(Note that adjusting a wing by flexing it - slightly, over its full surface - has been around for a VERY long time. The Wright Brothers used it for yaw control, though they augmented (not replaced) it with a vertical rudder, starting with the glider that immediately preceded the "first powered flight" craft.)
All of which makes the article's breathless touting of this "innovation" pretty funny.
Two of the most basic moves in engineering are:
1) Take two functions that used to be separate and integrate them into a single component. This increases efficiency.
2) Take two functions that are performed by a single component and split them apart. This increases robustness.
Which move is a good idea at any time depends heavily on technology. Wing-warping (lift and control both done by the same component) was a poor fit for wood-and-fabric technology, so ailerons (lift and control done by separate components) was a good move. Metal frames and skins were not much different from wood and fabric in this regard, but now we are making aircraft mostly out of plastic (https://en.wikipedia.org/wiki/Boeing_787_Dreamliner) it may be time to reconsider the problem (which I guess has been done for some military aircraft already).
But it's not like this is a super-innovative work of genius. It's a pretty standard move that any good engineer is likely to consider when faced with a problem of efficiency (although exactly why integrated flaps are supposed to be such a huge improvement is not at all clear from TFA).
Rather than just admit that "when you hear hoofbeats, think of horses not zebras" (ie, the simplest explanation is usually the right one)
What makes horses simple and zebras complex?
Answer: nothing.
The issue is not simplicity, but prior probability. All else being equal, horses are more likely in most locales than zebras. When you hear hoofbeats, the plausibility of "There is a horse nearby" and "There is a zebra nearby" go up by the same factor. Since horses were already more likely, horses are still more likely.
Ockham's razor works, in the very few cases it does, as a consequence of Bayes' rule, and invoking some ill-defined notion of "simplicity" rather than prior plausibility is misleading.
In general, this is correct: you can prove a scientific theory false, but never prove it true.
Science is the discipline of publicly testing ideas by systematic observation, controlled experiment, and Bayesian inference.
Because science is at heart applied Bayesian reasoning it is not in the business of certainty of any kind: theories become more plausible or less plausible, and are never "true" or "false", which would imply that they are immune to any further evidence whatsoever. This state simply cannot be achieved within the Bayesian formalism.
The quest for certainty is science's equivalent of alchemy: alchemists weren't wrong because of their investigative techniques (which were often quite good) but because they were pursuing the wrong goal (transmutation of the elements). The proper goal of science is not certainty but knowledge, which is inherently uncertain. Philosophers don't understand this, and will no-doubt continue to promulgate the model of Poperian method for generations to come.
Massive generalization has been good to the sciences.
In physics, we have used invariance principles to expand our definitions to the most general possible. This was the argument behind General Relativity, for example: Einstein wanted equations of motion that would be invariant under any smooth second-order transformation whatsoever, and when he put that constraint, and only that constraint on, he found the most general form of the equations of motion were uniquely determined (up to a constant of integration, which is the Cosmological Constant).
Biologists have generally shied away from this kind of approach to their field, but there is an argument to be made that there is an equally general definition of "life" as "anything that participates in a process of evolution by imperfectly heritable traits that result in differential reproductive success". It need not be tied to any particular concrete mechanisms like DNA and RNA.
This idea may turn out to be silly (which is why I wrote a novel about it rather than a scientific paper: http://www.amazon.com/Darwins-...) but well into the 1800's there was no general view of "energy" that unified all the disparate forms, to the extent that the fact that light had energy that was in any way related to mechanical energy was not really appreciated. The kind of unified view of energy we have today would have seemed bizarrely speculative at that time, in the same way that the notion of a unified, generalized view of life is purely speculative today, but it turned out to be amazingly useful, so it's worth considering the possibility in biology today (anti-science people will likely attack it as a waste of money, using computer technology that would not exist without a similar "waste" on ridiculous fantasies like quantum theory and "obviously useless" research into the basic physics of semi-conductors in the past.)
Depends what you mean by nothing. by standard measures of "mass" or "energy" quantum fluctuations are pretty much nothing. In fact I'm pretty sure virtual particle pairs are *exactly* nothing if measured from a sufficient distance.
There's a joke attributed to Abraham Lincoln: Q: If you call a tail a leg, how many legs does a dog have? A: Four. Calling a tail a leg does not make it one.
Nothing in ordinary parlance (headlines, say) means an absolute absence, which is an empty concept, like the Philosopher's Stone or an honest politician. You don't get to decide for the sake a headline that it means something else. Only grasping little scumbag shills do that, people who are so fundamentally and thoroughly debased that they turn everything they touch--even language--into garbage.
"Pretty much nothing" is not "nothing". "In terms of mass and energy" is not a relevant restriction. The quantum vacuum is rich in properties. There is absolutely no basis to ignore those properties for the sake of a dishonest, misleading and confusing headline. It's like people who say "Before Europeans arrived North America had no people in it!" Which is true, for a certain value of "people". This is why precision in language matters, because there are people who actually say things like that to the considerable detriment of their fellow-humans.
"From a sufficient distance" would mean "infinity" if you want to talk about asymptotically vanishing properties of the vacuum, which would still leave all the other properties, so again: it isn't clear why anyone would dishonestly and stupidly restrict the discussion to one particular set of properties unless they wanted to dishonestly and stupidly made a false, dishonest and stupid claim that "the universe came from nothing!"
So other than being dishonest, stupid and wrong, there is nothing at all dishonest, stupid and wrong abut the claim "the universe came from nothing."
the algorith is old one, I remember it from Hugo Steinhaus's math book.
That's a really nice description. I wish this was better known. But...
The algorithm only works (in the sense of leaving the parties psychologically satisfied) if their preferences are transitive (that is, if they are not insane).
