Recent content by barcodeIIIII

Homework Statement The unitary time evolution of the density operator is given by $$\rho(t)=\textrm{exp}(-\frac{i}{\hbar}Ht)\,\rho_0 \,\textrm{exp}(\frac{i}{\hbar}Ht)$$ General definition of entropy is $$S=-k_B\,Tr\,\{\rho(t) ln \rho(t)\}$$ Proof: $$\frac{dS}{dt}=0$$ Homework Equations I am not...

Hi, Incand, thank you for your reply! Yes, I do have problems with submitting assignment before deadlines(specially in QM). Usually I will take 4 courses and each course has assignment every 2 weeks, each assignment is about 5 to 8 questions long, I also have pre labs and lab reports due as...

I am an undergraduate student (moving to last year this September). I found out that on my third year, I needed much more time to work on assignments and exam questions compared to 2nd year. I think I am kind of slow and a little bit worried in the last year that things might get out of...