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Comment Re:Anonymous Coward (Score 1) 66

Midshipmen majoring in Computer Science at the US Naval Academy (my major and alma mater, class of '00) are indeed cognizant of Admiral Hopper, though I don't think there's anything specifically that teaches about her contributions. Part of this (and here I start to hypothesize) is the relative age - ADM Hopper's contributions, though extremely important and noteworthy, are relatively recent, in comparison to the rest of what goes on at USNA - the goal is, after all, to provide highly technically-trained graduates to drive ships, not go on to academic careers. Much of the infrastructure and heritage stems from the people and events of the Revolutionary War (aka "War for American Independence") through World War II, heavily favoring the mid- to late-1800's. Operational topics before and after that (and during, to give meaning and context to the heritage) are taught in classroom settings. But though ADM Hopper's contributions to the field of computer science are important, at best it's the contributions that are taught (not the name), and definitely not in an operational context (she spent her entire career as a reservist and rarely was operational).

Weylin

Comment Re:How can a black hole emit anything? (Score 3, Informative) 145

Several other comments talk about a pair of particles being created out of nothing, one gets absorbed and the other flies away. This is basically right, but can be confusing (the one that gets absorbed has negative energy in order to conserve energy). Here's an easier mental model....

Steve Hawking came up with an idea a while ago (70's perhaps?). He was thinking about black holes whose event horizon was around the size of an atom. Then he put it up against the Heizenberg Uncertainty Principle. He realized that particles in these black holes would have such a high degree of certainty about their position, that there would be such a low certainty about their velocity. Therefor, there would be some that would be REALLY fast. Not fast enough that they could escape the pull of the black hole, but fast enough that they could get just above the event horizon. There, they could give off a high-energy photon, and fall back in. This photon, since it was emitted outside the event horizon, would actually escape. This radiation can (and has been) detected, and causes what is known as evaporation. http://en.wikipedia.org/wiki/Hawking_radiation#Black_hole_evaporation

Ironically, this means that smaller black holes (which have higher certainty about a particle's position) evaporate faster. Large-ish black holes absorb more energy cosmic microwave radiation than they emit in Hawking radiation, but if they have small enough mass (I believe smaller than the size of our moon), they emit more Hawking radiation than they receive from the cosmic background.

Idle

ThinkGeek's Best Ever Cease-and-Desist Letter 264

ThinkGeek, sister company to Slashdot, received a meticulously researched (except on one point) 12-page cease-and-desist letter from the National Pork Board. What had the meat lobbyists up in arms was an April Fools product from the TG catalog: Radiant Farms Canned Unicorn Meat, whose copy included the line "the new white meat." The NPB figured this was confusingly similar to their trademarked "the other white meat" (an advertising slogan the pork industry is considering retiring anyway). Geeknet, parent company of Thinkgeek and Slashdot, issued a press release apologizing for any confusion; you can read it on ThinkGeek's site (PDF), because the newswires refused to distribute it for some reason. Oh, and ThinkGeek has no intention of taking down the protected parody.

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