Feeds:
Posts
Comments

Archive for December, 2009

Sun glints off a lake of methane on Titan

NASA image used with permission.

Sunlight reflects off a methane lake on Titan, Saturn’s largest moon. Holy wow. The lake is called Kraken Mare, and it’s in Titan’s northern hemisphere, which began to come back into daylight in August after 15 years of night. (This pic was taken July 8 by the Cassini spacecraft.) All this according to NASA’s release today. Haze on Titan scatters most light in the visible spectrum, so this is an infrared photo. And Titan is very cold. So Kraken Beach Cabanas aren’t going to be a resort spot for a while.

Advertisements

Read Full Post »

As I’m wrapping up my Christmas shopping for this year, I wanted to share a photo of a gift I made last year: an Othello game board for my Dad. Isn’t this a pretty piece of African mahogany? (It cost $8!)

Dad taught me to play Othello when I was a little girl and I have finally got to where I can beat him occasionally. You’re constantly turning over the little pieces in this game, so I knew I wanted to make them out of some really nice woods that would be a pleasure to look at and hold; I chose cocobolo and quilted maple. Then I started trying to cut the discs… with a hand drill. That lasted about 45 seconds. I began to utter unprintable words — I needed to cut out 128 of these little goobers. And the only person I know with a drill press is my dad!

So I asked at the exotic-wood lumberyard, and they sent me to a nice guy named Bob who’s a cabinet-maker and craftsman. He took on the job of cutting all those little discs.  I baked him oatmeal cookies.  Then I sanded all 128 of the blasted things and joined them up (each gamepiece is light on one side, dark on the other).  I sewed a little bag to hold them, also.  The gameboard was mostly a job of careful grid layout, then cutting the dowels to length and notching them so they fit together. My first real work with chisels and files. Good learning project.

Dad and I have already enjoyed numerous games.  He says I did a good job on it.  I know I certainly put a lot of love into it.  And of course, I didn’t have an opportunity to mess up because my work was closely supervised as usual by Bradley.

Read Full Post »

Yesterday had been widely touted as an opportunity for some snow, a rarity in our area. Journalists, of course, keep a wary eye on the weather, because the worse it gets, the more important it is that people know what the eff is going on. People come in early, stay late and all hands are needed on deck. (Pretty much no matter how yucky the streets get, you’re coming in to work.)

So it was really a relief that yesterday turned out to be a bust, freezing-precip-wise. Though we would have adored some snow. I sent my parents this description of a part of our morning, and since my mom was kind enough to say it was funny, I’ll reproduce it here. Of course, she is my mom.

On her way out to her car to pick up our (Friday lunch run), (my coworker) called from the parking lot to say there were flakelike articles in some of the air. News staff rushed to windows, squealed in glee. The flurry strengthened for several minutes but never once attained any white on the ground or indeed anything you could tell was a snowflake by visual inspection, except that they kind of fluttered instead of just dropping straight down.

A minute ago I went back to the window and sadly reported the flurry was over.  Everyone asked for details, and I said, “Well, I don’t see anything coming down that looks like snow.”  Everyone was bummed.  Then I stood there watching for a few minutes… and then suddenly hollered “FLAKE!”

The newsroom howled with laughter (me too, of course) and I got the expected comments of “Yeah, I see a flake too!”

Your eye on the weather, that’s me.

Read Full Post »

Yesterday’s NYT had a very interesting story about biologists discovering evidence that humans are naturally helpful to each other — very young humans, before our parents presumably whap it into us.  Of course if we didn’t cooperate to some degree we’d have croaked long ago… and if we weren’t kind of warlike, we wouldn’t have survived either.

It all puts me in mind of a “game theory” strategy that I once read was the most useful: Begin by cooperating, but as soon as your opponent does not cooperate, retaliate. This applies to a lot of areas, obviously, but grew out of a very specific problem used in philosophy and now played out by computers in programming tournaments: the prisoner’s dilemma.

Basically, in its various versions, the dilemma is this: You and another person are in a situation where you each must choose to cooperate or to betray each other. You don’t know what the other will do. If you both cooperate, you get a great reward; if you both betray, neither gets a reward. If one cooperates and one betrays… the betrayer gets half the reward.

Any pair of siblings, roommates or lovers will recognize the scenario. When one does all the taking and one does all the giving, misery ensues – though only for the giver. The taker does just fine. Mutually assured destruction comes to mind also: We hoped the Russians loved their children too.

Douglas Hofstadter, in whose “Metamagical Themas” I first read about the dilemma, introduced me to the idea that the game is different if you know you’re only going to play once, versus expecting to have to continue to deal with the same opponent in future. If you only play once, you are better off betraying. But if you both expect to deal with each other again, the game changes.

Hofstadter described the first programming tournament on these lines, and says it was won by an incredibly simple program called Tit For Tat, which simply did whatever the opponent did right back to it. If its opponent always cooperated, then so did Tit For Tat. If its opponent defected (betrayed), Tit For Tat retaliated – once (whereas some programs strategically would keep defecting every time once “trust” was broken). But if Tit For Tat’s opponent cooperated again, it would cooperate again.

Hofstadter writes, “(Tournament architect Robert) Axelrod’s technical term for a program for a strategy that never defects before its opponent does is nice. … Note that ‘nice’ does not mean that a strategy never defects! Tit For Tat defects when provoked, but that is still considered being ‘nice.’ ”

The chapter goes on to explain how Axelrod defined several characteristics of Tit For Tat’s success. TFT was “nice,” but also “provocable” — that is, it would retaliate if provoked; it wasn’t always nice — and “forgiving.” Some strategies that did even better added a fourth: “clarity,” a kind of ability to analyze when the opponent’s behavior wasn’t making any sense. When that happened, they switched to pure defense.

Axelrod, and after him, Hofstadter, are careful to warn against drawing any too broad conclusions.  I note the New York Times article says the researcher claims that “inductive parenting,” defined as explaining to kids why they logically stand to gain from cooperating, is best. (Good luck with that.) He doesn’t mention that a well-timed retaliation, followed by forgiveness – and backed up by the wisdom to realize when you’re mired in a losing game – can be really useful too.

Read Full Post »