Recent content by Lakshya

Thanks for your reply. BTW, what is Weinberg's k' for different cases? It creates many different problems as I pointed out. Please clarify it also. Does his k' has anything necessarily to do with his previously defined standard momentum? If yes, then what if p and p' belong to the same class...

Weinberg in his 1st book on QFT writes in the paragraph containing 2.5.12 that we may choose the states with standard momentum to be orthonormal. Isn't that just true because the states with any momentum are chosen to be orthonormal by the usual orthonormalization process of quantum mechanics...

1. By definition of an ideal gas, the internal energy is independent of volume and dependent on Temperature. This is usually visualized as there is no interaction between the particles until the collide with each other. The internal energy is sum of internal KE and internal PE. The internal KE...

Exactly that's what I am trying to point out there. That there need not be a |c,d>. So, if |c,d> need not occur. Now consider this: There is a complete, commuting set of 'r' observables all of which have only continuous eigenvalues and no discrete eigenvalues. Now, it can happen that an...

If you go through the entire spectrum of comments, we settled on the issue that there is no good reason for |c,d> to occur. Why can't it be missing? All these developments are clearly indicated in the edited question which I posted above solid line. There is no second question. I don't know...

"Completeness" of eigenvectors in a complete, commuting set Hi guys, I asked this question on Physics Stack Exchange many days ago and even after substantial discussions and revisions, this has remain unanswered. This is...

According to me, you should first of all go through the first volume of Landau alongside a bit of Linear Algebra and Analysis. Then, do some QM from Sakurai alongside some more Analysis and Topology. Also, do some Special Relativity from second volume of Landau and some other books like Schutz...

I would request the experts out there to just show the slightest way, that would be much grateful. Or mods please transfer this thread to some location where this might be suitable (maybe in astrophysics section?).

Thank you very much. :)

Hi, I am currently enjoying my vacations and joining my UG course late this July. The institute I am joining doesn't offer any Astronomy and Astrophysics course but I am pretty much interested in it. So, I want some guidance and materials on how to start Astronomy and Astrophysics self...

What is the proof that the total rate at which radiation is emitted by a black-body radiator is proportional to the fourth power of the temperature? Does this result come from Planck's radiation law? If yes, how?

Ok, well SR is validated by experiments.. And it is proved that if two events are simultaneou s in one frame then they may not be simultaneous in another frame. And this fact is not explained by Lorentz Ether, so can't we take it as an evidence against it? There must also exist other facts which...

Ok, how do u explain simultaneity of events by Lorentz Ether Theory?

Well, I myself first understood the effects of time dilation and lorentz contraction through the ether theory. But if we assume Poincare's Hypothesis to be true then the results about the simultaneity of two events in different frames do not match with the result arrived from ether. So, if the...

Guys, I have started reading Special Relativity and used the Feynman Lectures as my starting point. As I noted, he started well with the concept of ether and told about Michelson-Morley experiment. There, to explain the results of experiment, he told Lorentz Contraction and supposed it to be...