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.
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.)
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.
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.
Well... up until now, airplanes have been reasonably peaceful and quiet. It's been that way for so long that I think it is reasonable to expect it.
As for earplugs... they're not really all that effective. They're good for dampening certain kinds of noise, but it's far from silent. Even with earplugs in you're going to have no trouble making out the conversation of the person next to you, and that's going to remain distracting.
I really don't believe that legislation is the answer here. I think there are a lot of alternatives to try first. But this is going to make some people happy at the expense of making a lot of other people very unhappy, and in considering where we go from here I'd ask the people in the former category to not put all of the burden on the latter.
However, AdS/CFT tells us nothing about our universe, since we know that the type of string theories it talks about can't describe our universe.
Is that because AdS corresponds to a negative cosmological constant, and as far as we can tell the cosmological constant is positive?
This has always confused me. Why are they working in AdS at all? I figured it was because the math was easier, and they were hoping to reach a point where they understood it well enough to flip around the sign of the constant and get the "real universe" back. Or... maybe I have no idea what I'm talking about, so I apologize if what I just said was gibberish.
Actually, I was given bloodletting for a while as a treatment for a rare blood condition (hemochromatosis). It came in the form of blood donations. Obviously this is completely different from the "bleed them until they faint and figure it's progress because they've stopped screaming" kind of bloodletting, but I found it deeply ironic.
Five bucks a week, for All of the Internet... still a price a lot of people would pay to be truly free of ads and the tracking that goes with it. (At least, until they started finding ways to scam it; I'd be reluctant to let sites have direct access my money, even if only a limited pool of it. And of course it's a whole new way to track you, since there's some kind of line from the web site to the account to the way you fill that account.)
Reading the comments I eventually got enough context to track down the Wikipedia entry, which says: "drag racing tires perform better at higher temperatures, and a burnout is the quickest way to raise tire temperature immediately prior to a race. They also clean the tire of any debris and lay down a layer of rubber by the starting line for better traction."
So... is this just for drag racing? Or is there some other point to this?
Change minds? Nah. But it's fun. Because the paranoid delusion is there whether you feed it or not, and no amount of pandering to them is ever going to make it go away.
This is decidedly not what Gandhi would do, nor MLK. But neither of their opponents were as ravingly delusional as the Oppressed American Christian, who can be neither reasoned with nor shamed. That which cannot be defeated must be borne, which we'll do with laughter, until the declining numbers that power the ferocity of their paranoia make them politically irrelevant. That, and the intermittent sanity of the courts to protect us from the far more real oppression that they want to impose, are the only ways we can cope.
True. Though he could also have just substituted "people", which would have fit the grammar without the additional connotation of smug condescension, and the irony of repeating a mantra while pretending to be an independent thinker.
As you say, it's well used, and I do know exactly what it means: that somebody is about to tell me how much better he is than everybody else, with very little justification. In that sense, he was being helpful. And in exactly that sense I was trying to be helpful by pointing out that he might get his intended message (the one about whatever it is we're talking about, rather than the one about his self-superiority) across better if he didn't start out with name-calling that doesn't even have the benefit of originality.
I enjoy imagining you spluttering as you're writing this, gradually realizing that you've got nothing to contribute and finally remembering the caps lock button. Thanks for making my day.
Calling it a "law" is an exaggeration for comic effect. But it gets that name because it's common enough to be a recognized trope, indeed overused: you can make a headline more exciting by hinting that a development is more important or that a trend is more pervasive than it actually is. Stories that are important in and of themselves generally have statements rather than questions in the headline.
Invoking Betteridge's Law may well itself be an over-used trope, but if it is it's only because there's so very, very much call for it. News aggregators like Slashdot serve as concentrators, seeking out the most exciting stories. Ideally, the editors would serve as filters as well, recognizing exaggerated headlines and either ignoring them or putting them back into proper context. Instead, it's usually left to a poster to do that, generally after a lot of excited and/or outraged posting based on the headline. (Because the posters who just read the headline will always get there before people who bothered to RTFA.)
And you're going to demonstrate your independence by reiterating a weak pun that's well worn enough to have both a Wikipedia entry (which notes its "shrill and excessive use") and an XKCD already in place?
But it's worth noting that the converse is not true: not all unreasonable people make progress. Unreasonable people would ideally consider whether they're actually achieving something, or just being assholes.
Unfortunately, by definition that's something an unreasonable person cannot do. So the world ends up sorting through self-congratulatory dipsticks, hoping to find the smallish fraction who actually merit congratulations.
Slashdot Mirror
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.
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...
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.
no one ever really claimed that multivitamins would just flat prevent cancer
The vendors sure do. Or at least, they'll imply it as hard as they possibly can without the FDA catching up to them.
