Recent content by gre_abandon

I know how saturation spectroscopy works but I am not sure which peaks you are referring by crossover peaks.

Smear the solution onto a glass substrate and take an image under scanning electron microscope.

In Schrodinger's picture the state ket undergoes unitary time evolution dictated by Schrodinger equation. The exepctation value of a operator A is $$ \langle \psi | U A U^\dagger | \psi \rangle $$. In Heissenberg's picture the operator varies with time and is given by $$ A' = U A U^\dagger $$...

You can measure magnetic field through Hall effect. Suppose you have a piece of conductor of square shape with the four edges labeled A,B,C,D. If you apply a voltage across A,C there be a current. Now if you place this piece of material into magnetic field which will cause the charges in the...

Yes but SU(2) is not equivalent with SO(3). In the representation of Bloch vector the global phase is missing,

No, the state of a spin 1/2 particle is a vector in 2d complex vector space rather than a vector in 3d real space.

You know for a spin 1/2 particle its state is represented by a vector in C^2 and measurement is modeled as a projection. I am not sure what you are really asking but I think reading a book on quantum computation will help clarify your question. Generally any book on quantum computation will talk...

I see your point. I treated the number as a one-by-one matrix because I am not sure whether it is really a scalar times a identity matrix (not clear from the statement of the problem). Except this point, everything is fine.

Simply speaking $$ trace(\langle \Psi | \Phi \rangle) = \langle \Psi | \Phi \rangle = \sum_n \langle \Psi | n\rangle \langle n | \Phi \rangle = trace(|\Psi\rangle\langle\Phi|)$$

On wikipedia and my textbook the only constraint on the demon is that the demon should hold non-negative energy while in my opinion there also should be an upper bound as well for demon energy. And the energy fluctuation of the system is between E_demon_min and E_demon_max. If the energy...

I simulated a microcanonical ensemble of 10 ideal gas particles in one dimension and yielded the expected normal distribution of velocities. However, I still did not get how the algorithm works. The demon has non-negative energy content and the demon together with the system constitutes a closed...

Yes, these theorems both only apply to closed system. Speaking of open quantum system, we usually consider the system we are interested in and the surroundings together as a whole. The time evolution of the whole system, which is unitary, can be written as $$ \mathcal{H^{sys}}\otimes...

The system we dealt with in quantum mechanics is usually a closed system. Sometimes we also study open quantum systems but still the system together with the surroundings constitutes a larger CLOSED system. And Schrodinger equation only applies to a closed system. You are correct on this point...