## Edith Wharton shipped Esther/Haman

That theory, now, that Odysseus never really forgot Circe; and that Esther was in love with Haman, and decoyed him to the banquet with Ahasuerus just for the sake of once having him near her and hearing him speak; and that Dante, perhaps, if he could have been brought to book, would have had to confess to caring a good deal more for the pietosa donna of the window than for a long-dead Beatrice — well, you know, it tallies wonderfully with the inconsequences and surprises that one is always discovering under the superficial fitnesses of life.

(Edith Wharton, “That Good May Come,” 1894.)

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## If you build it they will come and exploit it

There’s no way to build a program for people in need that can’t be taken advantage of by unscrupulous people who aren’t in need. I have a friend, an attorney, who used to work cases involving people who defrauded the foster care system, taking state money for the care of children who didn’t exist, or who weren’t really in their care. It’s maddening. She eventually quit that job, partially because it was so dispiriting to come in daily contact with people being awful. But what can you do? You can’t build a fence strong enough to keep out all fraud without making the administrative burden impossibly high for the many honest people doing the hard, humane work of raising kids who need parents. There’s some optimal level of vigilance that leads to some optimal level of fraud and that optimal level of fraud isn’t zero.

I thought of my friend when I read this story, about developer Dan Gilbert getting an “opportunity zone” tax break officially intended for spurring development in impoverished areas:

Gilbert’s relationship with the White House helped him win his desired tax break, an email obtained by ProPublica suggests. In February 2018, as the selection process was underway, a top Michigan economic development official asked her colleague to call Quicken’s executive vice president for government affairs about opportunity zones.

“They worked with the White House on it and want to be sure we are coordinated,” wrote the official, Christine Roeder, in an email with the subject line “Quicken.”

The exact role of the White House is not clear. But less than two weeks after the email was written, the Trump administration revised its list of census tracts that were eligible for the tax break. New to the list? One of the downtown Detroit tracts dominated by Gilbert that had not previously been included. And the area made the cut even though it did not meet the poverty requirements of the program. The Gilbert opportunity zone is one of a handful around the country that were included despite not meeting the eligibility criteria, according to an analysis by ProPublica.

Maybe there’s no way to design a program like this without billionaires with phalanxes of lawyers and friends in high places being able to sop up some of the money. Even before the “opportunity zones,” Jared Kushner was able to game a similar program by drawing a gerrymandered “low-income district” that snaked its way through Jersey City to include the site of his luxury skyscraper and also some poor neighborhoods miles away. But I have to believe the optimal enforcement level is higher and the optimal malfeasance level lower than what we have now.

Ward 49 and Ward 66 are two big voting precincts in Madison. Ward 65, where I vote, has 2.819 registered voters. Ward 49, in the campus area with tons of undergrad-heavy high rises, has 3,505.

In the 2018 governor’s race, Ward 65 went for Tony Evers 2190-179. Ward 49 also went big for Evers, though not as dominantly: he won there 1985-591.

Now look at the April 2019 Supreme Court election. Ward 65 went strongly for the more liberal candidate, Lisa Neubauer, voting for her by a 1631-103 margin. Ward 49 also liked Neubauer but the margin was 531-101. 25% more voters but about a third as many votes. Evers narrowly won his election. Neubauer narrowly lost hers. Young voters sitting out downballot elections is pretty important.

## The real diehard

Yesterday a guy saw my Orioles hat and said, “Wow, you’re a real diehard.”

He was wearing a Hartford Whalers hat.

## "Hamilton"

We saw the last show of the touring company’s visit to Madison. The kids have played the record hundreds of times so I know the songs very well. But there’s a lot you get from seeing the songs realized by actors in physical space.

• I had imagined King George as a character in the plot interacting with the rest of the cast; but in the show, he’s a kind of god/chorus floating above the action, seeing certain things clearly that the people in the thick of it can’t. So his famous line, “I will kill your friends and family to remind you of my love,” comes off in person as less menacing, more cosmic. Neil Haskell played the role very, very, very mincy, which I think was a mistake, but it got laughs.
• On the other hand, I hadn’t grasped from the songs how big a role George Washington plays. It’s set up very nicely, with the relation between Hamilton and the two Schuyler sisters presented as a shadow of the much more robust and fully felt love triangle between Hamilton, Burr, and Washington.
• The biggest thing I hadn’t understood from the record was the show’s gentle insistence, built up slowly and unavoidably over the whole of the night, that the winner of a duel is the one who gets shot.

