Interesting. Thanks.

They also pass through airplane skins, presumably. But I wonder how many of the particles that pass through airplanes and tape will also be intercepted by sensors?

I suppose the only answer needed is "enough to calibrate against."

Sorry to be dense (ahem), but why "of course" are they transparent to gamma radiation? Gamma particles have high frequencies, and so more energy, but doesn't the short wavelength make them prone to being absorbed (all other things being equal)?

IINAP, so I could well be wrong about that, but that was my understanding.

Here's the thing: not only does entanglement not sent information faster than light, it doesn't send any information at all. Nothing that happens on your end affects the particle at the far end. You've learned something about the particle at the far end by doing the experiment, but only about properties it possessed before the particles were separated, not about anything that happened to it after the fact.

Now, you have to be very careful here, since the "property" I'm talking about is a quantum property, not a classical one. It is explicitly NOT a "hidden variable" whose value was set but unknown. The two particles existed in a superposition, not in one state or the other, but both, and it won't take on a single state until interacted with a larger system. But that interaction doesn't put information into the particle, and no information is transmitted to the other side, at the speed of light or otherwise. It's almost as if they end up in complementary states when measured by coincidence.

That's weird, but only because we insist on trying to understand it in classical terms which simply don't apply. Taken on its own terms, it's well-understood and well-demonstrated that no communication occurs, nor would it be expected to occur, since that would violate a number of other physical principles that also seem rock-solid. There's no reason to think it would ever allow FTL communication, since there's no communication at all, and that's unlikely to change.

I hadn't realized that the Vandals objected.

These particular devices are not meant for human interfacing or running a UI, but for the Internet of Things(really hate that name) and ubiquitous computing.

I share your loathing for that name. The fact is, these are intended for ubiquitious governance, where everything from a baby rattle to your keychain is a governance device designed to monitor, track, and someday soon record your every action and movement.

The price at which we'll all be willing to sell out to this level of surveillance and control? The convinience of being able to find our car keys whenever we lose them, and monitor our babies without a baby monitor. Do it for the children, and to protect yourself from terrorists! Welcome to the future, where we are all chattel of the state, and there is no getting away.

It gets worse once you have more than one password to remember. The silly image tries to link them all together, so that you don't get your "correct horse battery staple" mixed up with your "blender green lobster carburetor" at your bank and your "mango bookbag tooth bitter" for your work computer, but if you've left any of them alone for more than a few weeks they fade and get mixed up. "Correct horse battery staple" stands out by itself from your eight-letter passwords for being different, but as part of a whole password ecosystem the advantages diminish.

In the end, I think that entropy is entropy. Trying to use visual mnemonics to handle more entropy is an old (and helpful) trick, but the XKCD example isn't a good one: three of the four words appear as words. Only the horse shows up solely as a horse; only the "battery staple" really connects two separate words together visually.

"Memory castles" work because they tell a story, and they're for memorizing stories. But they're not all that good at memorizing them exactly, letter for letter, which is the point of a pass phrase. And when the elements of the story truly are random, they don't evoke each other. To provide real continuity you'd need to turn your four words into a full story, and now you're memorizing lots of extra bits to make them cohere.

This isn't a terrible idea; passwords are hard. But it's not the automatic win that Munroe makes it look like. You simply won't be able to keep hundreds of bits of entropy in your head without flaw unless you practice them over and over. And if you practice over and over, you can do just as well with "Tr0ub4d0r" as anything else.

It's not just a hypothesis. It's a hypothesis that fits some data, from GPS satellites and the Juno probe. It's solid enough to present as an idea to other scientists.

It's not solid enough to present as an idea to the general public, but unfortunately that's what popular science publications do for a living. They want "news"; their readers want to be the first ones to hear about exciting new developments. So they publish highly speculative material without the kinds of caveats, qualifications, and context that other scientists in the field bring automatically.

I have a love-hate relationship with them. They're helpful in drumming up public interest in science, playing up the romantic parts that help young proto-scientists engage with the field before the years of drudge work that go into actually becoming a scientist. And they help keep people feeling good about science and voting to fund it. But they mis-inform as much as they inform, and real scientists are continually having to provide the context that the magazines frequently refuse to.

