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Passing
Notes
Wordplay and puns were high humor at Oberlin College. I tried to join in. One day before class I made a comment about a "daymare." Halfway through the lecture, someone handed me a note. It was Jan Olson.
In Jan's case, she majored in physics because that was the closest that Oberlin could offer to a major in pre-med. She went on to medical school and became a doctor. We still correspond, even today. And we corresponded then, too, even sometimes during class. I suppose that today's college students use their cell phones and pagers to send "instant messages" to each other. Back then, we used pen and ink. Therefore, our notes were slightly more erudite. And I still have, mixed in with my now-incomprehensible notebooks from physics lectures, some of those messages.
On an upper floor of the Wright Building near our classrooms and labs, there was a small quiet room with reference books, the Physics Library. One day a student in the Library looked up and saw a silent tableau. Jan and I entered and found a dictionary. She looked up a word and triumphantly showed it to me. I peered at it and nodded reluctantly. I fished a penny out of my pocket and gave it to Jan, and we turned to leave. The student burst out laughing.
For example, in April 1968 we aimed a laser (a recent invention) through a 0.66-millimeter pinhole, projecting this diffraction pattern onto a sheet of photographic paper 26 feet away. After a half-hour exposure, we developed the "photograph" and measured the rings (spaced about 8 mm apart) to determine the wavelength of the light. Our result, 6595 Ä, was 4.2% longer than the value on the laser's label.
The following month, we attempted to re-create Robert Millikan's 1910 experiment that determined the value of e, the charge of an electron.
Some spheres travel at different speeds because they have a slight electric charge, corresponding to a few extra electrons. The electric field interacts with these spheres and causes them to move faster or slower, depending on how many extra electrons they've got. Because electric charge is quantized, our results should cluster around certain values, corresponding to spheres with two extra electrons (2e) or three (3e) or four (4e) and so on. And that is what we found, at least as far as 5e. On this graph, our results are sorted from slowest to fastest. They cluster around the vertical lines. The numerical distance between the vertical lines allows us to estimate the charge on an electron as 1.74 x 10-19 coulomb, which is within 9% of the accepted value.
Beyond 5e, the spheres were moving too fast for us to time them accurately. This meant that the data became too noisy to use. Notice how there are no longer clusters. Nine years later, however, Stanford's William Fairbank used a much more refined version of this experiment to apparently detect free quarks. These are subatomic particles which have either 1/3 or 2/3 of the charge of an electron. I wrote Jan to argue that perhaps we had detected quarks ourselves. The data points shown in red might represent 5.67e, 7.33e (twice), 7.67e, 9.33e (twice), 11.67e, and 13.67e (twice), which in turn would imply some combination of quarks and electrons. I don't think that I convinced her, though.
Finally, there was the story of the Relativitator. Physics classes covered many subjects, from a drumhead's modes of vibration to Einstein's theory of relativity. The lectures were supplemented by several pages of handouts, stapled together for our convenience. Some students removed the staples in order to store the pages in a binder, so loose staples were lying about. I picked them up. (Why? Click here.) How to recycle used staples? I linked them into a chain, and from the chain I hung a Flexible Membrane Relativitator. This was a thin rubber belt (cut from the neck of a balloon) stretched over a bent paper clip. The Relativitator appeared to be either a pendant or a tiny kazoo. Actually, of course, it was a highly sensitive device for examining questions on the cutting edge of science. I entrusted this instrument to my fellow investigator. But she arrived slightly late for a subsequent class and passed me a Runic note, which I translate here.
From the length of this exchange, written in another alphabet no less, you can tell that the instructor had our full attention.
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