You never know where you are
going to find the three red volumes of the Feynman Lectures on Physics1.
Just a few days ago (it is now 23 April 2024) I found them on page 93 of a
review copy of “Her Space, Her Time” by Shohini Ghose (2023 MIT Press), where
the author describes the occasion when she and her fiancé both completed their
PhDs and married. Their thesis advisor asked what gift they would like to mark
the event. She requested “a beautiful bound copy of Feynman’s Lectures in
Physics for my fiancé, not knowing that he had done the same for me.” She does
not record whether they currently have two, one, or zero copies, but in any
case, replacements are available, in the form of hard copies for $100-$200 from
various booksellers and even free online. The actual recorded lectures are also
“there,” and I recommend a bit of a listen if you never heard his voice in
life, or maybe even if you did. The pitch sounds a bit lower than I remember,
but the accent and the quirkiness and all are there.
I arrived at Caltech for the fall semester in 1964 (when women graduate students
were admitted “only under exceptional circumstances” and undergrads not at
all), just a year too late to have heard the second year of the initial, live
lectures, frequently said to have attracted more and more grad students,
postdocs, and faculty as the series went on, though of course they were meant
as the first two years of basic physics for the undergraduate majors. It
has also been said that Caltech basically lost a year or two of physics majors
to the experiment of having Richard Feynman as the instructor of record and
reality for the course. It has also been said that every student got something,
though very few got everything, out of the course. Perhaps both are true. And
well into the 1970s and 1980s many of us Caltech lecturees who had become
lecturers recommended the volumes to graduate students who were studying for
various sorts of qualifying exam.
Have I used the volumes lately for anything myself? Truthfully not,
though I dug recently into a preliminary version of what became his text on
gravitation to see what he had said about the reality, or perhaps the
energy-carrying capacity of gravitational waves or radiation. Actually the treatment
in those notes focusses on gravitons, though he is generally credited with (one
of the) definitive proofs that the waves exist and can carry energy away from
bound systems. The example generally shown, however, is one where there are
also non-gravitational forces holding things together, and the most bitter
disputes were always over cases with only gravitational forces involved. Quoting
Einstein just here is not relevant, for what he wrote to Karl Schwarzschild in
1916 was that there would be no waves analogous to electromagnetic waves, that
is no dipole waves, which is perfectly true.
Fig. 1 From left to right, Gweneth Feynman, Richard Feynman, his sister Joan Feynman, and Virginia Trimble in the Caltech fall party that happened a few days after the Feynman’s Nobel prize (1965) was announced.
What was it like to listen to a Feynman lectures? I have a number of
specific memories stored. First, just after his 1965 Nobel Prize was announced,
we grad students (astronomy, where I was, as well as physics) asked for a talk
just for us. He generously obliged and spoke on “the absorber theory of
radiation,” something he had worked on as a graduate student with John Archibald
Wheeler. The idea is that the wave equations of Maxwellinan E&M are time
symmetric, yet we always see radiation going forward in time. What happens
to the advanced potentials? Well, suppose there is a perfect absorber somewhere
far out there in the distance, sending its advanced potentials back at us. They
cancel, and so we observe only the retarded potentials. Also long ago, some
supporters of Steady State cosmology claimed that only their universe had a perfect
future absorber. Perhaps it is so.
Fig. 2 James Gunn and Virginia Trimble in 1972 at an early meeting of the AAS High Energy Astrophysics Division (HEAD), Pasadena, a meeting also attended by Richard Feynman (courtesy of Trey Wenger).
Second, he gave two lectures here at University of California, Irvine at
my invitation. The first was at a memorial symposium held in 1978 honoring the
late John R. Pellam (a UCI founding faculty member who had come to us from
Caltech, and who died of ALS in July 1977). I was the newest faculty
member, and the department chair (Richard Wallis) and physical sciences dean
(Fred Reines) instructed me to put together both a scientific program and meal
arrangements and not spend more than $XYZ (all amounts from the 1970s sound
ridiculously small today). I reconciled myself to calling in some chips and
asked Richard Feynman if he would speak. “You mean you want me to give the
principle eulogy?” he asked rather gruffly? “No, no,” says I, “we
want you to talk about whatever you currently think is interesting in physics
these days.” Well, he came and, as was nearly always the case with Feynman
lectures, we all walked out feeling greatly inspired but not actually able to
do any calculations that we hadn’t been able to do before. Incidentally,
I always called him Richard as did his third wife Gweneth and my husband.
Fig. 3 A photograph taken during the Pellam memorial event mentioned in the text (1978). Virginia Trimble is on her back and Richard Feynman is hollering at her.
The second of Richard’s UCI lectures at my invitation was in spring 1987,
the year before he died, when I had been put in charge of the departmental
colloquium series. Willy Fowler came and was a wonderful guest! He
let me pick him up from Pasadena, enjoyed his Orange County lunch, gave a great
talk (having just won his Nobel Prize), laughed heartily when a female
undergraduate brought him a dry martini as he was turning off his last slide. Feynman
was not a wonderful guest. He refused a ride and lunch invitation; insisted on
being driven by one of his then-current Caltech students, refused driving
suggestions, and believed a UCI particle theorist about the likely time
required for the southbound leg of the trip. It was and is about 55 miles - 45
minutes with incredible luck or creative description, but it used to take
me more like 60, and I always allowed 90. So he arrived late, frazzled, angry,
cursing a misleading map that made it look like you could do a particular turn
rather than looping around, cursed the orange control bar on the overhead
projector (“what orange bar? Like that damned map”). Refused food or drink after
the talk, refused the honorarium (saying to donate it to some local charity -
not an easy thing to arrange); and so forth. And everybody else was angry with
me as well, because the UCI office staff had insisted on putting him name on
the colloquium announcement rather than the requested pseudonym2 “Dick O’Fey.” Thus the auditorium filled with folks from all over campus
well before the start time, and neither most of the UCI faculty nor our own
grad students, who were his target audience could get in. We more or less made
friends again afterwards, but…
Finally, at least here, were some Caltech lectures he gave primarily for
undergraduates once again, under the rubric “Ask me anything.” I had the
privilege of being his “back up astronomer” for a few of these. You will
surely have heard (I think rightly) that Richard always wanted to think
through, work through, calculate things on his own, by his own methods, rather
than trying to follow someone else’s. But he did not disdain actual facts from
observations or experiments. Indeed, many of the things he achieved in physics
over his too-short lifetime came from paying very close attention to the details
of such facts and the numbers after the decimal place, and his ability both to
inspire and to see things differently, and probably more clearly, than most of
his colleagues lasted to the end.
Oh, might you wonder why I could possibly have any chips to cash in at
such a high-end casino? If you have read “Surely you’re joking, Mr. Feynman”
you might remember the female graduate student who posed naked for him when he
was learning to draw (in 1965-66). I was the graduate student, and Gweneth used
to bring us orange juice and cookies for a mid-evening break.
Fig. 4 Richard Feynman's stunning portrait of astronomer Virginia Trimble, 1965. It is just signed DICK ’65 and titled ‘Astronomer’.
The next girl I met that
I wanted to pose for me was a Caltech student. I asked her if she would pose
nude. “Certainly”, she said, and there we were! So it was easy. I guess there
was so much in my mind that I thought it was somehow wrong to ask. (Excerpt from “Surely you’re joking, Mr.
Feynman.”)
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