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## Comment Re:Speed of gravity? (Score 1)325

It's not instantaneous, because the LIGO detectors saw a delay. You can't specifically say what the speed was because the delay depends on the speed and direction. But the detection is consistent with a wave travelling at the speed of light from a source in the southern sky.

## Comment Re:Anyone can answer? (Score 1)325

From various observations (and the theory of general relativity) we're pretty sure gravity propagates at the speed of light. You find gravity everywhere because it's already there, the same way that walking from a dark room into sunlight doesn't imply that light travels from the sun to your eyeballs instantaneously.

If the sun were suddenly dematerialized you would continue to see sunlight for another eight minutes. We are also fairly sure that the Earth would continue in it's orbit as if nothing had happened for eight minutes, until the gravitational effects of the disappearing sun had time to propagate.

## Comment Re:Cool! (Score 1)325

Since Newton we've made a variety of observations that we're fairly sure imply gravity propagates at a finite speed. If that's true, it's very difficult to construct a theory that doesn't include waves. Realistic MOND theories (i.e. more than just "GR is wrong.") include gravity waves, although they might disagree with relativity about how easy they are to detect.

## Comment Re:Cool! (Score 1)325

There's no way we're going to focus gravity waves any time soon. But (I think) you could build a gravity wave interferometer. LIGO effectively IS sort of a gravity wave interferometer right now, with the baseline between the two sites giving it the ability to determine the rough direction to the sources. If you wanted to build up an image you'd need a lot of LIGOs, but it would be possible. And awesome.

## Comment Re:Michelson-Morley were wrong. Ether exists (Score 2)325

We detected the electromagnetic ether a long time ago. Today we call it "the photon field." If we had a quantum field theory of gravity we'd call the gravity ether "the graviton field" but instead we settle for calling it spacetime.

## Comment Re:Self-Selection? (Score 5, Interesting)274

First impression: somebody needs to learn about statistics that have more than one predictor variable.

Second impression: despite the lack of appropriate analysis, the differences in figure 5 are big enough to be reasonably clear. It looks like there is discrimination against anybody who has a gendered profile (maybe maintainers don't like pictures?). This discrimination might be slightly greater against outside women, and is fairly likely greater against inside men.

Third impression: the paper and the Slashdot summary have a strong gender bias; they mention only the small and borderline significant anti-female bias while ignoring the more significant anti-male bias and also the much larger anti-(either) gender identifiable bias.

## Comment Re:Just a thought... (Score 1)274

I believe he was trying to say "practically insignificant." It's a necessary companion to statistically significant, where you look at the size of the effect and decide whether it makes any difference or not, even if it is true.

I haven't read the article so I don't know if he's right, but his general point is good. The p-value isn't the only thing that matters.

## Comment Re:Hmmm ... Czar? (Score 1)298

"It's like some idiot heard a cool word, and then next thing you know everybody is a freaking czar of something. "

I expect it's not like that at all. It is that. Exactly.

## Comment Re:Advertising ROI (Score 1)276

When a significant number of people cut their (ad supported) cable and subscribe to Netflix (no ads), then ad supported programming is decreased. All the stuff about the channels pandering to their audience may be true, but it's irrelevant. Note that, despite the existence of Hulu (apparently, I'm in Canada) Netflix continues to expand. There is a growing market for ad-free television.

The super bowl is a special event that happens for a few hours every year. Yes, ads for the super bowl cost a lot. But they also cost a lot last year. We don't know how well an ad-free Super Bowl would do, because it simply aren't offered that way. The super bowl is also a bit of a special case because the ads cost so much that advertisers put more effort into making them entertaining. How well would an ad-free Netflix-like sports service do against regular ad supported sports?

## Comment Re:Solution: static ads from 1st party (Score 1)276

It works just fine. I have a friend who streams. He has sponsors who pay him to endorse their product to his small audience. The sponsor watches his viewer numbers and those come into play when they renegotiate. I know of several niche websites that do similar things: instead of just slapping up a Google ad they make deals with relevant sponsors and show their ads.

Web ad services are so successful because a) they're the lazy solution for both advertisers and hosts and b) they give the marketers low effort data so they can say "see, we're all quantitative!"

## Comment Re:Advertising Bubble (Score 2)276

Many studies have shown that much of the financial system is essentially random. It's just that everyone else is making random decisions too, so the pigeons all do their dances. There was one study that actually had monkeys pick stocks. They did as well as professional traders.

Then there are the actual criminals, of course. Such as those who manage IPOs.

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