Recent content by PBTR3

  1. P

    X^4 perturbative energy eigenvalues for harmonic oscillator

    Yes! I am very much a novice at this and when books give an answer it usually helps greatly BUT when the answer published is wrong it causes much difficulty. Yes that is my typo. I am not perfect either. Also I throw out the odd powers because the integral they represent is zero from...
  2. P

    X^4 perturbative energy eigenvalues for harmonic oscillator

    I am still trying to figure out how to fix that relevant equation post.
  3. P

    X^4 perturbative energy eigenvalues for harmonic oscillator

    (a + a*)^4= a^4+a^3a*+a^2a*a+a^2a*2+aa*a^2+aa*aa*+aa*^2a+aa*^3+a*a^3+a*a^2a*+ a*aa*a+a*aa^2+a*^2a^2+a*^2a^2+a*^2aa*+a*^3a+a*^4 then throw out all terms with unequal powers of a and a* which are 0. ##\langle n | a^2a*^2 | m \rangle=\langle n | (m+1) (m+2) | m \rangle## Results for the rest are...
  4. P

    X^4 perturbative energy eigenvalues for harmonic oscillator

    The book(Schaum) says the above is the solution but after two hours of tedious checking and rechecking I get 2n^2 in place or the 3n^2. Am I missing something or is this just a typo?
  5. P

    A Calculating Functional Derivatives: -1≤xₒ≤1 vs -1<xₒ<1

    I could not get the Latex Preview to work until now. This is more like what I intended.
  6. P

    A Calculating Functional Derivatives: -1≤xₒ≤1 vs -1<xₒ<1

    ##\frac {\delta I[f]} {\delta f(x_o)} = \int_a ^b \delta(x-x_o) \, dx## with a=-1 and b=+1 ## -1 \leq x_o \leq +1 ## vs ## -1 \lt x_o \lt +1 ##, 0 otherwise. Which is correct and does it matter when doing integration by parts?
  7. P

    A Relativistic derivation of E=1/2MV^2 from QFT or Diriac or other

    I Great. Now I will spend some time (maybe weeks)going through your math (at 4AM?) in detail. This also implies that if m approaches zero and light is c that E=pc for a free, massless, relativistic particle, which is what I am trying to prove.
  8. P

    A Relativistic derivation of E=1/2MV^2 from QFT or Diriac or other

    Thanks. The photon should have an energy operator(Hamiltonian?) I need to learn how to use LaTex. It does not seem to work with Android or Linux. When I get that worked out I will resume this thread.
  9. P

    A Relativistic derivation of E=1/2MV^2 from QFT or Diriac or other

    I agee but I should be able to show E=pc for a photon. I can use Lagrange's diff equation to recover F=ma for a nonrelativistic free particle. I can use Schoedinger's diff equation to recover E=1/2mv^2 for a nonrelativistic free particle. There should be a diff equation that recovers E=pc...
  10. P

    A Relativistic derivation of E=1/2MV^2 from QFT or Diriac or other

    It is easy to derive E=1/2mv^2 from the Schroedinger equation for the nonrelativistic one dimensional case where e^ipx-iEt/\hbar is the free traveling wave function: i\hbar x -iE/\hbar x e^ipx-iEt/\hbar = - - \hbar^2/2m x p^2/2m x e^ipx-iEt/\hbar which reduces to E=1/2mv^2 Where should I start...
  11. P

    Symmetry of gravitational field to electric field and Maxwell equation

    Symmetry is an important way to find new physical laws according to Feynman. The equation that describes the electric field and the gravitational field are quite similar. Since the electric and magnetic fields are well defined by the Maxwell equations could it be possible, by symmetry, that...
  12. P

    Energy of photons vs classical physics energy

    Energy of photon vs classical physics energy Thanks for the replys. I was trying to understand what happens to energy of a proton as a proton is accelerated from rest to almost the speed of light as in the LHA. I think I can calculate that now. hjr
Back
Top