(New Scientist is better than most daily newspapers, but worse than Science News. Frequency of publication seems to make a big difference: the longer your readership is willing to wait for accurate information, and the less they demand to have it ten seconds before the next guy, the more informative they are. Web-only sources are generally the worst.)

That would be saying a LOT.

I hate to sound like an old complainer (especially not to somebody with a five-digit Slashdot ID), but it really does feel as if the site has become rather calcified in its opinions. I used to read it more for the comments than the articles; they were generally more informative. I feel like I rarely learn anything from the comments any more; they're all largely the same and they're generally predictable without my having to read them.

It's not universally true, which is why I still come here, but I'm finding less and less reason.

And then document where you put the document...

I was a teen sereval teen-cycles ago, and the 1st idiot wearing Glass that I meet will need a good medical team, no discussion, period.
Tech is great, but in the current climate of mistrust this is a bad, bad idea and technology.

Do it to me, and your wages will be garnished for life. You'll be buying me a new airplane if you so much as touch me. It's a public place, they're free photons buddy, and I'm not the government. Get over it.

You want to go after someone, go after the NSA, or the credit bureaus, or the many, many assholes already selling every aspect of your life you think is secret. Don't go after your fellow citizens who now, at long last, are starting to get the technology that levels the playing field and allows them to in turn start watching the watchers.

Absolutely, this has the potential to completely redesign the way we look at manufactured products. That goes well beyond China; it would radically disrupt the economy at home, too. A lot of products that are currently shipped could be printed.

I think the case of books is instructive, though. For a long time we've had the technology to print books at home. DRM was of course an issue, and publishers weren't jumping at the chance to make the book available to print, but even setting that aside I think people who want printed books would generally rather have them mailed rather than downloaded and printed on their own printer. There are little things, like binding, page size, and the price of printer ink. In the end, the Kindle disrupted that market before it got going.

I suspect we'll find that for a lot of common products, we'll want to keep doing it the old-fashioned way until somebody completely disrupts the market. I don't know what that will look like. I do know that I'm about to go buy a new coat, and can't imagine the day coming any time soon when I'd download it and print it.

Not really. Right now it looks as if the "collapse of the universe" is a "never" thing that never gets any closer. The value of the cosmological constant seems to be greater than 1.

This paper isn't about that, but about an even more obscure idea involving the false vacuum that gives rise to the Higgs field. It's a wildly speculative theory to succeed the Standard Model. That theory has a different kind of collapse involving a radical change to the Higgs field, greatly increasing the mass. This paper doesn't bring it any closer in time; rather, it's one (tiny) step closer in understanding the theory.

As far as I can tell, we're a long way from that, mostly because "printer supplies" would require such a wide array of materials.

3D printer can make shapes, but as far as I can see they're not very good with materials. They take what they get. A gun as the advantage of being a block of metal; all it needs to be is strong. But even something as simple as a kitchen spatula or frying pan would prove quite complicated. The spatula head needs to be flexible, while the handle needs to be stiff. A decent frying pan is actually quite a complex bit of manufacturing, using multiple layers of metal to conduct heat while remaining stiff and scratch-resistant. A great many things require specific types of plastic or metal, which is easy enough to do when the Chinese will make ten million of them, but harder to imagine for a one-off.

I don't doubt that these are problems that will be solved some day. At least some of them will be solved by completely reinventing the task and the tool, rather than trying to adapt new technology to the old job. But I'm really not expecting to give up my Amazon Prime account any time soon.

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How does one adequately thank a person who provided exactly the right help and encouragement at exactly the right time in a young man's life resulting in a family supporting career and income? Even two wives (nobody's perfect) and daughter owe you a thank you.

While I have fond memories of a few key teachers in some classroom settings, I can firmly point to that Radio Shack purchase of my copy of your "Engineer's Notebook" in 1977 as the real start of my career in Electronics-to-Computers-to-SoftwareEngineering.

I suppose the obvious answer is "Pay it Forward". While I have recommended your books to techno-curious young people I have met over the years, what else can and should be done?

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The vendors sure do. Or at least, they'll imply it as hard as they possibly can without the FDA catching up to them.