In reality, even sane people's preferences change in pseudo-non-transitive ways as possibilities become actualities. So when Caleb gets the car, Adam is going to wish he'd valued it more highly, and so on. Our inner monkey won't be happy until it gets more than everyone else.
There is also a considerable body of data showing that our ability to judge the value of stuff is very poor. Happiness research has been big on this, showing that most of what people think will make them happy is radically inferior to easily predictable things that will actually make them happy.
So while the algorithm is beautiful and general and ought to be used wherever appropriate, it is not going to satisfy people, and it will then fall out of use because no one is going to say, "I am broken" when they can say "The algorithm is broken" instead.
No one has any problem with investigating credible death threats. Random Internet death threats have just proven not to be credible. There is simply not enough resources to investigate them all. Simply a sad fact of life.
All kinds of people responding to this very story right here apparently have a problem with investigating credible death threats, which this very story is about. Some of those people are arbitrarily and without evidence claiming that death threats (which for some reason they designate as "random") over the Internet are not credible.
I'm not sure why anyone would consider a death threat against a controversial and apparently rather abrasive public figure "random" rather than, say, "motivated". If someone threatened me or you it would be "random", because we're just not very special or interesting (well, I'm not, anyway). But a public figure near the centre of the amazingly childish fit of anger known as "gamergate"? That's not random. It's motivated.
It's easy to dismiss credible, motivated threats when they are not against you. Stupid people lack the imagination to understand how unsettling it can be to get direct, specific threats against themselves that include details of where they live.
To declare an entire class of threats non-credible because of the medium used to deliver them is not reasonable. It's like the cops say, "Well, this note is written in crayon, so even though it says they're going to kill you it's not credible! Who ever took a note written in crayon seriously!" Ridiculous.
She uses a few instances of actual threats plus a lot of people calling her an idiot for saying moronic things to say she gets nonstop threats.
It isn't clear what your point is here.
She gets actual threats. You agree with that. So in response to actual threats she is offering a bounty to catch the people who have actually threatened her. You must also agree with that (if you aren't a sociopath) since a) actual threats are illegal and b) offering rewards to capture perpetrators of illegal behaviour is completely ordinary.
So beyond agreeing that she gets actual threats and is responding in a completely appropriate way, what's your point? That she's not a nice person? Who cares? Why is that remotely relevant to this story or this discussion?
"Not nice person gets actual threats and responds in a completely conventional and widely acceptable way". What is your problem with that? And why bring in some long list of irrelevancies that have nothing at all to do with it?
I type a comment here, and it goes into your brain.
But it doesn't go directly into my brain!
Where "directly" apparently means "via millions of dollars of highly specialized equipment", which is a use that only is only found in headlines on stories like this one.
"Humans can now transport themselves directly to the store in an automobile!"
Why is it that when we cut out the use of one organ--our feet in the case of automobiles--we all recognize that only a gibbering idiot would describe the resulting walking-free transportation process as "direct", but in the case of cutting out the use of the mouth almost everyone buys into this idiotic claim that its replacement by millions of dollars of gear is "direct"?
While I agree that something is odd with gravity, the certainty that many scientists seem to have that it must be an exotic particle or form we have not discovered seems misguided. It could be something exotic and new that doesn't fit with any previously discovered science... or not. Dark matter just fails Occam's Razor in my opinion.
I'm not sure why this was modded "Insightful" but it suggests that others share your questionable views, so I'll reply to them.
1) Scientists are not certain that dark matter is exotic particles, which is why scientists write papers like the one under discussion here. What seems misguided to me is people who are apparently ignorant of how science--which is the discipline of publicly testing ideas by systematic observation, controlled experiment, and/or Bayesian inference--works commenting negatively on how science works. It's a bit like Creationists critiquing their own bizarre views of "evolution" while ignoring the actual theory of evolution.
There has never been a time in the past several decades when any actual scientist has been even remotely certain about the nature of dark matter. Various ideas have been put forward, including ideas that modify gravity, and none of them have stood up to the routine tests applied to them. This has driven research toward exotic particles.
In particular: Big Bang Nucleosynthesis puts very tight constraints on the density of baryonic matter in the universe, and it's only about 5% of the amount needed to explain the large-scale cosmological observations that imply dark matter. So it isn't like scientists are just saying, "Yay! Evidence of new particles!" Rather we are saying, "Damn, there's a problem we can't solve with baryonic matter."
2) Occam's razor is stupid. You know, of course, that Occam himself used it to "prove" that nothing existed other than God, since to invoke other entities (matter, the Earth, shoes, cats...) to "explain" the phenomenology of experience would be to "multiply entities above necessity".
In the cases when it works or makes sense, Occam's razor is "Bayes' Rule for Dummies". The prior plausibility of a horse being around is higher than the prior plausibility of a zebra being around. Since both horses and zebras create hoofbeats with equal probability, hearing hoofbeats increases the plausibility of the propositions "There is a horse around" and "There is zebra around" by the same factor. Since horses were more plausible before, they are more plausible after.
Since P(hoofbeats|zebra) ~ P(hoofbeats|horse) and p(zebra) < p(horse) and P(hoofbeats) = P(hoofbeats), it is trivially true that p(zebra|hoofbeats) < p(horse|hoofbeats).
That's not exactly a ringing endorsement. It's more like "Ok, since we haven't found dark matter yet... this is way out there but hey, why not?"
The interesting bit of the paper is pointing out that observational limits excluding Standard Model-ish dark matter are incomplete. This is significant, as the new physics required to make stable "macros" of the kind discussed (nuclear-dense objects in the range of a few hundred grams to around the mass of the Earth, with a gap in the middle) is quite a bit less substantial than that required for physics beyond the Standard Model.
