1. Daily
Update Monday Oct. 13
a. Woke
up, breakfasted on peanut butter banana, then took physics test. It went fine—I
answered all the questions and don’t think I missed any, but there were enough
questions that my first pass over the questions left me with little time to
blunder-check.
b. Did
hw with Eleanor, John.
c. Went
to Lunchbox Seminar. This time speaker was a young professor from Stanford by
way of Cambridge and some other prestigious places. He discussed the connection
of classical (Einstein, non-quantum) theories describing black holes to
descriptions of systems involving strongly coupled interactions, specifically metals
that don’t conduct normally. It was pretty intense, but here’s my “quick”
breakdown:
i. Electrons
in conducting metals actually interact strongly with each other, but because
all the momentum states available to the electrons in the metals are already filled,
(Pauli exclusion principle dictates more than two electrons can’t occupy same
state) the electrons can’t scatter into new states, so we can treat them as if
they don’t interact significantly with each other and act as “billiard balls”
influenced only by potential field.
ii. A
specific class of metals that don’t conduct normally, when electrons are
intentionally removed or added so that the electrons can move from state to
state and interact with each other, offer such high resistivity to flow that
the implication is that the mean path the electron can travel before hitting an
obstruction is less than the “wavelength” that the electron has when considered
as wave.
iii. I’m
fuzzy on this, but these strong electron-electron attractions and the other
quantum-dynamical effects having to do with wavelength > mean free path
makes the interacting electrons a strongly coupled system.
iv. Which
brings us to similarities with black holes, “strongly coupled systems”.
v. These
respond to perturbations like normal thermodynamical systems do; by diffusing
them across the entire black hole.
vi. Which
leads to strong thermodynamical/entropy-related analogy where the black hole
can be thought of as the strongly coupled equivalent of a normal
thermodynamical system.
vii. Darn
it, I guess I didn’t really understand it all that well. Bits and pieces.
Later, at 4:00, I went to the full colloquium version of the talk (my physics
professor was there, and we talked a little tiny bit about the research he was
doing.
viii.
At the colloquium, he talked about the
characteristics of the weird metals a little more, showing how the conductivity
of the metals with respect to temperature could be theoretically related to the
black hole’s responses to perturbation with respect to the “temperature” of the
black hole, (which is the energy that the “paired” particles it somehow
quantum-dynamically emits). He discussed a peak in the conductivity function
called the Drude (Drud-uh) peak, and described how quantities relating to the
peak could be computed with the black-hole approach. He finished with a
discussion of how the similarities in the metals’ conductivities could be the
results of fundamental bounds on entropy and “viscosity”. Complicated.
ix. Just
want to point out I’ve now heard from an experimenter and a theorist, and their
perspectives on physics were wildly different. I think observing that split
will be interesting.
d. Went
back to dorm, did a little hw, then went to CS class. Discussed complexity
analysis and three algorithms for finding the subsequence with the maximum
cumulative sum within an array of positive and negative integer values; the
most efficient O(n) algorithm was very clever.
e. Went
to physics colloquium, described above.
f. Intended
to go to chess club, but randomly found Go club hanging out in the Society of
Physics Students lounge. They were very nice. I played a training game, finally
learned how Go’s dang-gone scoring system works. I happened to guess correctly
what research a biochem major, Rachel, was doing, and she recommended me a
paper by a UW prof.
g. Went
back to dorm. Ate dinner (chicken strips at the 8) with Jamie. Then we headed
to Ultimate. I played pretty well and actually scored 3 goals, but our team
lost :(
h. I
decided, in a crazy LEROY (there’s a strange inside joke associated with the name
Leroy Jenkins; if you don’t know what it refers to, I associate Leroy with
hustle and reckless abandon) move, to go back to the dorm, change shoes, and go
play badminton with the Badminton Club, which I’d been neglecting for the past
2 weeks.
i. I
got my butt kicked by a guy in my CS Honors class and went back to the dorm.
Posted my discussion question for the education class, then went down to Rick’s
for cheap ice cream. I met up with Xin on the way down. (I don’t think I’ve
mentioned Xin (pronounced Sheen) yet; he’s a super nice guy in my physics
class, very guileless and always smiling. I played tennis with him and his
roommate Hayden a couple days ago.) He said, smiling, that the physics test had
ruined his day. But he was beaming like a loon when the Rick’s volunteer
scooper rewarded his $1.75 for a single scoop in a waffle cone with the most
enormous mound of ice cream I’d ever seen. He had to share it with people in
the lounge.
j. I
ate my ice cream and read physics.
k.
Wrote log and went to bed.
