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Comment Sloppy's One Rule of Robotics (Score 1) 129

My one rule of robotics (and pointed sticks, cars, crackpipes and umbrellas) is this: my stuff ought to perform in accordance with my wishes.

There might be additional laws ("weld here and here, but nowhere else," or "use the rules in /etc/iptables/rules.v4" or "don't shoot at anyone whose IFF transponder returns the correct response") which vary by whatever the specific application is, but these rules aren't as important as The One above.

There are various corollaries that you can infer from the main law, but since they can be derived, they don't need to be laws themselves. (e.g. if my interests conflict with someone else's, then my robot and my umbrella ought to serve my interests at the expense of the other person's interests.)

With regard to harming other robots, that also can be derived. If I desire to kill a knight on a robot horse, then my robot ought to turn them into a pile of bloody gore and shredded circuitboards immediately. OTOH, if I don't desire to kill a robot, then my robot should not do things that incur unnecessary liabilities.

Science

Scientists Create Permanently Slick Surface So Ketchup Won't Stay In Bottle 172

HughPickens.com writes Much of what we buy never makes it out of the container and is instead thrown away — up to a quarter of skin lotion, 16 percent of laundry detergent and 15 percent of condiments like mustard and ketchup. Now Kenneth Chang reports at the NYT that scientists have just solved one of life's little problems — how to get that last little bit of ketchup (or glue) out of a bottle. Using a coating that makes the inside of the bottle permanently wet and slippery, glue quickly slides to the nozzle or back down to the bottom. The technology could have major environmental payoffs by reducing waste. Superhydrophobic surfaces work similar to air hockey tables. Tiny peaks and valleys on the surface create a thin layer of air between the liquid and the coating. The air decreases friction, so the liquid almost levitates above the surface, just like the hockey puck floats above the table. LiquiGlide's approach is similar, but it uses a liquid lubricant, not a gas. "What could be a solution that provides sort of universal slipperiness?" says Dr. Varanasi. "The idea we had was, Why not think about trapping a liquid in these features?" Dr. Varanasi and Mr. Smith worked out a theory to predict interactions among the surface, the lubricant and air. Essentially, the lubricant binds more strongly to the textured surface than to the liquid, and that allows the liquid to slide on a layer of lubricant instead of being pinned against the surface, and the textured surface keeps the lubricant from slipping out. "We're not defying physics, but effectively, we are," says Smith.

Comment Tom Clancy strikes again (Score 1) 341

Tom Clancy published 'The Sum of All Fears' in 1991. In the afterword, he mentions how it was frighteningly easy to piece together, from public domain data, how to build a multistage thermonuclear bomb. How he was couriered design specs for fabrication devices for the asking. How he felt the need to obfuscate some details, even though he knew there was no point, just to assuage his conscience.

As he points out, it's physics, and it's engineering.

Censorship

Indian Supreme Court Strikes Down Law Against Posting 'Offensive' Content Online 54

palemantle writes: The Indian Supreme Court has overturned the controversial Section 66A of the IT Act which included a provision for a three-year jail term for sending "offensive" messages through a "computer resource or a communication device." In its judgement, the Supreme Court held "liberty of thought and expression as cardinal" and overturned the provision (66A) deeming it "unconstitutional." It's been in the news recently for an incident involving the arrest of a high school student for posting allegedly "offensive" content on Facebook about a local politician.

Comment Re:I'm probably missing something (Score 1) 417

The Central Valley of California is sitting on rich topsoil over 100 feet deep. Before the modern water projects, it mostly grew winter wheat, because there's enough moisture in winter (the rainy season in California) for that in most years. The Central Valley is technically a Mediterranean climate, not a desert (though the southern part of the Valley is technically semi-desert). But the water projects made it profitable and possible to grow crops year-round rather than just in the winter, mining that 100 feet of topsoil for food. Telling people they can't mine a resource like that doesn't go down well with Americans, who tend to be an ornery sort.

Comment More expensive water can mean more water usage (Score 1) 417

An example is almonds. Almonds now use close to 10% of water used in California. One almond takes approximately 1.1 gallons of water to create it.

So: Why, in the midst of drought, are California farmers planting *more* almonds? The answer, paradoxically, is because water has become more expensive. The water projects are not delivering water to California farmers, so California farmers have a choice between a) not growing crops (and thereby losing their farm, since no crops means they can't pay the mortgages they took out on their farm equipment and/or farmland to expand in earlier more optimistic times), or b) drilling wells. Drilling wells that in some cases are a thousand feet or more deep. The water from these wells is ridiculously expensive for two reasons: 1) the simple cost of drilling, and 2) the large amount of electricity needed to haul that water (at 8 pounds per gallon) up that 1,000+ feet of pipe to the surface.

In fact, the water from these wells is so expensive that if the farmers used it to grow a low-water-use crop like wheat they'd lose money. Most low-water-use crops like wheat or corn have a relatively low price on the commodities market, a price that will not pay for the cost of the well and the electricity to pump water out of the well. So, paradoxically, expensive water has caused farmers to instead grow almonds -- one of the only crops that sell for a higher price than the cost of the water needed to grow them, yet also one of the most water-thirsty crops on the planet.

And now you know the side of the story you don't get from the Libertarian free market think tanks and their notion that expensive water would cause water usage by farmers to decline. What matters to farmers is *not* the absolute cost of the water. What matters to the farmers is the *marginal* cost of the water -- the difference between what it costs to obtain the water, and what income they get from using the water. When water was cheap but in limited supply, farmers grew crops that were water-thrifty because the price of those commodities was enough to pay for the water. Now that water is expensive but they can pump as much as they wish from the ground (until the aquifer runs dry, anyhow!), the California farmer's slogan becomes "drill, baybee, drill!" and the almond trees go in.

Comment Re:End the Fed! (Score 1) 160

Not to mention that many diseases were a death sentence in 1913. Sure, health care was cheap. The doctor would take a chicken in trade; but all he had was a black bag. Appendicitis? surgical mortality was much higher. Polio? No vaccine. That's why FDR was in a wheel chair. Today? We can even cure some cancers if we catch them in time. Yeah, paying premiums sucks. I just paid mine today. Hate it; but I have no desire to go back to 1913.

Comment The design is relatively simple (Score 2) 341

The design of the bombs is not the problem. Getting fissile material to build the trigger is the problem. Even a large corporation could probably not enrich uranium without attracting attention. Unless the book contains some method that Joe Sixpack can use to leach highly-enriched uranium from tailings or something, it's not a threat.

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