Recent content by K8181

Can someone please explain why an excited electron in an atom decays to the ground state, if energy eigenstates are stationary states.

I guess my confusion is...why is the particle still in the singlet state once the measurement of S1z has been carried out?

I found the problem in a book, and it says that the first observer is trained to measure particle one, and the second is trained to measure particle two. I don't think distinguishing between them is the crux of the problem. I am more concerned about eigenstates of angular momentum and that...

I have a hypothetical situation that I am trying to work through... Say there are two spin 1/2 particles, and the system is known to be in a total spin state of Stot=0. An observer comes along and determines the first particle to have a spin component (S1z) of hbar/2. Now say another...

From what I have deduced, I think the culprit is parity. Could you explain what you know about parity? I have always found it a mysterious concept.

For anyone reading this thread, that link was just about using LaTex for math symbols...I still REALLY need help with this problem! :biggrin:

Fantastic! I am already familiar with LaTex.

I just started a class in particle physics this semester, and I really need help on one of our first homework problems. We are supposed to show that while the following decays are allowed: roe(+) --> pi(0)pi(+) roe(-) --> pi(0)pi(-) roe(0) --> pi(+)pi(-) the following decay is not...

Isn't that backwards...? I thought a uranium nucleus should have a mass greater than the sum of its parts, since it is heavier than iron and thus "over the hump" on the curve of binding energy? No?

Wow! Thank you for a great answer. That clears up a lot of misunderstanding I had. :smile:

I have a question about the true meaning of E=mc^2. For starters, a certain amount of mass (m) can be converted into an amount of energy (mc^2), or vice versa. For example, two antiparticles can annihilate and leave only energy behind. So it is mass-energy that is a conserved quantity, not...

This thread has greatly helped me clarify my question. I am starting a new thread that is more to the point. Feel free to offer more insight there...and thanks for all the help. K

So is it possible for a particle to have inertial mass and gravitational mass that are not equal? I am recalling Einstein's equivalence principle, but maybe I am missing some information? I am very curious about this.

ps The book is Modern Physics for Scientists and Engineers by John R. Taylor and Chris D. Zafiratos.

Thanks for the website, it was very helpful and I think I am understanding this better. But I am still a little bothered... Consider a case of spontaneous fission. Before the split, the forms of mass-energy are the rest masses of the constituent particles, and the potential energy. After...