It it not-inconceivable that the strong force could have some weird metastable minimum for objects on this scale, and not being able to rule out such objects by observation is a problem, so we really should spend a bit of time closing those gaps.
I guess I shouldn't be surprised by all the non-sequitur hate this comment is getting from anonymous cowards. I don't generally reply to comments, but the ones here are so hateful and stupid it seems worth putting a word in.
No one asked anyone to do gay porn, for the illiterate amongst you. No one was asked to make out with anyone. You're going to have to address what I wrote rather than your fevered imaginations to get any traction, I'm afraid.
We frequently do films that cast actors as psychopaths, murderers, clowns, and worse, and no one ever objects, so any suggestion that playing a gay person is exceptionally offensive against the morals of the actor requires that it be more morally repugnant for them to play a gay person than a murderer. That is... odd.
Seriously, in one film there were half a dozen murders on screen. No one objected. Yet someone objected when given the option to play a gay person. If you don't see a problem with that, you're kind of screwed up.
We do not know exactly how high the cost will be, but we do know that it will be cheaper if we act now.
Absolutely. The difficulty is that "action" has to get past a fence of anti-science, anti-technology, anti-capitalist nutjobs who say on the one hand that a) we face a civilization-ending event and b) we must not use various well-known and ready-to-go solutions to the problem, but instead must embark on an unproven revolutionary program that "changes everything!"
Nuclear power, carbon taxes, and research in to carbon sequestration are the obvious immediate responses to climate change.
The first two are practical, proven and ready-to-go. The latter is a backup plan.
Instead we have left-wing idiots protesting oil pipelines, because that's where the donation dollars come from.
With regard to carbon taxes: we have to tax something to fund government. Even righties who just want to use government money to bomb brown people generally agree with that. We can tax income, or we can tax carbon emissions. Who but a raving anti-wealth socialist would want to tax something good and wonderful like income when we can tax some basically nasty like carbon emissions instead?
However, outside of the tech world, I've had to deal with plenty of people who are still disgusted by gays or get angry about the whole gay marriage thing
I work in tech in a very liberal Canadian city and have a bunch of gay friends, and sometimes get lulled into thinking the world is a big happy accepting place.
Then I step outside the downtown bubble, just by a few miles, and I'm stunned by what I sometimes encounter. I do a little writing for a group that makes short films, and we had a shoot where one of the actors didn't show up. He was part of a couple, and I suggested we recast the part using a woman who didn't have a part yet, so the couple would be gay but everything else would be the same. The film was about relationships and this couple was fighting about stuff. There might be a hug at the end, but nothing more overtly affectionate than that.
The young, professional woman I suggested this too looked at me with her eyes literally wide with horror and said, "I'm sorry, I can't do that. I'm really straight."
In that situation it wasn't my place to berate her for her bigotry, particularly as I didn't think until much later of the correct come-back: "You're really earthbound, too, but I bet you'd play an astronaut if I asked you to."
So yeah, while to so many of us this is a done deal, our gay friends and family still have to walk around every day wondering when they are going to encounter that kind of horrified rejection, and while at least they don't get beat up as often as they used to it still has to be pretty awful for them.
If anyone wants people like Tim Cook to stop making a big deal about being gay (and really, don't we all want that?) they should make sure to be accepting and matter-of-fact about the gay people all around us, whose much-talked-about "agenda" involves living happy, fulfilling lives.
A generation of rabid opposition to nuclear power is wrong, as is using climate change as a stick to beat global capitalism with rather than saying, "Hey, all we need is a carbon tax and we'll be done" (this is what the evidence in the Canadian province of British Columbia shows, anyway, but who cares about evidence when you're busy fighting global capitalism?)
This would be a revolutionary finding as it would be the first time that a superposition of states has been detected to measurably impact the interaction of a particle with its environment - in all previous QM experiments when a wavefunction collapsed and a single particle was detected, its position and velocity were consistent with the history of a single classical particle traveling along the path that ended in detection
I don't see that this experiment is any different from a photon reflecting between parallel partially-silvered mirrors. You see a range of arrival times at the detector, despite the wavefunction being "fragmented" by multiple reflections.
So this won't do anything to advance measurement theory. It is an interesting example because of the exotic circumstances. Your description is extremely good and quite plausible, although I haven't read the paper either.
Evaporation and emulsification; evaporation leaves behind the heavier components of oil, emulsification creates a seawater-oil mixture that will sink.
This is interesting, as there has been a huge fight in Canada about whether heavy oil sinks or floats (the answer seems to be: sinks, at least after some processing by sun/wind/flotsam/etc) but it has been presented to the public as if there was something special about that.
Whereas these results seem to indicate that a very substantial fraction of ordinary light crude sinks, so there is no particular additional danger posed by bitumen.
It's not yet settled whether there is some sort of discrimination or bias either keeping women out, or pushing them out.
Or, alternatively, men are being sold a bill of goods, as they always have been, about their prospects in a particular profession (soldiering comes to mind) and the poor weak-minded little dears that they are, they are buying into it, resulting in huge amounts of effort going to waste as boom turns to bust and men bear the personal cost of society selling them nonsense.
But of course, no one, anywhere, ever cares about men. After all, men have full and complete autonomy and are never in any way influenced by societal pressures or the social construction of masculinity. Men die earlier, commit suicide vastly more often, are the primary victims of violent crime, are killed on the job far more frequently... and it's all because of the bad choices they, as perfectly autonomous individuals make. What other reason could there possibly be?
This is a general problem with the way people infer origin dates from sparsely sampled distributions: http://www.tjradcliffe.com/?p=...
The earliest anatomically modern human fossils date from about 195,000 years ago, and people often say on this basis that anatomically modern humans appeared about 200,000 years ago, which is statistically illiterate at best.
