Edge: An interesting site

Here's an interesting site to peruse at one's leisure. I've bookmarked on my toolbar so I'll see it most days.

Enjoy.
(hat tip: Ilachina)

Brian Hayes on Complexity

Brian Hayes, a columnist for American Scientist magazine, gives a wonderful blog entry about the complexity and its confusing use of strange, often weird, terminology.

My concern here is not with the difficulty of the concepts—there’s not much we can do about that—but with the notation and terminology. Do locutions like P^#P and NISZK and (NP ∩ coNP)/poly roll trillingly off your tongue? How about EXP, EEXP, NEXP, PEXP and SUBEXP? And while we’re on the subject of EXP and friends, I’ve been wondering how to pronounce NEXPTIME. (I’m kind of hoping the “P” is silent, as in Pterodactyl.)

And it gets even better:

The sad truth is, the naming conventions for furniture at Ikea make for a more consistent language than those of complexity theory.

Read it all, just for fun.

Invisible tank

In secret trials last week, the Army said it had made a vehicle completely disappear and predicted that an invisible tank would be ready for service by 2012.

The new technology uses cameras and projectors to beam images of the surrounding landscape onto a tank.

A soldier, who was at the trials, said: "This technology is incredible. If I hadn't been present I wouldn't have believed it. I looked across the fields and just saw grass and trees - but in reality I was staring down the barrel of a tank gun."

I have believed for years that this was possible. Years ago I hypothesized such an invention with fiber optic cables where images from one side of an object would be "transmitted around" the object. That was fanciful and people I told about it where less than impressed. Still the idea nagged at me. But using cameras with projectors, if that's how this is actually, done, makes sense. The technological hurdles must be substantial.