Monthly Archives: February 2007

Your search requests answered

Today’s amusing search request: should I make an outline slide for my APS march meeting talk?
My physics category archive is the second hit for this search in Google. This is a surprising query to see from (presumably) a physicist: an overspecific question phrased in standard English is not the most well-formed Google search. (Some search engines are designed to take queries in this form, but Google is not one of them.) Nevertheless, the searcher lucked out: the fifth hit is a set of slides on giving good scientific talks.
I’ll answer the question anyway in case anyone else is wondering. If it’s an invited talk, the answer is almost certainly yes—a 30-minute talk will cover enough different points that an outline at the beginning will help the audience follow the transitions. If it’s a contributed talk, with only ten minutes of material it may not be necessary. If the talk divides nicely into multiple distinct sections, it’s a good idea, but if it’s centered on a single result you probably don’t need it.

Quantum mechanical Tomb Raider

Terence Tao explains quantum mechanics by analogizing to video games (particularly Tomb Raider):

Now, how does the situation look from Lara’s point of view? At the save point, Lara’s reality diverges into a superposition of two non-interacting paths, one in which she dies in the boulder puzzle, and one in which she lives. (Yes, just like that cat.) Her future becomes indeterministic. If she had consulted with an infinitely prescient oracle before reaching the save point as to whether she would survive the boulder puzzle, the only truthful answer this oracle could give is “50% yes, and 50% no”.
This simple example shows that the internal game universe can become indeterministic, even though the external one might be utterly deterministic. However, this example does not fully capture the weirdness of quantum mechanics…

He goes on to make some macabre modifications to the game mechanics in order to improve the analogy, bringing in interference and entanglement. It’s an entertaining post, but it gets truly ridiculous in the comments where he devises a Tomb Raider level to test Bell’s Inequality.

Cults and hierarchies in physics

There’s a great post at Cosmic Variance about the cult of genius in physics:

During high school or college, many aspiring physicists latch onto Feynman or Einstein or Hawking as representing all they hope to become. The problem is, the vast majority of us are just not that smart. Oh sure, we’re plenty clever, and are whizzes at figuring out the tip when the check comes due, but we’re not Feynman-Einstein-Hawking smart. We go through a phase where we hope that we are, and then reality sets in, and we either (1) deal, (2) spend the rest of our career trying to hide the fact that we’re not, or (3) drop out. It’s always bugged the crap out of me that physicists’ worship of genius conveys the simultaneous message that if you’re not F-E-H smart, then what good are you?

I remember clearly the moment I found that physics was much harder than I realized (although I had no delusions of being F-E-H smart by that point anyway): it was Ph 106a. I was used to being able to pick up concepts fairly quickly, but the subtleties of advanced classical mechanics (and Goldstein’s textbook) eluded me, and it was a serious blow to my confidence that I really didn’t get it. I worried that this was a sign that all the high-level physics concepts would be beyond my reach. Obviously that turned out not to be the case; I just needed to work a lot harder to understand these concepts. It’s striking to me how rapidly the difficulty seemed to ramp up, but this may have been due to the way Caltech structured the physics curriculum rather than an inherent property of the subject.
Chad Orzel has a related point:

Too many people approach physics as if there’s some sort of Great Chain of Being, with the most abstract theoretical particle physics at the very top and low-energy experimentalists down at the bottom, just above biologists and rude beasts incapable of speech.
This drives me right up the wall.
There’s no inherent moral worth to working on more “fundamental” and mathematical physics. A lack of familiarity with algebraic topology is not a defect in character, or a sign of gross stupidity. Low-energy physics is different than high-energy theory, but not inferior to it.

This is something I noticed a lot as an undergrad—in my freshman class almost everyone who wanted to do physics was interested in high-energy theory; I was rare in actually being inclined towards experiment at that point. Part of it is that there’s a certain glamour to working on the Theory of Everything, and there’s an apparent elegance to a simple but widely applicable theory that makes the experimental world look messy and ugly by comparison. (Although in fact the Standard Model isn’t really what I’d call simple or elegant.) Furthermore, at roughly the freshman undergrad level the major contact with experimental physics is through high school or freshman physics labs, which tend to be pretty lame.
(So how did I end up wanting to do experiment at that stage? At the end of my senior year in high school I had the opportunity to do some labs on more advanced topics, and they were less structured than what I was used to—instead of the procedure being laid out explicitly, I was given a set of equipment and had to figure out how to use it to measure a certain parameter or figure out how something worked. Although it was still pretty far removed from the actual practice of experimental physics, it gave me a better sense of the kind of problem-solving involved, which I found I really enjoyed. Plus I noticed I was better at it than I was at theory.)