Maybe people in the field know better, but I've seen an awful lot of claims like this and even in the semi-professional literature there seems to be a strong tendency to assume origin dates based on "date of earliest discovery plus a bit", which is just the wrong way to do it.
Well, I don't think that quite matches the scientific concept of "species".
There is no generally-agreed-upon "scientific concept of species". The "Biological Species Concept" is a well-know and highly contentious artifact. It is clearly useful, but how it is defined varies enormously from person to person and across sub-fields.
This variation doesn't matter much in practice, but it gives philosophers who for some unfathomable reason want there to be just one BSC fits. They seem unaware that concepts are tools used by knowing subjects to understand objective reality, so different subjects with different purposes will tweak the tool as appropriate, much the way a carpenter and a plumber are apt to use different types of hammer.
While you are correct that the airborne vector isn't significant need I remind you that Ebola is not a disease whereby the person infected with it gets a mild fever and minor headache and the cure is two aspirin tablets?
Sure, but that has zero bearing on the degree of concern people should have about the epidemic potential of Ebola in any country with a first-world health care system (Nigeria, say, or parts of the US outside Texas.)
The thing fearmongers like the GP are all about is the attempt to create a sense that Ebola could actually be spreading like the flu, which is so trivially false it isn't even worth mentioning. Yes, PPEs that include good respiratory protection should be part of the standard patient-handling protocol, and all due care should be taken to avoid droplet transmission, but Ebola's almost complete lack of aerosol transmission is and will remain a substantial barrier to the population risk the disease poses: http://www.tjradcliffe.com/?p=...
You don't want your tax dollars to go towards stem cell research? Fine, that's a reasonable request.
No, it's not. Democracy--any form of government, really, but especially democracy--requires that citizens accept the democratic will within broad constraints. These constraints are usually called "rights" or similar. In Canada we have the "Charter of Rights and Freedoms", In the US you've got the Bill of Rights. In the UK you've got "a marshal nobility and a stubborn commons, possessed of arms, tenacious of property", at least in theory.
Within those constraints, though: anything goes. I don't get to withhold my tax dollars from enterprises I don't support. Neither does anyone else. Do my tax dollars go to things I don't approve of? You're damned right they do, and at times those things cause the death of other human beings, including adult human beings (our current federal government in Canada is spending some of my tax dollars to fight harm-reduction as an approach to drug use, for example, and people are dying because of that.)
So it is not a reasonable request to withhold anyone's tax dollars from any publicly funded enterprise so long as due process has been followed in the funding. Don't like it? Get involved in politics and change it.
I just tried to exclude all BH postings (using the "excluded terms" thing in the options settings) and when I do I don't see any stories at all. Is his name somehow attached to every single story on/.?
Storms claims that there is no good theory to explain the excess heat measurements.
There is an excellent theory to explain the "excess heat" measurements: the people doing the research are some mixture of dishonest and incompetent. This theory also has the nice features that:
a) it is consistent with the spectacularly incompetent work we see whenever anyone attempts to carefully document an experiment, such as the one on the Rossi device we have seen recently
b) it is consistent with the litany of results that require well-established phenomenology to be turned off, for example the need to magically suppress neutrons and gamma rays that would otherwise be produced in any nuclear reaction or its aftermath, regardless of its origin.
After a quarter of a century with no reproducible results and no "positive" experiments that do not require the magical suppression of other laws of physics to account for the lack of radiation, no other theory is close to as plausible as this one.
Now I haven't seen anything convincing that indicates that cold fusion will work, but I also haven't heard of any significant investigation.
Cold fusion has been heavily investigated. There is one striking thing about all of the supposed "positive" results: they are physically impossible.
Suppose I said I had invented a car that ran on water, and that my claimed proof was that I had driven this car along the streets of a distant city. I give a talk on my results and show a map of the route.
A person in the audience interrupts and says, "Hey, I know that city! That's my home town! The route you've shown is impossible: you say you drove it between 4:30 and 5:30 PM on Tuesday June the 6th, which is in the middle of rush-hour, and you've shown yourself going the wrong way on half-a-dozen one-way streets! Why didn't you collide with anything?"
I reply: "This car runs on water! Weren't you listening? It doesn't collide with other cars, because it is propelled by water!"
You would be correct to suspect that you need not take my claims very seriously after that, and this kind of exchange is typical of cold fusion talks.
I saw Pons give a talk at Caltech, where one of my colleagues interrupted with the question, "Where are the neutrons? You say you don't see any radiation because all the energy comes out in high-energy alpha particles, but if you make alpha particles move with that energy through the palladium lattice you will get neutrons? Where are they?"
Pons answered: "New physics."
But alpha particles don't care what made them move, and more than a car cares what fuel it runs on. You can't just invoke "new physics" and say that the lack of neutrons or gamma rays doesn't matter, because you aren't really invoking new physics, you are throwing out old physics: you are saying that high energy alphas don't produce neutrons, even though that would require all of nuclear physics to be wrong.
So while I agree that new phenomena are often difficult to reproduce and we should be cautious about dismissing them on that basis, cold fusion, after twenty-five years of testing, has proven to be:
a) impossible to reproduce (there is no reliably reproducible experimental setup)
and
b) what experiments that have claimed positive results have always (to the best of my knowledge) required almost all of nuclear physics to be wrong to explain the absence of radiation.
I cannot think of any other phenomenon that eventually proved to exist that shares anything like this history of failure. Maybe Lister's work on sterile technique in surgery, which had a decade or two of rough handling? But even it was frequently reproducible, even if not universally so, and it didn't contradict any well-established, empirically founded, reasonably comprehensive theories of the time.
Slashdot Mirror
(Note that adjusting a wing by flexing it - slightly, over its full surface - has been around for a VERY long time. The Wright Brothers used it for yaw control, though they augmented (not replaced) it with a vertical rudder, starting with the glider that immediately preceded the "first powered flight" craft.)
