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Comment: Re: Mistake or canny PR? (Score 1) 85

by swillden (#49154075) Attached to: Google Reverses Stance, Allows Porn On Blogger After Backlash

I have a friend at Google that says the real backlash was internal, and he thinks Matt Cutts even threatened to quit over this.

(I'm a Google employee)

Internal backlash was massive, and as far as I can tell hugely stronger than the fairly mild complaints outside the company. The strength of the internal opposition took me by surprise. I understood that while Google doesn't wish to censor the web it also doesn't wish to be the entity serving up sexual content. That seems like a reasonable position to me. I thought the 30-day notice was a bit short, even though the terms of service only offer 14 days, but other than that it seemed reasonable to me, basically bringing blogger into line with the policies in place for YouTube, etc., for years.

Many of my colleagues, however, vehemently disagreed, calling it censorship, application of one region's values upon the world and generally declaiming it as the beginning of the end for Google as a force for openness and access to information. Many called the decision deeply inconsistent with Google's stated mission, "To organize the world's information and make it universally accessible and useful". The internal memegen system was awash in anti-censorship memes, and one of the memegen team went further and more or less shut the system down in protest, replacing it with a complaint about the blogger shutdown. Eng-misc, a high-volume internal mailing list for random discussions of, well, anything, was overrun with threads complaining about it. The founders got hammered with questions and complaints in the weekly company-wide TGIF meeting (which is actually held on Thursday these days, so more Googlers around the world can see it live).

It's been quite the storm.

As soon as the internal reaction started I expected the reversal, though it went further than I expected. I thought the result would just be more notice, maybe 90 days. But I suppose that's because I thought the basic decision was reasonable, and only the short notice unreasonable. Many others felt differently, obviously.

It's going to be interesting to see if this provokes re-examination of the YouTube and G+ policies. I doubt it, but I was wrong about the nature of the reversal, too.

Comment: Re:It's almost like the Concord verses the 747 aga (Score 1) 47

by swillden (#49153949) Attached to: Hyperloop Testing Starts Next Year

Actually, it's the Return on investment (ROI) that matter in business. Or in other word, how many time it'll take to make enough profit to cover the cost of the initial investment. And in this case, the US$9.95 billion California High-Speed Rail is a huge example on how much money you can make on transportation.

Using the $56 million per km quoted on California High-Speed Rail as the low estimate of how much it would cost to build a hyper loop, the minimum cost across the US would be $56 million per km * 3000 miles * 1.6 km per mile = $270 Billion dollars MINIMUM. That's going to have a hell of a long ROI, and because of that I can't see anyone in their right mind financing such a project in the near future.

Did Musk ever propose transcontinental hyperloops? I don't believe he did. As I recall this was always intended as a regional transportation technology, something for distances short enough that air travel is inconvenient because of the airport delays at both ends, but long enough that traditional train travel is too slow.

Comment: Re:Hmmm (Score 1) 47

by Rei (#49153883) Attached to: Hyperloop Testing Starts Next Year

Technically, yes, with the caveat that you'd need regular floating reboost platforms with significant power generation scattered all throughout the Pacific, and of course maintaining the track perfectly straight while floating (one presumes at a fixed depth under the water) provides its own engineering challenges. But room-temperature rarified hydrogen instead of rarified air would allow one to make the journey at about Mach 4. Faster if it's hot hydrogen.

Comment: Re:This isn't new (Score 1) 47

by Rei (#49153867) Attached to: Hyperloop Testing Starts Next Year

Are you under the misconception that hyperloop is a pneumatic tube system?

Hyperloop is a magnetically-accelerated a ground-effect aircraft operating in the sort of extremely rarified air normally only found at high altitudes. The tube's purpose is to provide such a rarified atmosphere near the ground. It's not a pneumatic train. It's not a vactrain. It's not maglev. It's a ground-effect aircraft.

Comment: Re:It's almost like the Concord verses the 747 aga (Score 1) 47

by Rei (#49153847) Attached to: Hyperloop Testing Starts Next Year

Branching would be really tricky, but there's no physical barriers. Note that even Musk's proposal isn't as far as you can take the concept. If you fill the tube with very low pressure water vapor instead of very low pressure air (via more pumping to overwhelm leaks, plus water vapor injection), your top speed jumps 40%. Fill it with hydrogen and it jumps 300% (normally hydrogen is a real pain to work with due to flammability, embrittlement, etc, but the densities in question are so low that such issues are mostly avoided). So we're talking the potential for hyperloop "speedways" for long distance runs that could blow airplanes out of the water.

