Physics 3220 Quantum Mechanics

Instructors: Steven Pollock, Oliver DeWolfe, and Steve Goldhaber


The development of Quantum Mechanics was very much a collaborative effort - there was no "lone hero" sitting alone in their office inventing it all, as we imagine Newton did for his laws of motion, or Einstein did for relativity. The picture above shows the participants at the 1927 Solvay Conference, who together shaped the creation and growth of the quantum theory and represented an extraordinary gathering of clever people - 17 of them had, or went on to get, Nobel Prizes. Marie Curie got two, in two disciplines! How many can you identify? This was the conference where Einstein, disenchanted with Heisenberg's "Uncertainty Principle," remarked "God does not play dice," to which Bohr replied, "Einstein, stop telling God what to do."

By way of introduction to our course, here are some more amusing quotes about Quantum Mechanics.

Week 5 (Sep 22-26):

Friday Sep 26: Solutions to Homework #5 now posted at CULearn.

Sunday Sep 21: Extra credit survey. There is a brief online participation survey available here. Please take a few minutes to fill it in - this kind of information is extremely helpful to us! Please fill it out soon, as it won't be online for very long. The survey will be worth extra credit, like clicker points. Thanks!

Week 4 (Sep 15-19):

Friday Sep 19: On HW#5, try problems 5.4 and 5.5 first. In class we have gone over the material for the last two problems on the set, but won't get to the material for the first three until Monday. Those problems are still doable, but might make more sense in context.

Friday Sep 19: Have you tried the PhET simulations? The PhETs are interactive demo programs that run on your computer, illustrating some aspect of physics. Check out the Quantum Bound States PhET. You can choose from several different potentials - give "Harmonic Oscillator" a try. You can see the energy levels, and plot the stationary state wavefunctions and probability densities. There's a button to make a combination of stationary states, and you can watch it evolve in real time. Or try the square well potential, and play with the height and width of the well and watch the energy levels change.

You can find the whole list of "Quantum Phenomena" programs here. The PhETs require Java.

Thursday Sep 18: Solutions to Homework #4 now posted at CULearn.

Thursday Sep 18: Typo in Homework #5 corrected. Equation 20 in problem 5.5 now has a factor of one half, V(x) = alpha x^4 becomes V(x) = (1/2) alpha x^4.

Wednesday Sep 17: Homework #5 now posted.

Problem 5.5 is another numerical problem. Again you are welcome to use whichever mathematical software you like, but if you want to use Mathematica, a sample code to get you started is given in the text. A short notebook already containing the same code is available here.

Week 3 (Sep 8-12):

Friday Sep 12: Midterms in regular classroom. Both midterms will be in G2B47, our regular classroom. Again, they are Thursday October 2 and Thursday November 13, both from 7:15pm-9:15pm.

Thursday Sep 11: MIDTERMS MOVED. As discussed in class, conflicts with other classes have forced us to move both midterms from Tuesday to Thursday in the same week. The exams are now THURSDAY OCTOBER 2 and THURSDAY NOVEMBER 13. They are both still 7:15pm-9:15pm, location to be determined.

Thursday Sep 11: Solutions to Homework #3 now posted at CULearn.

Wednesday Sep 10: Homework #4 now posted.

Problem 4.3 involves using some mathematical software. You are free to use whichever program you wish, but if you don't have a preference here is a Mathematica notebook that might contain some helpful commands: long version and short version.

Week 2 (Sep 1-5):

Friday Sep 5: Typo in Homework #3. The first equality in (7) should have had B e^{-ikx} instead of B^{-ikx}; fixed in new version.

Wednesday Sep 3: Tutorial now Fri 3-4pm and Fri 4-5pm. To accomodate people's schedules we have doubled the time available for tutorial. Please come at 3pm (right after class) or at 4pm on Fridays. The tutorial is stil designed to be an hour's worth of material, so you are not expected to stay for two whole hours.

Wednesday Sep 3: Homework #3 now posted.

Wednesday Sep 3: Solutions to Homework #2 now posted at CULearn.

Week 1 (Aug 25-29):

Friday Aug 29: Advertisement for Departmental Honors! In the physics department, honors is received by working with a faculty member on research and writing a thesis. Students can take the honors course for up to 3 consecutive semesters; it's 2 credits per semester. To be allowed into the program a student needs a 3.3 or better GPA. If you're interested, talk to John Cumalat in F-321 (Gamow Tower 3rd floor), or email him at jcumalat at

Wednesday Aug 27: Homework #2 now posted.

Monday Aug 25: Welcome to Physics 3220, Quantum Mechanics I.

Get to know the features of this web page! We hope it will prove useful. New homeworks and reading assignments will appear at the assignments page; feel free to check out the first homework and start reading the text (Introduction to Quantum Mechanics, 2nd Ed., by David J. Griffiths). At the schedule page you can see what we plan to talk about in class on what day, and also see the readings. We are making lecture notes available, which are intended to go beyond what is said in class, and there is a page that will contain concept test questions from class as well. There is also a virtual office hours page, where questions emailed by you are answered by the instructors.

You can also have a look at the course syllabus, information on grading and exams, information on clickers, and a summary of the information on TAs and office hours (to appear).

Special notes:

Last but not least: If you haven't done so, I encourage you to visit today to register to vote (or to update your voter information.)

We welcome your comments on the class and this website. Send them to steven.pollock at or oliver.dewolfe at