All of which makes the article's breathless touting of this "innovation" pretty funny.
Two of the most basic moves in engineering are:
1) Take two functions that used to be separate and integrate them into a single component. This increases efficiency.
2) Take two functions that are performed by a single component and split them apart. This increases robustness.
Which move is a good idea at any time depends heavily on technology. Wing-warping (lift and control both done by the same component) was a poor fit for wood-and-fabric technology, so ailerons (lift and control done by separate components) was a good move. Metal frames and skins were not much different from wood and fabric in this regard, but now we are making aircraft mostly out of plastic (https://en.wikipedia.org/wiki/Boeing_787_Dreamliner) it may be time to reconsider the problem (which I guess has been done for some military aircraft already).
But it's not like this is a super-innovative work of genius. It's a pretty standard move that any good engineer is likely to consider when faced with a problem of efficiency (although exactly why integrated flaps are supposed to be such a huge improvement is not at all clear from TFA).
Rather than just admit that "when you hear hoofbeats, think of horses not zebras" (ie, the simplest explanation is usually the right one)
What makes horses simple and zebras complex?
Answer: nothing.
The issue is not simplicity, but prior probability. All else being equal, horses are more likely in most locales than zebras. When you hear hoofbeats, the plausibility of "There is a horse nearby" and "There is a zebra nearby" go up by the same factor. Since horses were already more likely, horses are still more likely.
Ockham's razor works, in the very few cases it does, as a consequence of Bayes' rule, and invoking some ill-defined notion of "simplicity" rather than prior plausibility is misleading.
In general, this is correct: you can prove a scientific theory false, but never prove it true.
Science is the discipline of publicly testing ideas by systematic observation, controlled experiment, and Bayesian inference.
Because science is at heart applied Bayesian reasoning it is not in the business of certainty of any kind: theories become more plausible or less plausible, and are never "true" or "false", which would imply that they are immune to any further evidence whatsoever. This state simply cannot be achieved within the Bayesian formalism.
The quest for certainty is science's equivalent of alchemy: alchemists weren't wrong because of their investigative techniques (which were often quite good) but because they were pursuing the wrong goal (transmutation of the elements). The proper goal of science is not certainty but knowledge, which is inherently uncertain. Philosophers don't understand this, and will no-doubt continue to promulgate the model of Poperian method for generations to come.
Massive generalization has been good to the sciences.
In physics, we have used invariance principles to expand our definitions to the most general possible. This was the argument behind General Relativity, for example: Einstein wanted equations of motion that would be invariant under any smooth second-order transformation whatsoever, and when he put that constraint, and only that constraint on, he found the most general form of the equations of motion were uniquely determined (up to a constant of integration, which is the Cosmological Constant).
Biologists have generally shied away from this kind of approach to their field, but there is an argument to be made that there is an equally general definition of "life" as "anything that participates in a process of evolution by imperfectly heritable traits that result in differential reproductive success". It need not be tied to any particular concrete mechanisms like DNA and RNA.
This idea may turn out to be silly (which is why I wrote a novel about it rather than a scientific paper: http://www.amazon.com/Darwins-...) but well into the 1800's there was no general view of "energy" that unified all the disparate forms, to the extent that the fact that light had energy that was in any way related to mechanical energy was not really appreciated. The kind of unified view of energy we have today would have seemed bizarrely speculative at that time, in the same way that the notion of a unified, generalized view of life is purely speculative today, but it turned out to be amazingly useful, so it's worth considering the possibility in biology today (anti-science people will likely attack it as a waste of money, using computer technology that would not exist without a similar "waste" on ridiculous fantasies like quantum theory and "obviously useless" research into the basic physics of semi-conductors in the past.)
Depends what you mean by nothing. by standard measures of "mass" or "energy" quantum fluctuations are pretty much nothing. In fact I'm pretty sure virtual particle pairs are *exactly* nothing if measured from a sufficient distance.
There's a joke attributed to Abraham Lincoln: Q: If you call a tail a leg, how many legs does a dog have? A: Four. Calling a tail a leg does not make it one.
Nothing in ordinary parlance (headlines, say) means an absolute absence, which is an empty concept, like the Philosopher's Stone or an honest politician. You don't get to decide for the sake a headline that it means something else. Only grasping little scumbag shills do that, people who are so fundamentally and thoroughly debased that they turn everything they touch--even language--into garbage.
"Pretty much nothing" is not "nothing". "In terms of mass and energy" is not a relevant restriction. The quantum vacuum is rich in properties. There is absolutely no basis to ignore those properties for the sake of a dishonest, misleading and confusing headline. It's like people who say "Before Europeans arrived North America had no people in it!" Which is true, for a certain value of "people". This is why precision in language matters, because there are people who actually say things like that to the considerable detriment of their fellow-humans.
"From a sufficient distance" would mean "infinity" if you want to talk about asymptotically vanishing properties of the vacuum, which would still leave all the other properties, so again: it isn't clear why anyone would dishonestly and stupidly restrict the discussion to one particular set of properties unless they wanted to dishonestly and stupidly made a false, dishonest and stupid claim that "the universe came from nothing!"
So other than being dishonest, stupid and wrong, there is nothing at all dishonest, stupid and wrong abut the claim "the universe came from nothing."
the algorith is old one, I remember it from Hugo Steinhaus's math book.
That's a really nice description. I wish this was better known. But...
The algorithm only works (in the sense of leaving the parties psychologically satisfied) if their preferences are transitive (that is, if they are not insane).
In reality, even sane people's preferences change in pseudo-non-transitive ways as possibilities become actualities. So when Caleb gets the car, Adam is going to wish he'd valued it more highly, and so on. Our inner monkey won't be happy until it gets more than everyone else.
