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March 26, 2007

Auction Theory

Anything less than a first-place finish based on your own statistics really has to be considered a screwup.

March 26, 2007 Comments (0) TrackBack (0)

March 21, 2007

Ferries always have right of way

You really don't want to stress a moose out. They're much bigger than you.

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March 20, 2007

Shell Game

A ruse that relies on the target's innate acceptance of the rules presented to him? Against a league of paladins? Easy money.

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March 11, 2007

Landau

Is the Landau "Theoretical Minimum" published anywhere? (by preference, in English)

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Continuity equations

The project is wrapping up. To keep my brains from going into my feet, I've been reviewing Aitchison & Hey.

I stared at problem 4.1 until I was stupid. Or maybe I started that way. Does anybody get that far into relativistic QM without having it burned into their souls that taking the complex conjugate of an expression reverses the order of the operators?

In other words, if we start with:
AΨ = 0
then we know that another way we can spell this is
Ψ AΨ =0

Further more, we can take the transpose of the first equation:
(AΨ) =0

and multiply on the right
(AΨ)Ψ =0

Now all the fiddly bits do what they are supposed to, and you don't find yourself staring at things like Ψ V Ψ† wondering how you are supposed to know if that commutes or not. You take the difference, and the real bits fall out, and the imaginary factors do sensible things, and the main difference between the two is that the operators act on other things, and right answers just start raining down from the sky.

At least, that's what happened when I tried it. 'course, the text gave me a pretty clear understanding of what answer I was supposed to get; it is possible that my progression from the problem to the solution is completely lacking in local logical continuity.

March 11, 2007 Comments (0) TrackBack (0)