Your Friendly Neighborhood Mathematician

Hue Knew?

2009-12-06T04:39:36Z

A (age 3½): Daddy, do you know that chameleons can change their color?
me: You're right, they can!
A: Is that because they have rainbows inside them?

Overachiever

2009-10-20T00:34:55Z

Surely a new entry in the annals of bedtime procrastination should be made for "Daddy, I can't go to sleep, there's dirt behind my ears!"

Oops Tenenbaum?

2009-08-03T04:03:39Z

So Joel Tenenbaum admitted he'd done all the file sharing the RIAA accused him of, and all the judge asked the jury to decide was the size of the monetary damage. They found him liable for a total of $675,000 for the 30 songs — kind of an arbitrary number, don't you think? Check out this observation passed on by David Post at the Volohk Conspiracy:

One interesting little aspect of the judgment: The jury awarded the record companies $675,000 in damages — $22,500 for each of the 30 songs on which the suit was based. As my colleague James Grimmelmann of NY Law School has pointed out, that's a curious number for the jury to have chosen. The statutory damage provisions of the Copyright Act (17 USC sec. 504) allow a jury to award damages of $750 (minimum)to $30,000 (maximum) for each work infringed (which can be raised, or lowered, by the judge in certain circumstances). The minimum amount that the RIAA could have been awarded, then, would have been a total of $22,500 ($750 x 30 songs). Could it be they got mixed up, and instead awarded plaintiffs $22,500 for each song? Why else would they have chosen that amount? Strange ...

Man, that would make for great numerology, wouldn't it? And yet, it sounds like there's good evidence against this, from a comment on the blog by Ben Sheffner:

I was in the courtroom for the trial, including the reading of the verdict. When the number was announced, I, too, initially thought there might be a mistake, that the jury meant to award the minimum of $750 per work, and that the $22,500 was supposed to be the total award.

However, Judge Gertner said very clearly that the $22,500 was per work, and she asked the jury whether that was accurate. They collectively said "yes." Also, I spoke with one of the jurors shortly after the verdict. From that conversation, I am very confident that the $22,500 per work figure was not an accident or mistake.

So much for that...

"That periodical contained neither guns nor ammo."

2009-07-18T03:40:18Z

Let Us Now Praise Awesome Dinosaurs.

Thanks for the pointer, rifmeister.

Fortune Favors the... Huh?

2009-06-29T02:15:47Z

We had a pleasant dim sum lunch at Green Tea today — ordering off a menu, not hunter-gatherer style, but tasty nonetheless. And then came the fortune cookies for dessert, in which, I kid you not, A. received:

"The rubber bands are heading in the right direction." What?!

Of course, in this day and age, we're not the only one: Google currently reports about 116 hits for that exact phrase, and it's the second auto-complete suggestion when you type "the rubber b" into the Google search box.

None of the links I followed up made it any less baffling, though...

The Naming of Things

2008-12-06T04:07:51Z

I love watching language acquisition in kids. A, now two and a half, still provides occasional gems.

So he's been reading D's old copy of A Pocket for Corduroy, with D's name (written in 4-year-old block caps) inside the front cover. We read the name to him the first time, and now that he knows what it says, every time he opens the book he points out to us "That spells Daniel!"

And then the other day D. was in the room — and A. opened the book, and said "Look, Daniel, that spells you!"

Sixth Sheik's Sixth Sheep's Sick

2008-08-14T15:28:47Z

"List ten things you like beginning with a letter" meme, caught from ruthling. She gave me S.

Sour pie cherries — this year, all of a sudden, available fresh in stores near you! Yum!
Socializing. Thursday night dinner is a high point of my week.
Shakespeare. I'm sad that we missed "As You Like It" on the commons this year.
1729
Storms, with thunder and lightening. I think "lack of thunderstorms" was my only complaint about the weather in Berkeley. Adam howls in terror of thunder, unfortunately, which has made them less fun this summer.
Sierpinski Gasket, my favorite fractal.
Sleep. Good stuff. I should do it more.
Semi-colons! I love 'em, even if they do get beat up on these days.
(Jonathan) Strange and Mr. Norrell. Wasn't that a great book?
Sex. Heh.

Want a letter?

WTF?

2008-08-06T02:18:37Z

Oh man, I so don't get this cartoon from the current New Yorker.

Anyone with even the slightest clue?