## The Americans can retire at 42

On the front page of my New York Times today, this capsule summary:

The French can retire at 62. Or 52. Sometimes 42. President Emmanuel Macron calls the tangle unsustainable. A million protesters disagree.

In the actual article, we learn that the retirement age of 42 applies to one group of workers; dancers in the national ballet. I find it very annoying when an article is teased with a number presented as normal when it’s actually extremely atypical. You could write the same teaser about the United States, having New York City firefighters in mind. But you would be misleading your audience even though the claim would be, I suppose, technically correct.

## Shocking the carrots

It takes a long time to soften carrots adequately by sauteing them, so a lot of recipes ask you to boil the carrots first or even mix butter and water and cook the carrots in the resulting lipidous slurry. This ends up tasting OK but the carrots never really taste sauteed to me, they taste boiled! I want that sear.

So this week I tried something new, borrowing a technique I learned a long time ago for perfect sauteed asparagus. Put your butter in the pan, melt it, get those carrots sauteing in there. Put in some salt and whatever other seasoning you want at whatever time suits that seasoning. (Dill is traditional, I used nutmeg this week and it was great) Saute the carrots until they’re nicely browned. At this point they will not be cooked enough. Eat one, it’ll taste nice on the outside but still be crunchy and part-raw.

So now it’s time to shock the carrots. Fill a small drinking glass half-full with water. So maybe a quarter cup, I dunno. Throw the water in the hot pan and immediately, as the sizzle kicks in and the steam begins to rise, slam the lid on. It should sound sort of like a high hat when you crash and then right away mute. Turn the heat down and let the carrots steam in there for about six minutes. When you open it, the water should be gone but if it’s not I would just take the carrots out with a slotted spoon. Result: fully tender carrots that taste sauteed, not boiled.

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## Khot,Minzer,Safra on approximate sections of sheaves

Subhash Khot is giving a talk at Current Developments in Math this year and his talk has the intriguing phrase “Grassmann graph” in it so I thought I’d look up what it is and what he and his collaborators prove about it, and indeed it’s interesting! I’m just going to jot down something I learned from “Pseudorandom Sets in Grassmann Graph have Near-Perfect Expansion,” by Khot, Dor Minzer, and Muli Safra, in a way that makes it sound like something algebraic geometers might be interested in, which, indeed, I think they might be!

Suppose you have a sheaf F on a space, and the space has a covering U_1, .. U_N. The sheaf axiom says that if we have a family of sections s_i of F(U_i) such that s_i and s_j agree on $U_i \cap U_j$ for all i,j, then there is actually a global section s in F(X) which restricts to each s_i.

What if we only have an approximate section? That is: what if we have a family of s_i such that: if I select i and j uniformly at random, the probability that s_i and s_j agree on $U_i \cap U_j$ is bounded below by some p > 0. Call such a family a “p-section.” (You should take the view that this is really a family of problems with X changing and N growing, so that when I say p > 0 the content is that p is bounded away from some 0 uniformly in X,N.)

The question is then: Is an approximate section approximately a section?

(This is meant to recall the principle from additive number theory that an approximate subgroup is approximately a subgroup, as in e.g. Freiman-Rusza.)

That is: if s_1, .. s_N from a p-section, is there some actual section s in F(X) such that, for i chosen uniformly at random,

$\mathbf{Pr}(s | U_i) = s_i > p' > 0$

for some p’ depending only on p?

The case which turns out to be relevant to complexity theory is the Grassmann graph, which we can describe as follows: X is a k-dimensional vector space over F_2 and the U_i are the l-dimensional vector spaces for some integer l. But we do something slightly weird (which is what makes it the Grassmann graph, not the Grassmann simplicial complex) and declare that the only nonempty intersections are those where $U_i \cap U_j$ has dimension l-1. The sheaf is the one whose sections on U_i are the linear functions from U_i to F_2.

