Recent content by WraithM

Of course! I have to add the condition that the operators are linear! Silly me :) Thanks!

I'm curious if there's a chain rule for the commutator (I'll explain what I mean) just like there's a product rule ([AB,C]). So, say you have an operator, which can be expressed in terms of another operator, and we know the commutation relationship between x and another operator, y. I'll call...

Thank you for the replies! I have it stored in a 6D array. I've considered the way that phyzguy suggested. It seems that method would take a very long time. I've got a grid of a 10^6 points on it, but this method would be extremely easy to implement. It'd be like 5 - 6 lines of code in Matlab...

So, I'm writing a program in matlab. I have a function of six variables, say f(x1,x2,x3,x4,x5,x6). I want to integrate over x4, x5, and x6 numerically. f is defined over a 10 sided 6-cube of points. I also want to integrate over the whole cube. So I want, F(x_1, x_2, x_3) = \int\int\int...

Thanks, that actually completely answers my question. Forums turn people into internet tough guys. It's all good :)

Calm down.

I know the definitions of both. I was looking for the connection between the two. I fully understand that they're different ideas. Perhaps I didn't make myself clear in the question, but I meant how is the geometry related to thermodynamics? As I said, is it possible for a closed geometry to be...

"Open" and "closed" in the geometrical sense vs the thermodynamic sense Perhaps this is a silly question, but what is the relationship between the words "open" and "closed" in the geometrical sense (open, flat, closed universes) and in the thermodynamic sense (open and closed systems) in the...

Thank you elibj123! Your method worked perfectly. I replicated my results in Mathematica, and my results in C almost perfectly fit the Mathematica curve.

Actually, this could be in C++ too. C or C++ works.

I want to write a program in C that's going to solve 3 second order differential equations, and I have little to no experience in solving differential equations in C (however, I know C well enough). I'm having a bit of trouble. First of all, I don't really know what method I'm going to use to...

Lol, I was doing the divergence wrong, as I thought. I was being stupid. \nabla \cdot E = \frac{1}{r^2} \frac{d(r^2 E)}{dr} :/ integrate and you get: E = \frac{\rho r}{3 \epsilon_0} replace rho E = \frac{Q}{4 \pi \epsilon_0 r^2} k, good. I'm not crazy, just doing it wrong.

I don't really know much about serious business electrostatics. I've only taken the AP Physics C E&M exam (using the integral form), but I was looking at wikipedia and I was curious about the differential form of Gauss' Law. I don't understand what I'm doing wrong with this. I'm trying to...

Could you show me what you mean? (with math. I know calc and a good deal of classical mechanics, so I'll understand.)

I saw a teacher today with a piece of chalk tied to the end of a string (for drawing circles and such on a chalk board) swing the string around, and the string wrapped around his finger and the string became shorter until there was no more string left. His finger was pointed parallel to the...