The Packbats' Weblog

How Likely is a Random Universe to Produce Your Twin?

2010-09-18T19:51:08Z

Dan Shive (best known as the creator of El Goonish Shive) recently wrote a brief argument why alternate universes would probably not contain alternate "you"s. His argument looks correct, as far as it goes, but it is qualitative - lacking numerical estimates - and I don't see why it has to be. The data exists. Surely ballpark back-of-the-envelope numbers could be produced.

...but not trivially. Dan Shive's challenge can - and I think should - be broken down as follows.

( Read more... )

Now, I lack the knowledge of biology to, first, nail down these questions to their most correct forms, and second, assign probability estimates to relevant steps in the chain. But the most superficial examination of the situation seems to suggest at least one thing: any alternate universe measurably diverging a significant period before the birth of an individual is vanishingly likely to contain a copy of that individual. Which, of course, is what Dan Shive has pointed out.

And, as an obvious consequence of this, even if such a universe contained a duplicate of yourself, it would still be vanishingly unlikely for it to contain duplicates of anyone not your direct descendant. (Which would make for a heck of a paternity test, I have to tell you!)

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STS-124 Launch: Solid Rocket Booster Video+Audio

2010-08-24T16:44:59Z

Via egypturnash. Video is a bit monotonous for first two minutes, but the wait is worth it.

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Amateur Science of the Week: xkcd Color Survey

2010-05-06T23:12:06Z

The breakdown is here, if any of you missed it. I find most of these results fairly unsurprising (although the "yellow" region of the saturated color space contains a startling amount of green), but it's really cool to read through the details anyway. Favorite bits:

The mnemonic* for how to spell "fuchsia".
"Actual color names if you're a [girl/guy]..."
The list of colors.
The entire "Miscellaneous" header.
"Baige".

* Fun fact: I instinctively put a "u" after that "e". Perhaps you can guess how I pronounce that word...

(P.S. Word up, Mr. Munroe.)

(P.P.S. I'm feeling much recovered, save for residual sleep-dep from catching up on grading.)

(P.P.P.S. Less Wrong taught me a lot more about teaching than I expected.)

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