Recent content by shehry1

  1. S

    Srednicki 34.15 - Notation Question

    Homework Statement Is the index notation in Srednicki's 34.16 correct given what he does in 35.29. Essentially, in going from 34.15 to 34.16, when taking the hermitian conjugate, he does not remove the dots. In going from 35.27 to 35.29, he has done so (the dot on 'a' has moved over onto...
  2. S

    Weinberg Vol 1: (2.4.8)

    Thanks a lot. Now I have just two short questions: (1) In the last expression with the string of equalities, could you have expanded the bracket differently. Meaning that instead of \eta_{\mu\rho}\Lambda^\rho{}_\sigma\omega^\sigma{ }_\lambda(\Lambda^{-1})^\lambda{}_\nu , would it had been...
  3. S

    Weinberg Vol 1: (2.4.8)

    Can anyone explain to me why in going from (2.4.7) to (2.4.8) the indices on the LT are arranged in the way they are. Why is mu the first index (lower) and rho the second (upper)? Could they have been arranged in any other way? From the rules that I know, they can.
  4. S

    Conducting planes in magnetostatics

    Well. To put it in another way. How would the boundary conditions change in case the sheets were made out of dielectrics. As far as I understand, there cannot be any difference. Thanks a lot for answering. I had given up on it.
  5. S

    Conducting planes in magnetostatics

    Homework Statement Two infinitely long perfectly conducting planes at x = 0 and y = 0 form a boundary on the upper right quadrant (x > 0, y > 0). A magnetic dipole m = m_x + m_y [with their corresponding unit vectors] is located at at (x', y', z' = 0) in the upper right quadrant. Find the...
  6. S

    Dipole interaction potential for mixed species

    Homework Statement Not a homework question. I need the solution to this to model another problem. We all know the potential for the electromagnetic dipole dipole interaction (e.g. see Jackson) I want to know if there is a solution to the problem in which there are several replicas of the two...
  7. S

    Simple pendulum phase space

    Homework Statement Pathria 2.6 (2nd Edition): Phase space volume of a simple pendulum. The total energy can be expressed in the form of the time derivative of the angle + the Sin^2 of that angle. From this I want to calculate the phase space volume. Mathematica gives the solution in the...
  8. S

    Jackson 6.5c

    Homework Statement I need some guidance concerning Jackson 6.5c. Specifically I cannot get the -1/3 factor that the statement says I should. Homework Equations Solutions to part a and b which are given in the problem statement. The Attempt at a Solution -I started from the volume...
  9. S

    Retarded potential

    For a while you had me worried :) I can change the limits later of course but I wanted to know how to solve that wretched integral. But I do think that the problem allows me to consider a point in a single plane. In any event, it seems that I am on the right track and only need to solve...
  10. S

    Retarded potential

    Pretty sure that you have to and for two reasons: [1] Wiki says that its for time varying currents and charges without ever mentioning finiteness [2] Just saw that Griffiths example 10.2 solves for an infinite line current as well. However, the time dependence over there is not sinusoidal
  11. S

    Retarded potential

    Homework Statement The question concerns a square loop in the presence of an infinitely long sinusoidally varying line current. The complete problem is" [Broken] Homework Equations The retarded potential. The Attempt at a...
  12. S

    Jackson 6.4 (Multipole Expansion) (induced surface charge) + (induced volume charge) = 0. Thanks a lot.
  13. S

    Jackson 6.4 (Multipole Expansion)

    I was (implicitly) under the impression that the rho calculated would be valid for the surface as well. Could you kindly give me a physical reason for its not being valid at the surface. Regards
  14. S

    Jackson 6.4 (Multipole Expansion)

    Homework Statement Jackson 6.4b Homework Equations Multipole expansion especially Eq 4.9 in Jackson which is for a Quadrupole The Attempt at a Solution I found the result in 6.4a. The rho over there tells us that there is a charge density inside the sphere. Since the charge density...
  15. S

    Ideal gas law and temperature

    Homework Statement This is Pathria (2nd Ed) 1.6 and it seemed simple enough but the magnitude of the answer seems unbelievably large: A cylindrical vessel 1 m long and .1 m in diameter is filled with a monoatomic gas at P = 1 atm and T = 300 K. The gas is heated by an electrical discharge...