There is also a considerable body of data showing that our ability to judge the value of stuff is very poor. Happiness research has been big on this, showing that most of what people think will make them happy is radically inferior to easily predictable things that will actually make them happy.
So while the algorithm is beautiful and general and ought to be used wherever appropriate, it is not going to satisfy people, and it will then fall out of use because no one is going to say, "I am broken" when they can say "The algorithm is broken" instead.
No one has any problem with investigating credible death threats. Random Internet death threats have just proven not to be credible. There is simply not enough resources to investigate them all. Simply a sad fact of life.
All kinds of people responding to this very story right here apparently have a problem with investigating credible death threats, which this very story is about. Some of those people are arbitrarily and without evidence claiming that death threats (which for some reason they designate as "random") over the Internet are not credible.
I'm not sure why anyone would consider a death threat against a controversial and apparently rather abrasive public figure "random" rather than, say, "motivated". If someone threatened me or you it would be "random", because we're just not very special or interesting (well, I'm not, anyway). But a public figure near the centre of the amazingly childish fit of anger known as "gamergate"? That's not random. It's motivated.
It's easy to dismiss credible, motivated threats when they are not against you. Stupid people lack the imagination to understand how unsettling it can be to get direct, specific threats against themselves that include details of where they live.
To declare an entire class of threats non-credible because of the medium used to deliver them is not reasonable. It's like the cops say, "Well, this note is written in crayon, so even though it says they're going to kill you it's not credible! Who ever took a note written in crayon seriously!" Ridiculous.
She uses a few instances of actual threats plus a lot of people calling her an idiot for saying moronic things to say she gets nonstop threats.
It isn't clear what your point is here.
She gets actual threats. You agree with that. So in response to actual threats she is offering a bounty to catch the people who have actually threatened her. You must also agree with that (if you aren't a sociopath) since a) actual threats are illegal and b) offering rewards to capture perpetrators of illegal behaviour is completely ordinary.
So beyond agreeing that she gets actual threats and is responding in a completely appropriate way, what's your point? That she's not a nice person? Who cares? Why is that remotely relevant to this story or this discussion?
"Not nice person gets actual threats and responds in a completely conventional and widely acceptable way". What is your problem with that? And why bring in some long list of irrelevancies that have nothing at all to do with it?
I type a comment here, and it goes into your brain.
But it doesn't go directly into my brain!
Where "directly" apparently means "via millions of dollars of highly specialized equipment", which is a use that only is only found in headlines on stories like this one.
"Humans can now transport themselves directly to the store in an automobile!"
Why is it that when we cut out the use of one organ--our feet in the case of automobiles--we all recognize that only a gibbering idiot would describe the resulting walking-free transportation process as "direct", but in the case of cutting out the use of the mouth almost everyone buys into this idiotic claim that its replacement by millions of dollars of gear is "direct"?
While I agree that something is odd with gravity, the certainty that many scientists seem to have that it must be an exotic particle or form we have not discovered seems misguided. It could be something exotic and new that doesn't fit with any previously discovered science... or not. Dark matter just fails Occam's Razor in my opinion.
I'm not sure why this was modded "Insightful" but it suggests that others share your questionable views, so I'll reply to them.
1) Scientists are not certain that dark matter is exotic particles, which is why scientists write papers like the one under discussion here. What seems misguided to me is people who are apparently ignorant of how science--which is the discipline of publicly testing ideas by systematic observation, controlled experiment, and/or Bayesian inference--works commenting negatively on how science works. It's a bit like Creationists critiquing their own bizarre views of "evolution" while ignoring the actual theory of evolution.
There has never been a time in the past several decades when any actual scientist has been even remotely certain about the nature of dark matter. Various ideas have been put forward, including ideas that modify gravity, and none of them have stood up to the routine tests applied to them. This has driven research toward exotic particles.
In particular: Big Bang Nucleosynthesis puts very tight constraints on the density of baryonic matter in the universe, and it's only about 5% of the amount needed to explain the large-scale cosmological observations that imply dark matter. So it isn't like scientists are just saying, "Yay! Evidence of new particles!" Rather we are saying, "Damn, there's a problem we can't solve with baryonic matter."
2) Occam's razor is stupid. You know, of course, that Occam himself used it to "prove" that nothing existed other than God, since to invoke other entities (matter, the Earth, shoes, cats...) to "explain" the phenomenology of experience would be to "multiply entities above necessity".
In the cases when it works or makes sense, Occam's razor is "Bayes' Rule for Dummies". The prior plausibility of a horse being around is higher than the prior plausibility of a zebra being around. Since both horses and zebras create hoofbeats with equal probability, hearing hoofbeats increases the plausibility of the propositions "There is a horse around" and "There is zebra around" by the same factor. Since horses were more plausible before, they are more plausible after.
That is:
p(zebra|hoofbeats) = P(hoofbeats|zebra)*p(zebra)/P(hoofbeats)
p(horse|hoofbeats) = P(hoofbeats|horse)*p(horse)/P(hoofbeats)
Since P(hoofbeats|zebra) ~ P(hoofbeats|horse) and p(zebra) < p(horse) and P(hoofbeats) = P(hoofbeats), it is trivially true that p(zebra|hoofbeats) < p(horse|hoofbeats).
No notions of "simplicity" are required.
So: your comment is quite badly mistaken.
That's not exactly a ringing endorsement. It's more like "Ok, since we haven't found dark matter yet... this is way out there but hey, why not?"
The interesting bit of the paper is pointing out that observational limits excluding Standard Model-ish dark matter are incomplete. This is significant, as the new physics required to make stable "macros" of the kind discussed (nuclear-dense objects in the range of a few hundred grams to around the mass of the Earth, with a gap in the middle) is quite a bit less substantial than that required for physics beyond the Standard Model.
