica seems to be able to handle it. Of course, from the point of view of the analytic solution, there is no problem. However, most numerical integrators would not be happy with...

I forgot to mention that the reiterate, as it stands, is simple enough that you can get an analytic solution. See the second code block in my first post. This might be a preferable option for you...