| Date | Topic |
| May 1 | We finished the fine structure correction for the hydrogen atom. We looked at the Zeeman effect (weak, strong and intermediate field). This included
working part of problem 6.23. |
| April 26 | We completed the example in the text on degenerate perturbation theory and worked problem 6.9. We began to determine the relativistic correction to the energies for the hydrogen
atom. |
| April 24 | We determined the first order correction to the wavefunction and the second order correction to the energy. We examined degenerate perturbation theory. Some hints
for the homework problems will be here shortly. |
| April 19 | We discussed the second exam. We began talking about nondegenerate perturbation theory and determined the first order correction to the energy.
We worked problems 6.1 and 6.2. |
| April 17 | We looked at the physical significance of the constants a and b that appear in the distribution functions for
distinguishable particles and for particles that obey Bose-Einstein and Fermi-Dirac statistics. We worked as examples problems 5.25 & 5.26. We applied the Bose-Einstein distribution function to a system of
non-interacting bosons (photons in a cavity) and worked problem 5.27 which is a derivation of Wien's Law and as promised, here is problem 5.28. |
| April 12 | Test Day |
| April 10 | We completed our look at the "Dirac comb model for the potential and looked at potential values for the energies and the bands and gaps that result from this model.
We began to look at quantum statistical mechanics. Six particles with total energy 8E |
| April 5 | We looked at the free electron model for electrons in a solid and found the "degeneracy pressure". We worked problem 5.31 and briefly discussed 5.32 (solution
available in HW). We looked at a more realistic potential, the Dirac comb. |
| April 3 | We showed that the expectation value of the separation between particles is different for bosons, fermion, and distinguishable particles.
We looked at the Hamiltonian for more complex atoms and solved it for helium given
the very significant assumption that the electrons do not interact. We worked problem 5.10 (part 1) & (part 2) and which gave us a correction to the estimate of the ground state energy
we had made. |
| Mar 29 | We began to look at a system of two identical particles and examined the difference between fermions and bosons. We discussed symmetric and anti-symmetric wave functions
and the parity operator.
We worked problems 5.2 a&b, 5.3 and 5.4a.. The rest of 5.2 and 5.4 are in the HW solutions. |
| Mar 27 | We discussed some of the pending homework problems. We worked problem 4.35 which looked at the singlet and triplet states for two spin 1/2 particles. We then determined
the coefficients for constructing a state with j = 1, m = 1 from two states with j1 = 2 and j2 = 1 and looked at how to get those same coefficients from the tables, problem 4.37. |
| Mar 22 | We determined the expectation values for the various components of the spin angular momentum. We looked at representing the spin state as a linear combination of the
eigenfunctions of either Sz or Sx. We looked at an electron in a magnetic field and determined the frequency of the
Larmor precession and explained the results of the Stern-Gerlach experiment. Table of Clebsch-Gordan coefficients |
| Mar 20 | We found the eigenfunctions for L2 and Lz, which turned out to be the spherical
harmonics. No surprise there. We worked problem 4.19. We looked at how the inner product notation and the orthogonality of the wave functions simplifies the calculations <Y |Li|Y>.
We then introduced the idea of intrinsic angular momentum or spin. Using the matrix notation,
we found the eigenfunctions for S2 and Sz, and the matrix representation for those operators along with
Sx and Sy.
|
| Mar 15 | We determined the first excited states for the hydrogen atom. Next, we looked at the form for the angular momentum operator
and derived the commutation relations for those operators. We derived the form of the raising and lowering operators. We recognized that there must be an upper state that if we try and raise that
state we obtain zero and a lower state that returns zero if the lowering operator acts on it. This gave us mT = -mB = l (that is "el" not one) and that l=
(l+1)l. We found the x, y, z components of the angular momentum operator in terms of spherical coordinates.
|
| Mar 13 | We discussed the solutions to exam 1. We worked problem 4.9 which is the finite spherical well for l = 0.