The brilliant unintentional comedy of Conservapedia

I don’t normally go reading crackpot right-wing sites for my own amusement, but Conservapedia is one of the funniest things I’ve ever seen. In fact, I’d be certain it’s a parody if not for Andrew Schlafly’s presence as a major editor. As the name suggests, Conservapedia is supposed to be a “fair and balanced” (in the Fox News sense) alternative to Wikipedia, which apparently suffers from liberal bias. The editors of Conservapedia have helpfully (and hilariously) listed their grievances against Wikipedia, which include such major offenses as:

1. Wikipedia allows the use of B.C.E. instead of B.C. and C.E. instead of A.D. The dates are based on the birth of Jesus, so why pretend otherwise? Conservapedia is Christian-friendly and exposes the CE deception.

and

5. Wikipedia often uses foreign spelling of words, even though most English speaking users are American. Look up “Most Favored Nation” on Wikipedia and it automatically converts the spelling to the British spelling “Most Favoured Nation”, even there there are far more American than British users. Look up “Division of labor” on Wikipedia and it automatically converts to the British spelling “Division of labour,” then insists on the British spelling for “specialization” also.[3]. Enter “Hapsburg” (the European ruling family) and Wikipedia automatically changes the spelling to Habsburg, even though the American spelling has always been “Hapsburg”. Within entries British spellings appear in the silliest of places, even when the topic is American. Conservapedia favors American spellings of words.

Now, this project is still fairly new so one doesn’t expect to find extended entries on many topics. Nonetheless I was disappointed to find that many entries are… well, “half-assed” doesn’t quite describe it. It’s more like 1%-assed. A lot of entries consist of a single sentence lifted from an appropriately slanted textbook (sample title: Exploring Creation With Biology). (I want to mention that I hit the “random page” button once to find that example.) And a lot of the more likely fodder for entertainment (such as the entry for evolution) has already been edited by visiting liberals in an attempt to either correct or parody, either of which makes it less funny. Nevertheless, the best examples of teh crazy occur where you don’t expect: these guys object not just to evolution but to relativity, and there are some other gems as well. (I’m linking to people who have quoted them, since the original entries have probably changed by now.) I recommend just clicking random pages until you find something good.
Although the temptation to troll the site is immense, I have to agree with those who say we liberals should leave it alone and see what develops. The intra-wingnut edit wars alone should be worth it.

Penne alla vodka for lazy evenings

This is generating some interest on Flickr so I’m cross-posting this photo and the recipe I provided in the Flickr caption.

A streamlined recipe for quick and easy preparation (about 20 minutes total). Serves 1, but easily scaled up.

Ingredients:
1/4 lb penne pasta
14 oz can diced tomatoes
1/2 tsp minced garlic
1 1/3 tbsp olive oil
1 tbsp vodka
2 tbsp heavy cream
salt, pepper, red pepper flakes
chopped parsley and basil leaves
parmesan cheese

1. Boil water for the pasta. Heat the oil in a pan on medium heat. Drain the tomatoes.

2. Add the garlic to the pan and cook for about a minute. Add the vodka and allow about half to boil off, then add the tomatoes. Add salt, pepper, and red pepper flakes to taste.

3. Start boiling the pasta. Allow the sauce to simmer while the pasta is cooking.

4. When the pasta is al dente, drain and add to pan. Add the cream and stir over high heat for about two minutes. Add the parsley and basil, and toss. Serve with grated parmesan.

Music news for JSpur

The rest of you may also be interested:
Ted Leo’s new CD will be released March 20. (Via Atrios, who is not normally a source for music news, but Ted Leo is appropriate.) There’s also a freely downloadable mp3 at the link.
Iron & Wine are planning a release in the fall (via Pitchfork).
If you don’t know these bands, you need to listen to more of my mix CDs. Speaking of which, I should mail out copies of the 2006 CD to those who didn’t get one…

Missed opportunities

Via Dave Bacon, venture capital firm OVP has an amusing list of deals missed. For instance:

A guy walks into your office in the late 1980’s and says he wants to open a chain of retail shops selling a commodity product you can get anywhere for 25 cents, but he will charge 2 dollars. Of course, you listen politely, and then fall off your chair laughing when he leaves. Howard Shultz didn’t see this as humorous. And we didn’t make 500 times our money.

“Not investing in Starbucks in 1986″ should go into the regret index

Project 365 comments thread



captured rainwater, originally uploaded by arcanegazebo.

This is the thread for comments on my photos if you don’t want to log into Flickr to do so. I’ll put a static link to it on the sidebar.

Above: yesterday’s photo, taken after a rainstorm that happened to coincide with my walk home.