Recent content by White Ink

Thanks, malawi_glenn & CompuChip. So in the case of the Coulomb gauge, would it be correct to say that it is acceptable to set divA = 0 because whether or not we consider the components of A as being (spatially) constant, we do not lose the E generated by a time-varying A? And, following...

I posted this here because gauges seem to play a far more significant role in modern physics than in classical (bar the obvious exceptions). I want to ask a general question: I've been reading about gauges and gauges theories recently, but nowhere have I actually found solid justification...

No. That was just something I wrote based on your agreement with the comment after the asterisk (something which we have now cleared up). Unfortunately I don't have time to write a longer reply right now, I'm in a bit of a rush.

Ooops, I feel stupid now. I forgot about the metric coefficients and took my volume element to be drd\theta . At least I won't be making that mistake again. Thanks.

Now that one beats me. I can't see where an additional r^{2} would come from.

I know exactly what you mean (integrating in the \theta & \phi directions becomes equivalent to multiplying to constant in front of the integration with respect to r by 2\pi^{2}, since the wavefunction is independent of those two variables). I read over the question too quickly. Thank you for...

The two statements you seem to be backing here represent a contradiction in your logic in my view. Just because one observer does not have proof of something existing, this does not mean that that something does not exist (see next paragraph). In essence, if you agree with the point I made...

\int^{\infty}_{0}\left|\Psi(r)\right|^{2}dr = 1\frac{C^{2}}{4\pi}\int^{\infty}_{0}e^{\frac{-2r}{a_{0}}}dr = 1 u = \frac{2r}{a_{0}} du = \frac{2}{a_{0}}dr dr = \frac{a_{0}}{2}du\frac{C^{2}}{4\pi}\frac{a_{0}}{2}\int^{\infty}_{0}e^{-u}du = 1 Using: \int^{\infty}_{0}x^{n}e^{-x}dx = n...

Homework Statement A hydrogen atom in the ground state can be described by the following wavefunction: \Psi(r) = \frac{C}{\sqrt{4\pi}}e^{- \frac{r}{a_{0}}} Normalise this wavefunction. The Attempt at a Solution I did this and got: C = \sqrt{\frac{8\pi}{a_{0}}} I have no way of checking...

Your first point is fair as a stand alone comment (that is to say, I agree with it). But, surely for the photon to be carrying any such information in the first place (irregardless of whether or not an observer can make sense of that information) this implies (at least in my mind) the...

I remember seeing in the NOVA TV version of Brian Greene's The Elegant Universe that they gave the scale of a string as being the size of a typical tree on Earth if the entire solar system were to represent an atom. So directly, yes, it would seem that string theory is untestable (which is why...

I am by no means an expert in string theory, but as far as I understand it, branes are simply strings with vast amounts of energy (and are able to increase in size accordingly). Strings are confined to certain branes based on whether of not the strings themselves are open ended or closed...

Two quick questions: 1. Is this 'overlap integral' the convolution of the wavefunctions in each potential? 2. Is taking this 'overlap integral' in such a situation generally the way to tackle problems such as this?

Homework Statement Write a function that prompts the user to enter a year and that returns a 1 if the entered year is a leap year, and a 0 otherwise. A year is a leap year if it is divisible by 4. In general, a year is not a leap year if it is divisible by 100, unless of course it is...

This is basically the same as what HallsofIvy just suggested: Perform Gaussian Elimination on the matrix formed by combining the two vectors. Use the fact that the pivot columns of a matrix are linearly independent.