We solved the Schrodinger equation for the hydrogen atom, or at least have a solution to the differential equation.
We saw that the solution we have now is not a good solution from a physical standpoint. We saw that the solution to the problem that our solution goes to infinity was to truncate the power series. This truncation leads to
energy quantization and leads to the results Bohr obtained for the hydrogen atom.
|
| Mar 1 | Recognizing that many of the potentials we will encounter have spherical symmetry, we recast the Schrodinger equation into spherical coordinates and looked at the solutions to the angular portion of the wave function. We looked
at the problem of the infinite spherical well. |
| Feb 27 | We rephrased the fundamental ideas of quantum mechanics in terms of the ideas developed in the linear algebra section.
We discussed the properties of operators associated with observable quantities. We derived the uncertainty principle based on the commutator
of two operators and rederived the uncertainty principle for position and momentum. We began quantum mechanics in three dimensions and worked
the problem of the bound states for a 3-d infinite well in the shape of a cube. |
| Feb 22 | Test Day |
| Feb 17 | We introduced the idea of a function space, defined the inner product for such a space and worked problem 3.26.
|
| Feb 15 | We finished working problem 3.9. We reviewed how the elements of a matrix depend on the choice of basis and worked problem 3.14. Next, we showed how to determine the eigenvectors and
eigenvalues for a tranformation. |
| Feb 13 | We worked problems 3.4 (using the Gram-Schmidt procedure to generate an orthonormal basis from one that is not orthonormal) and 3.5 (proof of the Schwartz inequality). We looked
at linear transformations as matrices and defined several properties of matrices. We looked at how the elements of a matrix depend on the choice of basis. |
| Feb 09 | We looked at the scattering states for the finite square well and determined the transmission coefficient by applying the boundary conditions. I'll try to post that derivation. We began a review of linear algebra to help us develop a formalism for quantum mechanics. |
| Feb 07 | We worked problem 2.26., which was a double delta-function potential. We examined the bound states of the square well and determined the number of bound states and the energies of those states for a variety of potential strength parameters. |
| Feb 01 | We demonstrated that for a free particle the group velocity rather than the phase velocity agrees with our classical prediction for the velocity. We defined the dirac delta function and found the bound states and the scattering states for a delta function potential well and the scattering states for a delta function barrier. |
| Jan 29 | We continued our discussion of the harmonic oscillator by showing that the only way to have physically acceptable solutions is to truncate our power series solution. This condition
leads to quantization of energy and the energies En = (n+1/2)(h/(2p))w. We worked problem 11 from Chapter 2 which gives useful information for HW prob 12 and worked
problem 16 which asked us to determine the coefficients for the fifth and sixth order Hermite polynomials. Next we discussed methods of dealing with the "problems" we encounter with the traditional free
particle wave function. |
| Jan 25 | We discussed the simple harmonic oscillator and found solutions to the Schrodinger equation with that potential using the method of raising and lowering operators.
Next, we began to solve the Schrodinger equation for the harmonic oscillator using the analytic method. Extra Information Prob 2.11
Prob 2.13 |
| Jan 23 | We worked through the remainder of problem 6 from Chapter 2, verified the theorems in problem 1 of Chapter 2 and worked problem 9 from Chapter 2, which asked us to determine the expansion cofficients for the function defined in problem 8. |
| Jan 18 | We verified in extreme detail the fact that once the wave function is normalized, it remains normalized. We also determined the time derivative of the
expectation value of the position and used that to define the momentum operator. We also introduced (briefly) the uncertainty
principle. Next we found the time independent Schrodinger equation and discussed the properties of the solutions to this equation. We found the solutions to the Schrodinger equation for a particle in an infinite well. |
| Jan 16 | We reviewed line spectra and the Bohr atom. We discussed the wave nature of particles and gave an argument (though not rigourous proof) for the Schrodinger Equation. We discussed probability and worked problems 1 & 3 from Chapter 1. We discussed the normalization condition and showed that it is time independent. |
| Jan 11 | Introduction |