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Comment Re:Energy density (Score 1) 361

It's there, but we have to put an absurd amount of relatively rare resources into photovoltaic cells to make *use* of that energy.

You have peculiar notions about what solar cells are made of.

By weight, a finished monocrystalline solar panel is primarily silicon, 2nd most abundant element in Earth's crust, followed by aluminum, 3rd most abundant element in Earth's crust. The n-dopant that is half of what makes the silicon a semiconductor is phosphorous, 11th most abundant element in Earth's crust. The p-dopant that is the other half of what makes the silicon a semiconductor is boron, 41st most abundant element in Earth's crust, considerably more common than beryllium or tin, somewhat less common than lead. There is a tiny bit of silver on the upper surface, as a conductor, 65th most common element in Earth's crust, and the only remotely rare element in the list. Fortunately it is used in proportion to its rarity, so it's not a limiting factor to speak of.

In short, solar panel production is not in any way material limited. The Earth is made of the necessary elements, almost in the proportions they are used. There is enough of the necessary materials available to plate the entire surface of the Earth in solar cells, oceans included.

Fortunately no such excess is necessary. A population of 20 billion could enjoy the average per-person energy availability of an American without covering an appreciable fraction of the Earth's surface in solar panels, and you couldn't tell the difference in terms of the material used.

Comment Re:Bullshit (Score -1) 697

su is not only for root. it has a dual purpose: switch user or super user. Sometimes you might have to run a command as another user. So if you need to login as Gary you $su gary and type in Gary's password.

Yes, but not quite. If you need to login as Gary, you $su gary and type in your password. You never know Gary's password.

Unless you're using systemd su. Then I suppose maybe you do have to demand Gary's password. That sounds like something Poettering would think up.

Comment Re:And so it begins (Score 3, Interesting) 179

There should be pushback. But there won't be pushback.

In North Dakota? A machine points a weapon at them with no visible human, you can bet North Dakotans will shoot back, and they won't be shy about using lethal weapons. This is practically an invitation to a skeet-shoot. Any reluctance to fire at law enforcement simply doesn't exist when it's nothing but a buzzing flying thing. Even if it's a larger one, if it's low and slow enough to employ a non-lethal weapon successfully, it's GOING to get shot down, repeatedly. Yeah, you'll be brought up on charges. It won't stop people, no matter how much of an example they make of the first few.

Comment Re:I don't think K-12 CS is a good idea anyway (Score 1) 184

If a girl can improve her reading comprehension and strengthen her vocabulary by reading trashy novels...

If? Have you actually read one of those things? I have, basically on a dare, and I was assured by the woman who issued the challenge that it was typical of the genre. And there will be no vocabulary strengthening from trashy romance novels. They're apparently written using the apocryphal 700 words that newspapers are supposed to use. Wielders of extended vocabularies, they are not. With the exception of being excellent sources of synonyms for "breasts" and "penis". Somehow I don't think the children would have any trouble picking those up on their own, so I'm thinking the trashy novel is not a big win.

Comment Re:They are missing a perfect opportunity... (Score 1, Informative) 67

They are missing a perfect opportunity to conduct testing on the effects of alcohol on the human body while weightless!

You do realize half the station personnel at any time are Russian, right? And that they get a personal baggage allowance? Which is inspected by other Russians? That was practically the first experiment conducted on the human body in space, aside from just living and breathing.

Comment Re:It's a prototype (Score 1) 107

To be fair, it was kind of a funny comment. All someone has to do to get +5 is read the article, summarize the relevant points, and suddenly you are the most knowledgeable guy in the room because no one reads the articles.

With good reason. Half the time the article is wrong, either in whole or in part, and you have to read six other things too before you really have any understanding of the topic.

For years, the summary was usually insanely wrong. Diametrically opposed to the linked article. It was bizarre. I'm convinced it was Slashdot editor policy to pick the worst possible article summary submission for the front page in order to drive comments correcting it. So yeah, you had to read the comments to find out what was actually said (because you weren't going to read the article, because it was wrong anyway).

Comment Re:I'll Wager (Score 2) 64

$5 says that the 600MHz spectrum gets sold to cell companies.

You plebs don't need a $50 WiFi router that can reach a mile away.

If it was for sale, then you'd get your $5. But it's not. "Whitespace" spectrum is unlicensed, limited use of existing licensed spectrum which will not change hands. This is what Google has been after since the 700 MHz auction in 2008. The existing licensed users (OTA TV stations) stay in place, and maintain priority. But they're not using all of the spectrum in every major market, and there are very few licensed users in rural areas. All of that empty spectrum (minus guard bands around the licensed users) can be used ad hoc by transmitters that obey the power caps.

This ruling makes available TV channels 2 through 51 for the general public, as long as there is no incumbent licensed user. In practice, that means rural users could get lots of bandwidth. City users in the most crowded television markets get almost nothing.

Earth

Climatologists: By 2100, the Earth Will Have an Entirely Different Ocean 417

merbs writes: The ocean is in the midst of radical, manmade change. It can seem kind of crazy that one of the most immense properties on Earth—the ocean washes over 71 percent of the planet—could be completely transformed by a swarm of comparatively tiny, fleshy mammals. But humans are indeed remaking the ocean, in almost every conceivable way. The ocean we know today—that billions swim, fish, float, and surf in—that vast planetary body of water will be of an entirely different character by the end of the century: hotter, higher, trashier, and more acidic.

Comment Re:Relativity (Score 5, Informative) 199

Time dilation isn't proven, otherwise we wouldn't have been able to see anything.

What are you babbling about? The GPS system has detailed time dilation compensation built into it. It's not only proven, it has to be accounted for in the engineering of a functioning system in worldwide use.

GPS satellites are moving at 14,000 km/hr relative to Earth's surface, a Special Relativity time dilation of 7 microseconds per day. But Earth-based clocks are deeper in the gravity well of Earth, so they suffer a General Relativity time dilation of 45 microseconds per day. The nanosecond accurate clocks on board the satellites are pre-calibrated before launch to tick more slowly than they should while on Earth, so once in orbit, they tick at a General-Relativity-time-dilation-compensated rate that then matches Earth clocks. The software still has to compensate for any additional, unpredictable drift caused by orbital variances.

Time dilation is quite real, and must be accounted for, or GPS and Galileo wouldn't work at all. Uncompensated clock error amounts to 10km on Earth per day.

Comment Re:It's already happened before. (Score 1) 168

Which is absolutely stupid- Marvel has shown that they know how to do superhero movies and that they are willing to play ball to get control back (look at the deal they made with Sony for Spiderman). They'd be happy to do the same for Fantastic Four. The problem is the same studio owns XMen, and doesn't want to lose that cash cow.

So presumably sometime around 2020, we'll see Marvel Studio do Fantastic Four. Hugh Jackman is quitting as Wolverine. He'll be in the next X-Men movie, and in one more Wolverine movie, and then he's done. Which, given that he'll turn 50 before the last Wolverine movie comes out, is hard to hold against him. But it means the end of X-Men being a cash cow.

Yes, Patrick Stewart and Ian McKellen have done fantastic jobs, but neither Professor X nor Magneto are the main draws for X-Men. It's going to be extremely difficult to recast Wolverine, and I pity the actor who tries. Hugh Jackman has made the role his own.

Basic is a high level languish. APL is a high level anguish.

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