Recent content by raymo39

Its been a while since I've done this stuff, and I don't have a text handy. I know that for sets, intersection distributes over union, I don't remember if the same will hold for vector spaces over addition? for example does A \cap (B + C) = A \cap B + A \cap C

I agree, my post was in reply to the original poster. Guess i was late to the party

not necessarily, you need to also consider that this is only true if A and B are compatible observables, and it is only a matrix element if |1> and |2> are basis vectors of those same compatible observables.

So I definitely believe that the continuity of the Dirac equation holds, there is one thing that annoys me, which is that c \alpha . (-i \hbar \nabla \psi ) = c (i \hbar \nabla \psi^\dagger ) . \alpha from the first part of the Dirac Hamiltonian because the momentum operator should be...

One of the key points is understanding that acceleration doesn't just mean an increase in total velocity of the system, but changing direction of velocity is also acceleration. Consider circular motion in a 2d plane, like a ball on a string rotating at some constant rate (constant rpm) although...

As for the graviton thing. They are required only by quantum field theory, not by general relativity

Special relativity only describes motion with constant velocity. As soon as things start to curve or accelerate it falls apart. Which is what happens for most of the experimental evidence provided. Now, brb. I've got to (ironically) go to my GR lecture.

Possibly the most famous example originally was the orbit of Mercury around the Sun. Newtonian gravitation (NG) can't fully describe the orbit, General relativity can. Other than that, we have gravitational lensing, which is really cool to see, not at all predicted by NG, black holes aren't in...

Recently heard about the Schiff conjecture saying that any reasonable theory of gravitation should adhere to the ideas of EEP and UFF. I realize that this isn't a "strong" idea (only a conjecture after all), but to anyones understanding, does either loop quantum gravity or m-theory appear to...

the power of the exponential describes the direction of the evolution. here what you have is a solution that either describes a particle traveling in the positive or negative x direction. This is fine, because there is no confining potential, so the solution only travels one way through space...

?? it doesn't seem too simple, first its non separable non linear, but it is only first order. not quite sure what the post is for

as for an experiment, well you would need a box of some sort with water inside, where you can carefully control the temperature and pressure, then by adjusting both to the required points, you should be able to see water go from liquid to solid to gas and back to liquid, only making slight...

the proof of the riemann hypothesis is pretty interesting, although at first glance I'm not sure about one of his derivatives, and there seems to be a lot of assumptions...

Using the many body wavefunction is what I am after, as for QFT, i can pick that up from the basics of the Heisenberg picture and extend what i know there. thank you for this.

Hey guys, im currently doing some stuff on bec's and was wondering if there were any good textbooks out there in general to help be understand annihilation and creation operators, s wave scattering, Hamiltonians of dilute BEC's, Gross-Pitaevskii equation and so forth.