The low numbers of passengers per capsule is really key to making the concept economical. Compare, say, monorail track with a full sized rail bridge. The former is vastly cheaper per unit distance because the peak loadings are so much lower, because the mass of the monorail trains are so much lower. A computer-controlled high launch rate of small, high speed capsules means you're spreading the loading out greatly, which means greatly reduced loading and thus materials costs.

Still, while Musk has been thinking of Hyperloop stations in the "airport" concept, he really needs to get out of that mindset. His proposed plan had them on the outskirts of cities. Airports are only on the outskirts of cities because they *must* be. You greatly reduce your utility by doing that, by making people catch connecting trains. Hyperloop can extend just fine into towns; with his two proposed endpoints in particular there are excellent rail routes into town that are quite straight that it could be built over.

Comment: Re:White balance and contrast in camera. (Score 1) 173

by drinkypoo (#49153513) Attached to: Is That Dress White and Gold Or Blue and Black?

pretty much every pixel in the "blue" area has a B value about 20%-30% higher than the R or G value. That, to me, makes it about as objectively blue as it's possible to be.

Are you kidding? It's possible to be balanced far more towards blue. But also, gold is not a color. I learned back in my Amiga-using, pixel-editing days that there's a lot of blue in most metallics. I don't know if that's an artifact of what happens to light when it bounces off of them, or what, sorry. Not a physicist. But I know that if you're trying to make something look metallic, you're going to be adding some blue to it.

Comment: Idiotic comparison (Score 1) 155

by drinkypoo (#49153283) Attached to: We Stopped At Two Nuclear Bombs; We Can Stop At Two Degrees.

Not only (as others have pointed out) did we not stop at two, but setting off nuclear bombs is just a thing you can decide not to do. We may well be past the point of climate runaway, and if that's so then we would have to engage in concerted effort to prevent the imminent demise of the relative condition of biostasis we've enjoyed all the time.

Or hell, maybe the next ice age cycle will solve the problem, through some as-yet-unimagined mechanism. The question then becomes whether we'll survive that.

Comment: Re:White balance and contrast in camera. (Score 3, Informative) 173

by drinkypoo (#49153269) Attached to: Is That Dress White and Gold Or Blue and Black?

The thing is, in the provided picture, the dress actually IS white and gold, or at least grey and gold. Load it up in an editor and snip pieces of it out if you don't believe me, look at them on their own, compare them to color swatches. That doesn't make the dress any particular color. It makes the picture a particular color. The "white"/"black" part is banging right around 50%, which is clearly neither white nor black.

The camera diddled the image, maybe it was diddled even more before we actually saw it. Then we're all amazed that it doesn't look like the thing. But people have accidentally been taking pictures of things which don't look like things since time immemorial. They're called shitty pictures.

Comment: Re:It's funny (Score 1) 155

by drinkypoo (#49153201) Attached to: We Stopped At Two Nuclear Bombs; We Can Stop At Two Degrees.

And neither side has any idea what to DO if they're right.

No, we know what needs to be done, we don't know how to force people to do it. And it very much takes force. The people whining about it seem to forget that this is how the world works. People with different ideas eventually come to blows because in the real world you can't do both things.


Is That Dress White and Gold Or Blue and Black? 173

Posted by timothy
from the enoy-your-lovely-ochre-sky dept. writes Color scientists already have a word for it: Dressgate. Now the Washington Post reports that a puzzling thing happened on Thursday night consuming millions — perhaps tens of millions — across the planet and trending on Twitter ahead of even Jihadi John's identification. The problem was this: Roughly three-fourths of people swore that this dress was white and gold, according to BuzzFeed polling but everyone else said it's dress was blue. Others said the dress could actually change colors. So what's going on? According to the NYT our eyes are able to assign fixed colors to objects under widely different lighting conditions. This ability is called color constancy. But the photograph doesn't give many clues about the ambient light in the room. Is the background bright and the dress in shadow? Or is the whole room bright and all the colors are washed out? If you think the dress is in shadow, your brain may remove the blue cast and perceive the dress as being white and gold. If you think the dress is being washed out by bright light, your brain may perceive the dress as a darker blue and black.

According to Beau Lotto, the brain is doing something remarkable and that's why people are so fascinated by this dress. "It's entertaining two realities that are mutually exclusive. It's seeing one reality, but knowing there's another reality. So you're becoming an observer of yourself. You're having tremendous insight into what it is to be human. And that's the basis of imagination." As usual xkcd has the final word.
It would make the comments more informatively scannable if you include your perceived color pair in the title of any comments below.

Vax Vobiscum