Expander graphs, gonality, and variation of Galois representations

31Aug10

New paper on the arXiv with Chris Hall and Emmanuel Kowalski. Suppose you have a 1-dimensional family of polarized abelian varieties — or, just to make things concrete, an abelian variety A over Q(t) with no isotrivial factor. You might have some intuition that abelian varieties over Q don’t usually have rational p-torsion points — [...]

Filed under: math, papers   |  5 Comments
Tags: abelian varieties, algebraic geometry, esperanto, expander graphs, expanders, Galois representations, gonality, graph theory, hall, kowalski, number theory, spectral gap, torsion

Iranian election statistics — never mind the digits?

30Aug10

I blogged last year about claims that fraud in the 2009 Iranian election could be detected by studying irregularities in the distribution of terminal digits.  Eric A. Brill just e-mailed me an article of his which argues against this methodology, pointing out that the provincial vote totals (the ones with the fishy last digits) agree [...]

Filed under: math, politics   |  Leave a Comment
Tags: beber, brill, digits, election, iran, scacco

Counting Canadians

25Aug10

Canada’s chief statistician resigned last month in protest of the government’s decision to replace the long-form census questionnaire, previously mandatory for 20 percent of the population, with a voluntary version.   I imagine the point is that a voluntary questionnaire can’t possibly be delivering anything like a random sample of the population, though the linked article [...]

Filed under: bad statistics, politics   |  8 Comments
Tags: canada, census, sampling

In which I make oblique reference to a change in my personal circumstances

19Aug10

When you fill out a birth certificate in Wisconsin, there’s a “Mother’s Information” section and a “Husband’s Information” section.  If you’re unmarried, you’re not allowed to put the father’s name on the birth certificate.  You have to leave it blank, and petition the State Vital Records Office after the fact to get the father included.  [...]

Filed under: baby, children   |  17 Comments
Tags: birth certificate, wisconsin

Math busking

15Aug10

Now I know what to say next time the dean asks us for some innovative fundraising ideas for the math department.

Filed under: math, offhand   |  Leave a Comment
Tags: busking

Moleeds

13Aug10

A clip of  Charles Fleischer,  a stand-up comic, wearing an endigitted blazer and performing a routine with a lot of numerology in it: I think the very first joke in this is funny and concise, but it quickly degenerates into a kind of sub-Robin-Williams “I talk loudly and quickly and change accents a lot and [...]

Filed under: comedy, math   |  4 Comments
Tags: andy kaufmann, charles fleischer, moleeds, numerology, stand-up, ted, ted talks

California prayer agency, Earth-2 Lawrence v. Texas

10Aug10

Continuing from the last post, here’s a test case for the view that judges applying the “rational basis” must defer completely to referenda. Suppose the voters of California pass a referendum instituting a state agency which employed people to pray to Jesus for the health of sick Californians.  Can a judge declare this a 1st [...]

Filed under: politics   |  3 Comments
Tags: gay marriage, law, lawrence v. texas, rational basis, strict scrutiny, supreme court

Gay marriage and the null hypothesis

10Aug10

Two controversial topics in one post! Orin Kerr this week on Perry vs. Schwarzenegger: Several of the key factual findings in Judge Walker’s opinion are in the form of predictions, not facts. For example, Judge Walker finds that “permitting same-sex couples to marry will not . . . otherwise affect the stability of opposite-sex marriages.” [...]

Filed under: bad statistics, math, politics   |  6 Comments
Tags: gay marriage, law, marriage, null hypothesis, rational basis, same-sex marriage, supreme court, walker

Turkey burgers, gazpacho, Paul Robeson

08Aug10

It’s hard to make a turkey burger taste good. You kind of need to season the hell out of it. We mixed a pound of ground turkey with a minced half-onion, a couple of cloves of garlic, an egg, and — CJ’s idea — 1/2 tsp each cinnamon and cumin.  Kind of a turkofta.  Onions [...]

Filed under: cj, food, recipes   |  6 Comments
Tags: cinnamon, cumin, gazpacho, paul robeson, tomatoes, turkofta

Show report: New Pornographers at the Orpheum

05Aug10

New Pornographers played the Orpheum last night. Boston’s “Foreplay” on the sound system before the band comes on.  Comes off as witty. On the records Dan Bejar’s singing doesn’t stand out as much as it does live.  Something about the way he approaches the microphone makes him look like he’s always about to rap rather [...]

Filed under: madison, music, shows   |  6 Comments
Tags: dan bejar, doris finsecker, fame, kathryn calder, new pornographers, orpheum