It it not-inconceivable that the strong force could have some weird metastable minimum for objects on this scale, and not being able to rule out such objects by observation is a problem, so we really should spend a bit of time closing those gaps.
I guess I shouldn't be surprised by all the non-sequitur hate this comment is getting from anonymous cowards. I don't generally reply to comments, but the ones here are so hateful and stupid it seems worth putting a word in.
No one asked anyone to do gay porn, for the illiterate amongst you. No one was asked to make out with anyone. You're going to have to address what I wrote rather than your fevered imaginations to get any traction, I'm afraid.
We frequently do films that cast actors as psychopaths, murderers, clowns, and worse, and no one ever objects, so any suggestion that playing a gay person is exceptionally offensive against the morals of the actor requires that it be more morally repugnant for them to play a gay person than a murderer. That is... odd.
Seriously, in one film there were half a dozen murders on screen. No one objected. Yet someone objected when given the option to play a gay person. If you don't see a problem with that, you're kind of screwed up.
We do not know exactly how high the cost will be, but we do know that it will be cheaper if we act now.
Absolutely. The difficulty is that "action" has to get past a fence of anti-science, anti-technology, anti-capitalist nutjobs who say on the one hand that a) we face a civilization-ending event and b) we must not use various well-known and ready-to-go solutions to the problem, but instead must embark on an unproven revolutionary program that "changes everything!"
Nuclear power, carbon taxes, and research in to carbon sequestration are the obvious immediate responses to climate change.
The first two are practical, proven and ready-to-go. The latter is a backup plan.
Instead we have left-wing idiots protesting oil pipelines, because that's where the donation dollars come from.
With regard to carbon taxes: we have to tax something to fund government. Even righties who just want to use government money to bomb brown people generally agree with that. We can tax income, or we can tax carbon emissions. Who but a raving anti-wealth socialist would want to tax something good and wonderful like income when we can tax some basically nasty like carbon emissions instead?
However, outside of the tech world, I've had to deal with plenty of people who are still disgusted by gays or get angry about the whole gay marriage thing
I work in tech in a very liberal Canadian city and have a bunch of gay friends, and sometimes get lulled into thinking the world is a big happy accepting place.
Then I step outside the downtown bubble, just by a few miles, and I'm stunned by what I sometimes encounter. I do a little writing for a group that makes short films, and we had a shoot where one of the actors didn't show up. He was part of a couple, and I suggested we recast the part using a woman who didn't have a part yet, so the couple would be gay but everything else would be the same. The film was about relationships and this couple was fighting about stuff. There might be a hug at the end, but nothing more overtly affectionate than that.
The young, professional woman I suggested this too looked at me with her eyes literally wide with horror and said, "I'm sorry, I can't do that. I'm really straight."
In that situation it wasn't my place to berate her for her bigotry, particularly as I didn't think until much later of the correct come-back: "You're really earthbound, too, but I bet you'd play an astronaut if I asked you to."
So yeah, while to so many of us this is a done deal, our gay friends and family still have to walk around every day wondering when they are going to encounter that kind of horrified rejection, and while at least they don't get beat up as often as they used to it still has to be pretty awful for them.
If anyone wants people like Tim Cook to stop making a big deal about being gay (and really, don't we all want that?) they should make sure to be accepting and matter-of-fact about the gay people all around us, whose much-talked-about "agenda" involves living happy, fulfilling lives.
A generation of rabid opposition to nuclear power is wrong, as is using climate change as a stick to beat global capitalism with rather than saying, "Hey, all we need is a carbon tax and we'll be done" (this is what the evidence in the Canadian province of British Columbia shows, anyway, but who cares about evidence when you're busy fighting global capitalism?)
This would be a revolutionary finding as it would be the first time that a superposition of states has been detected to measurably impact the interaction of a particle with its environment - in all previous QM experiments when a wavefunction collapsed and a single particle was detected, its position and velocity were consistent with the history of a single classical particle traveling along the path that ended in detection
I don't see that this experiment is any different from a photon reflecting between parallel partially-silvered mirrors. You see a range of arrival times at the detector, despite the wavefunction being "fragmented" by multiple reflections.
So this won't do anything to advance measurement theory. It is an interesting example because of the exotic circumstances. Your description is extremely good and quite plausible, although I haven't read the paper either.
Evaporation and emulsification; evaporation leaves behind the heavier components of oil, emulsification creates a seawater-oil mixture that will sink.
This is interesting, as there has been a huge fight in Canada about whether heavy oil sinks or floats (the answer seems to be: sinks, at least after some processing by sun/wind/flotsam/etc) but it has been presented to the public as if there was something special about that.
Whereas these results seem to indicate that a very substantial fraction of ordinary light crude sinks, so there is no particular additional danger posed by bitumen.
It's not yet settled whether there is some sort of discrimination or bias either keeping women out, or pushing them out.
Or, alternatively, men are being sold a bill of goods, as they always have been, about their prospects in a particular profession (soldiering comes to mind) and the poor weak-minded little dears that they are, they are buying into it, resulting in huge amounts of effort going to waste as boom turns to bust and men bear the personal cost of society selling them nonsense.
But of course, no one, anywhere, ever cares about men. After all, men have full and complete autonomy and are never in any way influenced by societal pressures or the social construction of masculinity. Men die earlier, commit suicide vastly more often, are the primary victims of violent crime, are killed on the job far more frequently... and it's all because of the bad choices they, as perfectly autonomous individuals make. What other reason could there possibly be?
This is a general problem with the way people infer origin dates from sparsely sampled distributions: http://www.tjradcliffe.com/?p=...