"I have to see it in type"

2008-07-15T17:56:08Z

In 1992, I was an undergraduate math major, and I had just learned a mathematician's second language: LaTeX, the universally-adopted typesetting system. All of a sudden, I could do my math homework in latex, print it on a laser printer, and it would come out looking like — well, just like my math textbooks did. It was remarkable, but in a way it was disturbing. On the one hand, any theorem that looks that good surely must be true, which is a dangerous way to feel. And on the other hand, once I'd gotten past that, it was daunting: what do I have to say that deserves to look that good?

By contrast, I'm sitting in a book talk by Salman Rushdie, who's here at Google giving a reading from his new novel The Enchantress of Florence and answering questions. In the context of talking about how technology has changed his writing process, he mentioned that his notes are all in longhand in notebooks, but the actual writing all happens on a computer, and was typing before that. "I have to see it in type," he just said. "I can't tell whether it's any good, if it's in my handwriting; I always think it's either better than it is or worse than it is."

Underground Elephant!

2008-05-22T14:46:24Z

And many more, at http://www.animalsontheunderground.com/the_animals.html

"Let's see, a qubit... I used to know what a qbit was..."

2008-04-16T13:36:03Z

Okay, sometimes I'm way behind the current events. But how cool is it that there's a website from which you can download free truly random bits — created one at a time from quantum fluctuations?

And better yet, when you sign up, they include a novel captcha: an image of a randomly-generated latexed math formula you have to solve. Mine involved differentiating trig functions...

Arrrrgh

2008-03-03T03:02:14Z

Aggravating game of the evening: http://onemorelevel.com/game/spin_the_black_circle

I've made it to level 17 so far...

Nudge, Nudge...

2008-01-12T21:00:18Z

I must have read today's Arlo & Janis half a dozen times before I finally got it.

Is it extreme on the subtle-o-meter, or is it just me? (Or, of course, do you not get it?)

French Hens

2007-12-26T01:33:42Z

Passed on from a post by my brother bkleber:

I Have a Little List

2007-12-11T04:22:02Z

I usually admire the work of copy editors: many of my published articles have benefited greatly from their attention. But the journal for which I'm an editor/columnist has a new copy editor starting this issue, and he is... let's call it "overzealous." I admit that written mathematics is a tricky thing to edit, doubly so if you're not a mathematician yourself. But still:

I wrote a sentence of the form [Foo] is the unique nontrivial example of [Bar]. Editor helpfully decided it would read better with an added comma, and claimed that [Foo] is the unique, nontrivial example of [Bar]. Now all of a sudden my sentence is claiming that [Foo] is the only example, and what's more, it is nontrivial.
I wrote that two sets of points "are quite similar: you can convert one to the other by moving a single point." Editor doubtless felt that "quite similar" was the kind of phrase Strunk and White warn you against, and deleted the word "quite". But this magically converts "similar" from a casual adjective to a mathematical technical term, like the "similar triangles" from 9th grade geometry: the two sets are absolutely not similar!

I hope I've caught everything, and that no other sentences have casually had their meaning drastically changed. I sure hope "they'll none of them be missed"...

Chain Factoid

2007-12-03T04:45:23Z

So I was all pleased with myself earlier today, when I scored a personal best of 271,392 on Chain Factor — thanks, ams16, quite an addictive little game. That score was, at the time, good for 6th place today and 64th place all-time.

But now I see where I really stand:

All-time High Scores (Basic Mode)

1	grr+1	492,553
⋮
5	grr+1	403,223
⋮
21	grr+1	315,250
⋮
35	grr+1	288,936
⋮
67	mk	271,392

Okay, G., you take the cake, as usual...

Post-Tang Let-Down

2007-10-21T13:42:47Z

Adam was talkative this morning. The first words out of his mouth might have sounded, to the untrained ear, like "bi'klat", but to those of us in the know he was clearly smiling broadly and saying "big light!" This was rapidly followed by a sad "no big light?" and, very shortly, by a strident "want big light!" (The big light in question, of course, was the multicolored light machine from the Tang Party last night.)

And in case there was any lingering doubt as to which of Adam and Lillian belonged to which parents: Both toddlers had their first Tang last night. Lillian came back for another sip, then another; afterwards she pushed away her normal sippy-cup and wanted Tang instead. Adam took one sip of Tang, looked up at me, and said "water!"