Well... up until now, airplanes have been reasonably peaceful and quiet. It's been that way for so long that I think it is reasonable to expect it.
As for earplugs... they're not really all that effective. They're good for dampening certain kinds of noise, but it's far from silent. Even with earplugs in you're going to have no trouble making out the conversation of the person next to you, and that's going to remain distracting.
I really don't believe that legislation is the answer here. I think there are a lot of alternatives to try first. But this is going to make some people happy at the expense of making a lot of other people very unhappy, and in considering where we go from here I'd ask the people in the former category to not put all of the burden on the latter.
However, AdS/CFT tells us nothing about our universe, since we know that the type of string theories it talks about can't describe our universe.
Is that because AdS corresponds to a negative cosmological constant, and as far as we can tell the cosmological constant is positive?
This has always confused me. Why are they working in AdS at all? I figured it was because the math was easier, and they were hoping to reach a point where they understood it well enough to flip around the sign of the constant and get the "real universe" back. Or... maybe I have no idea what I'm talking about, so I apologize if what I just said was gibberish.
Actually, I was given bloodletting for a while as a treatment for a rare blood condition (hemochromatosis). It came in the form of blood donations. Obviously this is completely different from the "bleed them until they faint and figure it's progress because they've stopped screaming" kind of bloodletting, but I found it deeply ironic.
Five bucks a week, for All of the Internet... still a price a lot of people would pay to be truly free of ads and the tracking that goes with it. (At least, until they started finding ways to scam it; I'd be reluctant to let sites have direct access my money, even if only a limited pool of it. And of course it's a whole new way to track you, since there's some kind of line from the web site to the account to the way you fill that account.)
I didn't realize that there were even that many people. It's almost literally a ghost town on weekends.
Honestly, living in the US, I'd be content with just the occasional break from the partisan lunacy, even if only the moment of silence.
Wow, are you still on about this?
Reading the comments I eventually got enough context to track down the Wikipedia entry, which says: "drag racing tires perform better at higher temperatures, and a burnout is the quickest way to raise tire temperature immediately prior to a race. They also clean the tire of any debris and lay down a layer of rubber by the starting line for better traction."
So... is this just for drag racing? Or is there some other point to this?
Change minds? Nah. But it's fun. Because the paranoid delusion is there whether you feed it or not, and no amount of pandering to them is ever going to make it go away.
This is decidedly not what Gandhi would do, nor MLK. But neither of their opponents were as ravingly delusional as the Oppressed American Christian, who can be neither reasoned with nor shamed. That which cannot be defeated must be borne, which we'll do with laughter, until the declining numbers that power the ferocity of their paranoia make them politically irrelevant. That, and the intermittent sanity of the courts to protect us from the far more real oppression that they want to impose, are the only ways we can cope.
True. Though he could also have just substituted "people", which would have fit the grammar without the additional connotation of smug condescension, and the irony of repeating a mantra while pretending to be an independent thinker.
As you say, it's well used, and I do know exactly what it means: that somebody is about to tell me how much better he is than everybody else, with very little justification. In that sense, he was being helpful. And in exactly that sense I was trying to be helpful by pointing out that he might get his intended message (the one about whatever it is we're talking about, rather than the one about his self-superiority) across better if he didn't start out with name-calling that doesn't even have the benefit of originality.
I enjoy imagining you spluttering as you're writing this, gradually realizing that you've got nothing to contribute and finally remembering the caps lock button. Thanks for making my day.
Calling it a "law" is an exaggeration for comic effect. But it gets that name because it's common enough to be a recognized trope, indeed overused: you can make a headline more exciting by hinting that a development is more important or that a trend is more pervasive than it actually is. Stories that are important in and of themselves generally have statements rather than questions in the headline.
Invoking Betteridge's Law may well itself be an over-used trope, but if it is it's only because there's so very, very much call for it. News aggregators like Slashdot serve as concentrators, seeking out the most exciting stories. Ideally, the editors would serve as filters as well, recognizing exaggerated headlines and either ignoring them or putting them back into proper context. Instead, it's usually left to a poster to do that, generally after a lot of excited and/or outraged posting based on the headline. (Because the posters who just read the headline will always get there before people who bothered to RTFA.)
And you're going to demonstrate your independence by reiterating a weak pun that's well worn enough to have both a Wikipedia entry (which notes its "shrill and excessive use") and an XKCD already in place?
But it's worth noting that the converse is not true: not all unreasonable people make progress. Unreasonable people would ideally consider whether they're actually achieving something, or just being assholes.
Unfortunately, by definition that's something an unreasonable person cannot do. So the world ends up sorting through self-congratulatory dipsticks, hoping to find the smallish fraction who actually merit congratulations.