The earliest anatomically modern human fossils date from about 195,000 years ago, and people often say on this basis that anatomically modern humans appeared about 200,000 years ago, which is statistically illiterate at best.
Maybe people in the field know better, but I've seen an awful lot of claims like this and even in the semi-professional literature there seems to be a strong tendency to assume origin dates based on "date of earliest discovery plus a bit", which is just the wrong way to do it.
Well, I don't think that quite matches the scientific concept of "species".
There is no generally-agreed-upon "scientific concept of species". The "Biological Species Concept" is a well-know and highly contentious artifact. It is clearly useful, but how it is defined varies enormously from person to person and across sub-fields.
This variation doesn't matter much in practice, but it gives philosophers who for some unfathomable reason want there to be just one BSC fits. They seem unaware that concepts are tools used by knowing subjects to understand objective reality, so different subjects with different purposes will tweak the tool as appropriate, much the way a carpenter and a plumber are apt to use different types of hammer.
While you are correct that the airborne vector isn't significant need I remind you that Ebola is not a disease whereby the person infected with it gets a mild fever and minor headache and the cure is two aspirin tablets?
Sure, but that has zero bearing on the degree of concern people should have about the epidemic potential of Ebola in any country with a first-world health care system (Nigeria, say, or parts of the US outside Texas.)
The thing fearmongers like the GP are all about is the attempt to create a sense that Ebola could actually be spreading like the flu, which is so trivially false it isn't even worth mentioning. Yes, PPEs that include good respiratory protection should be part of the standard patient-handling protocol, and all due care should be taken to avoid droplet transmission, but Ebola's almost complete lack of aerosol transmission is and will remain a substantial barrier to the population risk the disease poses: http://www.tjradcliffe.com/?p=...
You don't want your tax dollars to go towards stem cell research? Fine, that's a reasonable request.
No, it's not. Democracy--any form of government, really, but especially democracy--requires that citizens accept the democratic will within broad constraints. These constraints are usually called "rights" or similar. In Canada we have the "Charter of Rights and Freedoms", In the US you've got the Bill of Rights. In the UK you've got "a marshal nobility and a stubborn commons, possessed of arms, tenacious of property", at least in theory.
Within those constraints, though: anything goes. I don't get to withhold my tax dollars from enterprises I don't support. Neither does anyone else. Do my tax dollars go to things I don't approve of? You're damned right they do, and at times those things cause the death of other human beings, including adult human beings (our current federal government in Canada is spending some of my tax dollars to fight harm-reduction as an approach to drug use, for example, and people are dying because of that.)
So it is not a reasonable request to withhold anyone's tax dollars from any publicly funded enterprise so long as due process has been followed in the funding. Don't like it? Get involved in politics and change it.
I just tried to exclude all BH postings (using the "excluded terms" thing in the options settings) and when I do I don't see any stories at all. Is his name somehow attached to every single story on /.?
Storms claims that there is no good theory to explain the excess heat measurements.
There is an excellent theory to explain the "excess heat" measurements: the people doing the research are some mixture of dishonest and incompetent. This theory also has the nice features that:
a) it is consistent with the spectacularly incompetent work we see whenever anyone attempts to carefully document an experiment, such as the one on the Rossi device we have seen recently
b) it is consistent with the litany of results that require well-established phenomenology to be turned off, for example the need to magically suppress neutrons and gamma rays that would otherwise be produced in any nuclear reaction or its aftermath, regardless of its origin.
After a quarter of a century with no reproducible results and no "positive" experiments that do not require the magical suppression of other laws of physics to account for the lack of radiation, no other theory is close to as plausible as this one.
Now I haven't seen anything convincing that indicates that cold fusion will work, but I also haven't heard of any significant investigation.
Cold fusion has been heavily investigated. There is one striking thing about all of the supposed "positive" results: they are physically impossible.
Suppose I said I had invented a car that ran on water, and that my claimed proof was that I had driven this car along the streets of a distant city. I give a talk on my results and show a map of the route.
A person in the audience interrupts and says, "Hey, I know that city! That's my home town! The route you've shown is impossible: you say you drove it between 4:30 and 5:30 PM on Tuesday June the 6th, which is in the middle of rush-hour, and you've shown yourself going the wrong way on half-a-dozen one-way streets! Why didn't you collide with anything?"
I reply: "This car runs on water! Weren't you listening? It doesn't collide with other cars, because it is propelled by water!"
You would be correct to suspect that you need not take my claims very seriously after that, and this kind of exchange is typical of cold fusion talks.
I saw Pons give a talk at Caltech, where one of my colleagues interrupted with the question, "Where are the neutrons? You say you don't see any radiation because all the energy comes out in high-energy alpha particles, but if you make alpha particles move with that energy through the palladium lattice you will get neutrons? Where are they?"
Pons answered: "New physics."
But alpha particles don't care what made them move, and more than a car cares what fuel it runs on. You can't just invoke "new physics" and say that the lack of neutrons or gamma rays doesn't matter, because you aren't really invoking new physics, you are throwing out old physics: you are saying that high energy alphas don't produce neutrons, even though that would require all of nuclear physics to be wrong.
So while I agree that new phenomena are often difficult to reproduce and we should be cautious about dismissing them on that basis, cold fusion, after twenty-five years of testing, has proven to be:
a) impossible to reproduce (there is no reliably reproducible experimental setup)
and
b) what experiments that have claimed positive results have always (to the best of my knowledge) required almost all of nuclear physics to be wrong to explain the absence of radiation.
I cannot think of any other phenomenon that eventually proved to exist that shares anything like this history of failure. Maybe Lister's work on sterile technique in surgery, which had a decade or two of rough handling? But even it was frequently reproducible, even if not universally so, and it didn't contradict any well-established, empirically founded, reasonably comprehensive theories of the time.