Recent content by Thomas Brady

So I am aware the charge conjugation operator changes the sign of all internal quantum numbers. But I was wondering how it acts on a state such as ## \left|\pi^{+} \pi^{-} \right>## when the individual ##\pi's## are not eigenstates of C. I believe the combination of the ##\pi's## has eigenvalue...

P.S. I used n.u. for this

So, I have to show that in the non-relativistic limit the lower two components of the positive energy solutions to the Dirac equation are smaller than the upper two components by a factor of ##\beta##. I started with the spinor $$\psi = \begin{pmatrix} \phi \\ \frac {\vec \sigma \cdot \vec p}...

I am given a hamiltonian for a two electron system $$\hat H_2 = \hat H_1 \otimes \mathbb {I} + \mathbb {I} \otimes \hat H_1$$ and I already know ##\hat H_1## which is my single electron Hamiltonian. Now I am applying this to my two electron system. I know very little about the tensor product...

Right, and with the problem I was given it does not appear to specify which state it is in.

So, essentially I cannot determine the probabilities, with the given information

I'm pretty new to quantum, so I'm pretty sure I'm missing something basic here. I've got a 4x4 Hamiltonian with eigenkets $$\psi_{U} = 1/(\sqrt 2) (\psi_{1up} \pm \psi_{2up})$$ and $$\psi_{D} = 1/(\sqrt 2) (\psi_{1down} \pm \psi_{2down})$$ The only difference between the two states is the spin...

Homework Statement Heat engines at negative temperatures. Consider using two heat reservoirs to run an engine (analogous to the Carnot cycle of chapter 3), but specify that both temperatures, T_hot and T_cold, are negative temperatures. The engine is to run reversibly. (a) If the engine is to...

Okay, valid points. So I've heard of the optional essay you may write for grad school discussing weaknesses in your application. Now this may be a bit personal, but basically, the main reason for the weaknesses in my application (i.e. the NP and some other not great grades) is an addiction to...

1) Nothing I can do other than try to pass just wondering 2) I have done well in other GE courses but also why would a grad school care so much about that if I am going there to pursue specific research interests

So i am currently going into my third year in the fall and this summer I'm taking a few courses and finally got my first opportunity to participate in some research. Problem is there is a good chance I will get a NP (not pass) in a GE class I am taking. I am going to a UC so an NP does not...

Pretty broad question, but to be more specific, in my case I'm currently in my 2nd year of undergrad going for physics and electrical engineering at ucsb. I didnt perform too well up until now with a cumulative of 3.2, so if i were to raise my gpa up to around 3.5-3.6 by the time i graduate what...