Category: Teaching

Quotes which I put on the final for my quantum computing class:

“I didnt’ fail the test, I just found 100 ways to do it wrong.” — Benjamin Franklin
“People will accept your idea much more readily if you tell them Benjamin Franklin said it first.”–David H. Commins

Unfortunately I didn’t put a comic on the test. It always seemed that the exams I took in intro level physics and chemistry courses at Caltech, or the ones I saw in similar courses at Berkeley, always had either a Far Side or a Calvin and Hobbes comic on them. In fact, I have a conjecture about this. I’m convinced that you can identify the exam by the comic on the front of the exam. Far Side: physics. Calvin and Hobbes: chemistry. But this just may be a result of my local experience.

Well, my grades are all turned in, and so I’ve pretty much officially finished teaching my first class. On the final, I had an extra credit problem which was basically the GHZ problem. It was very interesting to see the different ways in which the students would come up with a contradiction for the impossibility of winning the GHZ game. My favorite was the student who wrote a spreadsheet for every single possible strategy and showed that none of those would win. This is such a computer science way to solve the problem: I love it! The students all did remarkably well on the final and I was very happy with their final scores (they may be more or less happy.) One of the students didn’t miss a point the entire term!
This week I’m preparing my lectures for a summer school in Italy. Again it will be a course for graduate students in computer science. Pretty soon Dirac notation will be standard in computer science departments 😉 Here is my favorite quote about Dirac notation:

Mathematicians tend to despise Dirac notation, because it can prevent them from making important distinctions, but physicists love it, because they are always forgetting such distinctions exist and the notation liberates them from having to remember.–David Mermin

Well, I just finished my last lecture for the quantum computing class I taught this summer. Now all I have to do is grade the final and submit grades. The class started roughly, with me going too fast, then things smoothed out, and then a tough homework hit, and then things sped up again. Not what I was shooting for, but, well, live and learn. I would say that I am 60 percent happy with the way the class went: i.e. I’d give myself a D.
What would I do different? Lots of things. One is that I might try to teach the course along with one of the quantum simulator programs. These are, after all, professional masters students in a computer science program. This means that the majority are programmers. And programmers, well they like to learn by programming. So I think I would teach it that way for this particular audience.
I have to teach a quantum course in Italy to graduate students in computer science coming up in a few weeks. The course will have twelve hours of lectures and a two hour final examination. How do you talk about quantum computation in twelve hours? Four hours to introduce quantum theory, four hours to build up to quantum algorithms, two hours for quantum error correction, and two hours for quantum cryptography? Or is it better to do more surveying of results? It’s an interesting question and one I’ll be struggling with for the next week.

A confession. When I was an undergraduate, I really didn’t go to classes as much as I should have. In particular, I didn’t go to many of my physics and math classes. Why? Mostly because these were the classes where I had the least problem picking up the material and my own self-motivation to learn the material on my own was almost always enough to carry me through the class. So the classes I attended the most were my humanities classes (to get that valuable B.S. in literature 😉 ) and my elective scientific courses, particularly the courses I took in computational neural science. Now that I’ve started teaching my own class, I wonder how much my own teaching suffers because of my past habits skipping class?
One thing I’ve noticed is that I have a hard time lecturing around a textbook. I have this insane desire to explain the subject material in my own words, and following a textbook closely makes me feel like I am not much more than a glorified parrot. I think, perhaps, this just has to do with my own proximity to the subject matter I’m teaching, quantum computing. Teaching about a subject which is not your own field of research in some ways seems like it would be easier, because you feel less of a desire to make sure you get it just right.
I am also fighting, in my own teaching, the three subject structure which was prevalent at Caltech. The three subject structure was the expectation that a course would involve lectures on one part of the subject, homeworks on another, and tests on a third part. Of course there was always some overlap, but there was also a lot of “thrown them into the fire” homeworks and tests. I can’t count the number of times I realized halfway through a test, “Oh, so this is what that means!” Fine for self-motivated self-learners, but not the best for everyone else.
Anyway, I think I’m slowly beginning to learn to teach. The first lecture for the course, I, uh, how to put this nicely, well I totally misjudge the appropriate difficulty level I should have been shooting for in the classs. In particular, I’m teaching the course to professional master’s students in computer science, some of whom have been out of school for a few years, and so, while I may want to teach them quantum theory in one lecture, this just is not very realistic! So starting in lecture two, we slowed down the pace quite a bit. Now entering into the fifth lecture, we’re beginning to get to things which I would consider truely quantum computing subjects. Now the challenge will be, again, to restrain myself from running rampshot through this material. Certainly there last homework was significantly harder than their first two, so I’m really trying to slow the pace as we enter the really cools stuff in quantum computing. Interestingly, slowing down has resulted in, I think, teaching the material in a careful manner, but has also kept me from teaching the big picture as effectively as possible. Mixing these two styles, big picture and instruction on the details, is something I’m working on.
Well, back to working on my lecture and the next homework set!