Speculation 1.7 in the linked paper is that an approximate section is approximately a section. This turns out not to be true! Because there are large sets of U_i whose intersection with the rest of X is smaller than you might expect. This makes sense: if X is a space which is connected but which is “almost a disjoint union of X_1 and X_2,” i.e. $X_1 \cup X_2 = X$ and $\latex X_1 \cap X_2$ involves very few of the U_i, then by choosing a section of F(X_1) and a section of F(X_2) independently you can get an approximate section which is unlikely to be approximated by any actual global section.

But the good news is that, in the case at hand, that ends up being the only problem. Khot-Minzer-Safra classify the “approximately disconnected” chunks of X (they are collections of l-dimensional subspaces containing a fixed subspace of small dimension and contained in a fixed subspace of small codimension) and show that any approximate section of F is approximated by a section on some such chunk; this is all that is needed to prove the “2-to-2 games conjecture” in complexity theory, which is their ultimate goal.

So I found all this quite striking! Do questions about approximate global sections being approximated by global sections appear elsewhere? (The question as phrased here is already a bit weird from an algebraic geometry point of view, since it seems to require that you have or impose a probability measure on your set of open patches, but maybe that’s natural in some cases?)

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## Pete Alonso was a Mallard

Pete Alonso of the New York Mets is the NL Rookie of the Year and the all-time home run king among both rookies and Mets. I’m proud to say I saw him hit a 407-foot three-run moonshot in June 2014, when he was a 19-year-old playing for the Madison Mallards in the summer-collegiate Northwoods League. Go Mallards!

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## Los Angeles, November 2019

Actually, I arrived on October 31, but who can resist a gratuitous Blade Runner reference?

I was in town for the always-interesting meeting of the IPAM science board. Keep an eye on their schedule; there are great workshops coming up!

There was chaos and anger at LAX when I landed, because the airport just this week moved Lyft/Uber/taxi pickups offsite. For reasons I don’t fully understand, this has led to long waits for rideshare cars. For reasons I understand even less, people are waiting an hour for their Lyft to show up when the regular taxi stand is right there, and you can — I did — just hop in a cab with no wait and go. (Yes, a VC-subsidized Lyft is cheaper than a cab, if it’s not surge time. But the bus is cheaper still, and once you’re not saving time with the Lyft, what’s the point?)

So I got in my cab and went to the beach, and watched the sunset over the ocean. Clear view of a really nice Moon-Jupiter conjunction and Venus still visible down at the horizon. Last time I went to Dockweiler Beach I was all alone, but this time there were several groups of people in Halloween costumes around bonfires. That was probably the most Blade Runner thing about this trip and it wasn’t even November 2019 yet!

I have a first cousin in LA, and good luck for me — my first cousin’s first baby was born my first morning in town! So on Saturday after the meeting I got to go see my first cousin once removed on his second day alive. I haven’t seen a one-day-old baby in a really long time! And it’s true what they say; I both remember my own kids being that age and I don’t. It’s more like I remember remembering it. I thought I was going to have a lot of advice but mostly all I had to say to them was that they are going to be amazing parents, because they are.

The hospital was in East Hollywood, a neighborhood I don’t know at all. Walking around afterwards, I saw a sign for an art-food festival in a park, so I walked up the hill into the park, where there wasn’t really an art-food festival, but there was a great Frank Lloyd Wright mansion I’d never heard of, Hollyhock House:

As with most FLW houses, there’s a lot more to it than you can see in the picture. A lot of it is just the pleasurable three-dimensional superimposition of rectangular parallelipipeds, and that doesn’t project well onto the plane.

There were a lot of folks sitting on blankets on the hillside, even though there was no art-food festival, because it turns out Barnsdall Park is where you and your 20-something moderately hipster friends go to watch the sunset in LA (unless it’s Halloween, in which case I guess you dress up and build a bonfire on Dockweiler Beach.) Sunset:

Then I ate some Filipino food, since Filipino restaurants sadly don’t exist in Madison right now, and went back to my hotel and read MathJobs files.