yevgeny

And what if he is still waiting that someone will answer the questions he posed here? :whistle:

They are observables. You can measure anyone of them.

Hi! Unfortunately, I don't know much about physics programs in the US. Maybe you can use this to get some information: http://www.phds.org/rankings/getWeights.php?d=25 Yevgeny

I applied to Harvard, Princeton, Stanford, MIT, Caltech, and Cornell. I have been admitted to all of them. I decided to go to Harvard. ;)

I have been admitted to all places which I applied to :)

This is OK. In the limit of dq -> 0, k' becomes INFINITE. We all know this: take a long spring (1 m) so that you can easily stretch it by 10 cm. Then take a small piece of that spring (1 cm). It will be 100 times harder to stretch it by 10 cm. This is wrong. Which body are you considering? If you are considering the spring as a whole, then you shouldn't take into account the force applied by the string itself. Rather you should take into account the force applied by the roof, which you should somehow calculate. This is also wrong. The mass is not distributed uniformly along the stretched spring: the sping is stretched more at the top than at the bottom, so that the center of mass is lower than half the length.

It does not depend on the problem. By specifying that Sx = S, a full quantum-mechanical description of the spin is given. The calculation is correct even if the environment is different along y and z axes.

Energy per particle: u® = A/R^n + (kq^2/R)*sum[(-1)^n / n] where the summation is from 1 to infinity. The sum equals -ln2. Why specifically are you worried about it?

Doesn't the ENERGY of the electromagnetic field affect g?

Two of my friends gave me an answer to the original question. Moshe G. answered that looking at the time-reversed picture shows that the magnetization in both directions MUST BE THE SAME (when the direction of time is reversed, the directions of the magnetic field and the magnetization are reversed, while the crystal remains unchanged; and it is known that the relevant laws of physics are symmetric in time). Vadim K. answered that looking at the mirror reflection, with the mirror perpendicular to the line of atoms, also shows that the magnetization in both directions MUST BE THE SAME (in the mirror, the direction of the crystal is reversed, but the magnetic field and the magnetization keep their directions; and it is known that the relevant laws of physics are symmetric under mirror reflection). I added then that if the mirror is parallel to the line of atoms, it also proves this statement in a similar way. So simple! [banana]

Help - I think this is the right place for it. David Bohm - what exactly? I haven't read the "The Physics of tao"... What are your plans in physics, by the way? And what are you doing now? Yevgeny.

Dear Maria/Mihaela/Licorna (why so many names? :shy:) , What happened on my real GRE (including the results) is described in the topic "My GRE": http://www.TestMagic.com/forum/topic.asp?TOPIC_ID=8875 In 3 words: it was OK! As to the admission decisions, it's too early yet for most of them, but I have first signs of success. Hope you study well and answer all my questions here... :) Best regards Yevgeny

In empty space, there is a system of coordinates (t,x,y,z) in which the fundamental tensor equals: g = diag(1,-1,-1,-1) How will it be modified if a uniform electric field E in the direction of the x axis is added?

The official one is here: ftp://ftp.ets.org/pub/gre/Physics.pdf :drunk:

I found out that ecm was right about this (which is not really surprising about ecm :D). See here: http://curious.astro.cornell.edu/question.php?number=575