Recent content by Feynmanfan

THanks for your comment but what I want to know (whether it exists or not) is how we can infer from the band structure that the fermi level is where it is and that the Be2Si is a metal.

Sorry Astronuc, that's the point of the article: no Be2Si is found in nature and it's predictions are base on ab initio calculations. It is a metal and this can be deduced from the band structure. Please help me interpret the band structure. The article says that it is a metal because of...

Dear friends, I'm having trouble understanding an article by M. Cohen and J. Corkill (Structural, bonding, and electronic properties of IIA-IV antifluorite compounds). In this article Be2Si (an imaginary compound) is shown to be a metal. The argument used is GROUP SYMMETRY :... group symmetry...

Dear friends, I followed your recommendations and took the GRE and sent my applications to many grad schools. Now it's time to wait for replies. The first one came 3 weeks ago from MIT. I have been admitted into the Physics Graduate Program. I haven't heard from UT yet. MIT is like a dream...

Thank you for your comments. Regarding the GRE, I took the Subject test while I was in Texas (because I was thinking of going back at that time). I didn't have time to prepare and my score was 880. Someone told me that the score was low for universities like Caltech or MIT. I don't know about...

Dear Physics friends, the time has come for me to decide what to do with my physics degree. I have asked a lot of people but in the end its me who has to take the decision. But I think I need your counseling. Let me tell you something about what I have done so far: I studied physics for 3...

Homework Statement I'm having nightmares with this problem, apparently simple (A&M Chapter 7 Prob 2). I have to show that a trigonal primitive lattice, depending on its angle, can represent fcc or bcc. This I kind of figured it out intuitively. But the serious problem is number b), where I...

Here's a physics student trying to perform the Belousov experiment, that is the chemical clock that changes its color from red to blue and viceversa. I've been able to "borrow" the following reactants: H2S04(sulfuric acid) 1,5M NaBr03(sodium bromate) 0.08M CH2(COOH)2(malonic acid)...

Here's a question my thermodynamics teacher was unable to answer. I present it to you and see where the flaw of my argument is. Is it possible to derive the 3rd law of thermodynamics from the 2nd law? Carnot's theorem (no other machine than Carnot's has maximum efficiency) tells us that...

I have some trouble with this electromagnetism problem: I need to transform the four-potential of a magnetic dipole at rest, in order to obtain it's value in a reference frame (I understand it's the Lab frame) where we see the dipole moving at v. I know what the magnetic vector potential is...

Thank you guys! After having read these threads I'll try to apply for UT Austin.

Hello! I'd like to ask your opinion about the University of Texas at Austin. As European student I'm considering applying for a TASSEP (TransAtlantic Science Student Exchange Program) and study my 4th year in physics in the US.(if selected for the program, of course!) I need to choose a...

I need to find out at what distance creates a magnetic monopole the same magnetic field as an electron with Bohr's magnetron magnetic momentum. I don't know how to calculate the field of a monopole. I know what an electric charge is; but a monopole? As a clue I've been given Dirac's...

How can I prove that the Hamiltonian commutes with the angular momentum operator? In spherical coordinates it is straightforward but I'd like to understand the physical meaning of it. Thanks.

Normalization of a wavefunction Let Phi be a wave function, Phi(x)= Integral of {exp(ikx) dk} going k from k1 to k2 I'm having trouble normalizing the wave function. I calculated the integral, then multiply by its conjugate and now I'm supposed to integrate again /Phi(x)/^2 in all...