Puzzle thingy

2007-09-11T18:30:03Z

If you like on-line math-y puzzle kind of things, check out Bloxorz. Clever.
Note to self: I'm at passcode 284933

Ghastly Tribbles

2007-09-05T01:48:57Z

If you haven't seen Shaenon ("Narbonic") Garrity's vision of Edward Gorey does Star Trek, you're missing a gem.

No, I'm not quite sure why I didn't post for all of August.

Corpus, Corpus, I Hardly Even Know Us

2007-07-29T01:01:38Z

There's a delightful "On Language" piece in this weekend's NYT Magazine. It's on the Oxford English Corpus: don't look in a dictionary to see what a word means; look at how it's actually used!

(Though I can't keep from mentioning this: how you devote yourself to understanding the way words work, and at the same time produce the ambiguous sentence "Information from the O.E.C. can show us the way to better dictionary entries"? Is that "better" an adjective or a transitive verb?!)

Up With Which I Shall Not Put For

2007-06-30T02:14:44Z

Dear Professor X,

Enclosed please find a complimentary copy of the book, Y, of which you contributed an article for.

Sincerely,
The Z Association of America

Wowitty wow wow wow.

2007-06-14T03:05:01Z

Seen on Volokh, this incredible presentation from TED (q.v. for larger view). Now that's how to pull information together!

Powers

2007-06-01T15:56:06Z

At this point I pretty much assume everyone reads xkcd (complete with LJ feed xkcd_rss), but there are some gems in today's comments.

Original:

Variant by meeve:

Variant by gryphonthepure:

Google The Transformer

2007-05-20T03:14:48Z

Long-time readers may recall the ongoing legal proceedings in Perfect 10 v Google, which I wrote about last year. This was the case in which a web site that sold nude photos sued Google for copyright infringement, because third-party web sites were violating P10's copyright of those images, and Google's image search indexed those third-party sites. The interesting bits are all about fair use.

Recall that "fair use" is not defined by any bright-line criteria; courts have to weigh various factors: the purpose and character of the use, the nature of the copyrighted work, the amount of the work used, and the effect on the potential market all come into play. Google ran into trouble on the shoals of potential markets: P10 had a business deal that involved selling low-resolution thumbnailesque versions for use as cell-phone backgrounds.

The district court issued an injuction becuase they felt Google would probably lose their fair use claim. On Thursday the 9th circuit disagreed (full text here). Google always had the "purpose and character of the use" factor on its side: the thumbnail use for indexing and searching is "transformative," clearly different from the intended use of the original image. It turns out that the use is, well, very transformative:

We conclude that the significantly transformative nature of Google's search engine, particularly in light of its public benefit, outweighs Google's superseding and commercial uses of the thumbnails in this case. In reaching this conclusion, we note the importance of analyzing fair use flexibly in light of new circumstances. (“[Section 107] endorses the purpose and general scope of the judicial doctrine of fair use, but there is no disposition to freeze the doctrine in the statute, especially during a period of rapid technological change.”) We are also mindful of the Supreme Court's direction that “the more transformative the new work, the less will be the significance of other factors, like commercialism, that may weigh against a finding of fair use.”

The parties have to go back to the lower court to squabble about whether Google did enough in response to P10's telling them about the infringing sites; if Google failed to take simple measures to help protect P10's copyright, there might be a contributory liability claim. But the fundamental right to index things has been upheld.

First Theorem

2007-05-14T02:05:47Z

D. has been learning-slash-playing-with multiplication lately, and has enough place-value fu that yesterday he got 81*9=729, once he realized that 80*9 is 800-80, not 800-8.

So the other day he asked me, "What's 12 squared? Oh, is it just 10 squared plus 2 squared?" I drew him this picture, and he completely understood what was going on — and promptly calculated 12², 13², and 15², just to prove it.

Since he understood it so readily, I just couldn't resist: I told him he was ready to learn his first theorem. He already knew what a right triangle was — from second grade math class, even! — so he had no trouble understanding the statement of the theorem in the form "the two smaller squares' areas add up to the area of the big square." And we were already half way through my favorite picture proof:
He understood it immediately, with just the right kind of smile.

And then came the best part: he asked the question I hadn't even realized I was hoping he would. For parents in most professions, this would not be a singular moment. But my kid asked me, with just a hint of wonder in his eyes, "Daddy, how did someone think of the idea of drawing those diagonal lines?" And I got to tell him, "That is what mathematicians do."