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Comment Re:Randomness can't come from a computer program (Score 1) 64

Most of us do have a need to transmit messages privately. Do you not make any online purchases?

Yes, but those have to use public-key encryption. I am sure of my one-time-pad encryption because it's just exclusive-OR with the data, and I am sure that my diode noise is really random and there is no way for anyone else to predict or duplicate it. I can not extend the same degree of surety to public-key encryption. The software is complex, the math is hard to understand, and it all depends on the assumption that some algorithms are difficult to reverse - which might not be true.

Comment Re:Bad RNG will make your crypto predictable (Score 2) 64

The problem with FM static is that you could start receiving a station, and if you don't happen to realize you are now getting low-entropy data, that's a problem.

There are many well-characterized forms of electronic noise: thermal noise, shot noise, avalanche noise, flicker noise, all of these are easy to produce with parts that cost a few dollars.

Comment Randomness can't come from a computer program (Score 2, Interesting) 64

True randomness comes from quantum mechanical phenomena. Linux /dev/random is chaotic, yes, enough to seed a software "R"NG. But we can do better and devices to do so are cheap these days.

I wouldn't trust anything but diode noise for randomness. If I had a need to transmit messages privately, I'd only trust a one-time pad.

Robotics

Video Making a Birdhouse is Like 'Hello World' for a Versatile Factory Robot (2 Videos) 24

Many millions of American students have been called on to construct a wooden birdhouse as part of a middle- or high-school shop class. To make a birdhouse from wood and nails may not requite advanced carpentry, but it does take eye-hand coordination, object recognition, the ability to lift constituent pieces, and to grasp and wield tools -- and each of those can be broken down further into smaller tasks and skills of the kind that we as humans don't generally have to think about. ("Rotate wrist slightly to account for board angle.") For robots, it's another story: like the computers that run them, robots generally only do what they're told. Industrial robots can do some complex tasks, but they're expensive and complex to program.

Benjamin Cohen is a Ph.D candidate at the University of Pennsylvania working under adviser Maxim Likhachev with a real-world, cheap way to make robots to accomplish a multi-step project with minimal human intervention, which he calls "autonomous robotic assembly." Project Birdhouse -- part of his Ph.D. work, along with teammates Mike Phillips and Ellis Ranter -- is Cohen's effort to create a sort of "Hello, World" for robots. With a combination of a research-platform robot base, off-the-shelf parts, like a nail gun (read: "One not built for robot use"), and software to squeeze greater accuracy out of the system as a whole, he and his colleagues have come up with a robot that can grab a selection of parts, align them properly, and assemble them with nails into a functional birdhouse. QR codes let the robot give the robot a sort of recipe to follow, and the system is smart enough to squawk if it doesn't have the right parts to complete the task. (Check out more video with the robot in action, and a great many photos, sketches, and diagrams illustrating the project's evolution.)

NOTE: We split today's video in half, with both halves running right here, today. This way, if you watch the first video and and want to learn more, you can move on to the second one. And the transcript not only covers both videos, but has "bonus" material that isn't in either one.

Comment Re:I'm spending 60% of my monthly income on rent (Score 4, Insightful) 940

Maybe you should learn what communism is before calling anyone "commiefriend". (Which I have to say, is really repulsive. It's sort of like picking your nose over the internet.) I think you are discussing the difference between lasiez-faire ecomomics and regulated markets. Communism is a very great difference in scale from that. And it's never been tried on a national scale just as "free market" has never been tried because there are always economic biases that make it impossible. What there has been so far is socialism.

Comment Re:I'm spending 60% of my monthly income on rent (Score 1) 940

I think you're missing the fundamental economic issue that drives all of this. It's the provision of essentially infinite amounts of credit. This is done by government, not banks. Essentially all home loans come from Fannie Mae or Freddie Mac, banks and finance companies are really just front-ends for them and sell their loans to the government once financed.

Given infinite credit, any scarce but necessary resource is going to be bid to absurd values.

It is by no means being a hippie to assert that government should not distort the market for credit, and to expect that urban and suburban land values would return to more realistic rates once the distortion was removed. Too bad that lots of people have already invested in unrealistic land values. They would have to lose.

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