Here is an intuitive way of reasoning through the problem. Consider the conventional unit cell of size a3 for the FCC lattice. Then the set ai you have mentioned are just primitive basis vectors for this lattice. Now -- mentally speaking -- subdivide the conventional cell into eight smaller...
really? with dr. yelton? i think i only attended one day of that outside the exams. anyway, say hi if you see me at the physics building. I'm usually just doing nothing in the computer lab around 11:45-12:50, before optics.
I have some confusion about what 'radiance' means as used in radiometry; specifically, I don't understand what it is a function of. For example: radiant energy is specified over some region, radiant energy density is specified at a point, radiant flux is specified across some surface...
It isn't such a bad idea to imagine your a great physicist, at least once in a while. It boosts your self-confidence and makes you feel better. But realizing your not so spectacular isn't such a bad thing either; certainly, it taught me some humility.
For the most part though, I like to think...
Okay, thanks guys. I'll cross my fingers, but I think I'll just start focusing for applying to the following school year. Personally, starting a year later doesn't bother me as long as I can do something fruitful in the meantime. Does anyone have any ideas?
I recommend the text A Course in Thermodynamics Vol. 1 by Joseph Kestin. It's a long winded and (in some parts) outdated book, but keep reading and you're almost certain to walk away with a better knowledge of the subject than the typical undergraduate books available. It would also serve as a...
Hi. I am sort of an idiot and only applied to one graduate school in physics, namely the University of Illinois at Urbana-Champaign. Most likely to do Condensed Matter, but I'm not completely sure. I just submitted the application today as a matter of fact. Anyway, I am obviously anxious because...
Singularities? I don't understand. The integrand is well-defined for all real values x and the integral almost certainly exists over any range. Sorry, I have not had a course in complex analysis.
A quantum mechanics problem calls for the reader to find the momentum space wave function of \Psi(x,0) = A/(x^2 + a^2) . But I do not know how to resolve the Fourier transform:
\Phi(p, 0) = \frac{1}{\sqrt{2 \pi \hbar}}\int_{-\infty}^\infty e^{-i p x/\hbar} \frac{A}{x^2+a^2}dx.
The...
I read through the derivation of bound and scattering states for a finite square well. The logic made sense to me, but I am not entirely sure how to accommodate an arbitrary initial wave function (with mean E < 0). Afterall, there are only a finite number of bound states. My guess was that the...
your right, sorry. i was hoping someone could recognize this as a special case of a more general problem or simply point out that the answer is unviable. but, I've looked it over more carefully, and i think it is. in any case, recapitulating what i did helps me understand it a little better.
The problem asks for the transmission coefficient for a wave packet with energy approximately E passing through a potential function with dirac delta wells of strength alpha at x = -a and x = +a. To solve the problem I split the region into the three obvious intervals [-inf, -a], [-a, a], and...
actually, there is no need for energy flow (or at least it is indistinguishable from a rest case). take any slice of the lever. it must have a balanced set of forces acting on it in either frame. thus, there will be no net energy flow into or out of the slice. more generally, we will not observe...