Recent content by metalrose

Hi, I have been looking for rigorous mathematical conditions for when the WKB approximation may be applied. Here is my understanding of the topic. We start with the most general form that the wavefunction could take, i.e. exp[if(x)/h] , Where "i" stands for square root of -1, f(x) is...

I'm an electronics and communication engineering major from India and will be applying this fall for graduate school in 2014 fall. I was really interested in theoretical physics uptil now (cosmology, strings, hep etc.) and still am but given the abysmal employability of these areas of study, i...

I missed out on a subtle point in my book. Hence the confusion. I think i am clear now. Thanks for the replies anyway.

What you seem to have done is this : Ʃiaii However, my question is regarding Ʃij(aij)*(aij)

The summation convention for Tensor Notation says, that we can omit the summation signs and simply understand a summation over any index that appears twice. So consider a 3X3 matrix A whose elements are denoted by aij, where i and j are indices running from 1 to 3. Now consider the...

That clears it up. Thanks a ton.

I get that. That's what i thought you meant. How can you say this? All that isotropy of space implies is that the bullet fired from G' will move with speed v relative to the gun G', irrespective of wether the gun G' points in the positive x' or negative x' direction. I don't understand...

Could you expand a bit more on what you mean by isotropy of space and how the above statement should therefore be true?

Also, my textbook, just after defining inertial frames in the above way, immediately says, I think this is equivalent o the definition you gave.

Also, I quoted my definition of the first postulate and inertial frames from the modern physics textbook by john r. Taylor. I quote again, Inertial frame: an inertial frame is any reference frame ( that is, system of coordinates x,y,z,t), where all the laws of physics hold in their...

None of the above made any sense to me, that's because I am still a junior in undergrad. Any resources i could use at this point to understand the above ??

Accelerating with respect to what ? Rest or constant velocity with respect to what ? The definition i used is a textbook definition. An inertial frame is one where all laws of physics are valid. Now, if some other frame i moving with respect to this inertial frame at constant velocity...

That makes sense i guess. Thanks a lot.

Lets attach frame S to the object A and frame S' to the object B. Now your argument definitely makes sense because there's a spring that's doing the same thing to both A and B, and so, unless there's some weird stuff going on related to initial positions and stuff, by symmetry, the relative...

Ok, i get that. To say that the principle of relativity doesn't hold is the same as saying that the laws of physics are different in the two frames. That would lead to the gun behaving differently in the two frames. Which means the two observers will measure different muzzle velocities. But...