Recent content by Gravitino

I think i found my mistake: c^2 d\tau^2 = - ds^2

Could someone, please, explain me, the conflict in the stress-energy tensor units. So for the perfect fluid we have: T_{\mu\nu} = pg_{\mu\nu} + (\rho + \frac{p}{c^2})u_{\mu}u_{\nu} But on the other hand u_{\mu} = g_{\mu\nu}u^{\nu}. Now, in the comoving frame u^{\nu} =...

I was looking for a space time metric that describes the INTERIOR of spherically symmetric rotating stars. However, wherever I look it is always the metric for an exterior of "slowly rotating star" (frame dragging effect) or something similar to it but always the metric AROUND the object...

What about placing WMAP as a tattoo? You could also use a trap of neutron star near black hole. Or a funny picture that quarks want to escape from each other, but strong force does not allow it (confinement). One can find many ideas of this type.

I am guessing that the quantum consideration gave wrong result, the fact that the relative distance actually does not vary from 0 to infinity in phase space in classical universe gave probably a weird result...

[SOLVED] Equipartition Theorem 1. Kerson Huang, P 7.2: Consider a classical system of N noninteracting diatomic molecules in a box of volume V at temperature T. The Hamiltonian for a single molecule is taken to be H=\frac{1}{2m}(\vec{p_1}^2+\vec{p_2}^2)...

Thanks! :approve:

Thanks! I got it!

Net torque about center of pulley, you are right. For the first method, as i explained above, \tau=F_{net}R and F_{net}=M_1g-M_2g\sin\theta. In the second one, M_1\sin\theta g-T_1=M_1a -M_2\sin\theta g+T_2=M_2a and the answers stiull do not match.

Thanks. But i have still doubt. The first solution states that the net torque about the center of pulley, is just due to the external forces. They are the one which rotate the pulley. And Obviously, \tau=F_{net}R. And external forces are just gravity.

Two blocks of masses M_1 and M_2 passes through a pulley (See the Fig. attached.). Assuming the friction between block and the incline is zero, and neglecting the mass of string find the net torque about the center of mass of the pulley. I solved this problem with two different ways. The...

You are getting twice of the value, because you are neglecting the rotational motion of the hoops. The answer you got (twice value) is in the case when hoops are pointlike.

Thanks a lot for nice explanation. :)

I would like to ask the meaning of three pont correlation function if someone knows. It deals with initial perturbations in inflationary cosmology.