9 Questions 18 Answers 0 Followers
Questions related from Debajyoti Sarkar
We consider the Hamiltonian to be Hermitian to make energy eigenvalue real. But, say for some infinitesimal region we can't measure the energy. Can the Hamiltonian be non-hermitian in that case?
02 April 2015 8,708 10 View
Let's consider, I have an equation U(t2-t1) χ= σzχ. Here U represents the time evolution operator and χ is the spin state. Now if take log of both side, left side gives the Hamiltonian while the...
02 April 2015 804 2 View
Say I have an Hamiltonian H= A/(dt). Now we can write the infinitesimal time evolution operator as U(dt)= 1-iHdt. But for this case the result is U(dt)=1-iA+(iA)2 /2!....... Which implies that...
02 April 2015 2,677 8 View
The observed Lithium abundance is in disagreement with the standard big bang model. What are the possible solutions to the problem? How much the observations are reliable in this case? Is it...
30 March 2015 8,714 11 View
I need to find the eigenvalue of the operator of the form $\int dx k \vert x \rangle \langle x \vert$ ( x goes from -a to +a). It seems that the eigenvector is $\int dx c(x) \vert x \ rangle$....
29 March 2015 7,369 3 View
What is the method for finding the power spectrum from the distribution of density? Considering I have the distribution of density over a certain volume.
02 May 2014 4,087 2 View
I have seen different estimations of photon diffusion time in different papers (30000 to a million years). There are many different mean free paths used. I want to know if these results are just...
02 May 2014 3,900 8 View
In the case of general relativity the change in coordinate can give rise to fictitious perturbations, for which we can use gauge invariant variables or we can also choose a specific gauge. My...
16 April 2014 3,671 3 View
It was shown by Tolmann that if the cosmological constant is zero then no minimum radius of universe exists (rate of expansion becomes negative infinite at R=0). Now dark energy gives a...
09 August 2013 8,022 6 View
