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China Tops Europe In R&D Intensity

ananyo Re:Meaningless values are meaningless. (134 comments)

Proportion of GDP spent on research is not a 'meaningless' number. The EU spent a great deal of time trying to (unsuccessfully) urging its member states to push their total spending up to 3%. They've since realized that no single metric can adequately measure a nation's capacity to innovate in science - but this measure is still part of a basket of metrics that it's perfectly reasonable to use to examine a country's commitment to science.
To be clear - there's little evidence that spending a lot of money science will get you a Google or a Genentech, but on the other hand, a fair bit of evidence that spending nothing will make it extremely unlikely. ie science spending is necessary but not sufficient.

about 3 months ago
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Polynesians May Have Invented Binary Math

ananyo Polynesians DIDN'T invent binary (170 comments)

http://www.nature.com/news/polynesian-people-used-binary-numbers-600-years-ago-1.14380
>>Cognitive scientist Rafael Nuñez at the University of California, San Diego, points out that the idea of binary systems is actually older than Mangarevan culture. “It can be traced back to at least ancient China, around the 9th century bc”, he says, and it can be found in the I Ching, a millennia-old Chinese text that inspired Leibniz. Nuñez adds that “other ancient groups, such as the Maya, used sophisticated combinations of binary and decimal systems to keep track of time and astronomical phenomena. Thus, the cognitive advantages underlying the Mangarevan counting system may not be unique.”

about 4 months ago
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Wild cheetahs rely on agility and acceleration, not top speed, to hunt

ananyo Re:They don't rely on top speed? (2 comments)

The submission's fairly clear no? "a cheetah’s sheer speed is not its ONLYweapon when it comes to hunting. Its success as a predator ALSO hinges on its lightening reflexes and ability to accelerate faster than a Ferrari".
The story title says they rely on agility and acceleration and not on hitting their top speed during hunting.

about 10 months ago
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Genetic Switches Behind 'Love' Identified In Prairie Voles

ananyo Re:Bonobos (102 comments)

Actually, the parallel to bonobos is inaccurate-despite the genetic similarities, they're not the closest primate model to us in terms of our secual behaviour. There are plenty of reasons to strongly suspect that humans are somewhat monogamous - eg human males and females are around the same size - for various reasons, strongly polygamous species tend to have larger males, smaller females. Of-course humans are not strictly monogamous - few stick with just one partner for their whole lives - but then neither do many other 'monogamous' species.
Lots of articles about our propensity for monogamy vs polygamy
eg http://www.slate.com/articles/health_and_science/human_evolution/2012/10/are_humans_monogamous_or_polygamous_the_evolution_of_human_mating_strategies_.html
>> Like so many other animals, human beings aren't really that monogamous. Better to say, we're monogamish.

about 10 months ago
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Genetic Switches Behind 'Love' Identified In Prairie Voles

ananyo Re:Or the opposite (102 comments)

On what evidence? It seems pretty obvious that -some- sort of epigenetic changes happen in the human brain too on -some- occasions. I doubt the researchers are arguing that human pair-bonding happens in exactly the same way as in prairie voles - just that there are some parallels. In any case, the cool thing is that they've shown epigenetic changes behind pair-bonding for the first time. (There's plenty of evidence that epigenetic changes influence other forms of complex human behaviour (eg see http://www.nature.com/news/2010/100908/full/467146a.html). No reason I can see for sex/love to be different.)

about 10 months ago
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Higgs Data Could Spell Trouble For Leading Big Bang Theory

ananyo Re:Ambiguity in title (259 comments)

Yup you're right. He's saying the vanilla version of 'inflation' is in trouble. Other more exotic versions might be OK - but none of them are really favored by the community at the moment.

1 year,1 day
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Living cells turned into computers

ananyo Re:What? (2 comments)

Funny

about a year ago
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Researchers Opt To Limit Uses of Open-access Publications

ananyo Re:Conflating open access and open source (172 comments)

From wiki, the infallible source of all wisdom: "Open access (OA) is the practice of providing unrestricted access via the Internet to peer-reviewed scholarly journal article"

'unrestricted access' is exactly what it isn't some would argue, if your licence doesn't allow text mining, for example.

about a year ago
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Researchers Opt To Limit Uses of Open-access Publications

ananyo Re:Conflating open access and open source (172 comments)

Many, many advocates of open access publication say that without liberal licenses, it's not open access at all. so there is an important argument over definition here. For instance, data mining is going to be the next 'big thing' - if you need separate deals with publishers in order for researchers to text mine, that's going to risk scuppering the field before it's really gotten off the ground. Many are under the impression these sorts of issues are left behind if you publish in open access journals - but they are not.

about a year ago
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Did Land-Dwellers Emerge 65 Million Years Earlier Than Was Thought?

ananyo Re:Okay Slashdot! (41 comments)

hi - there's no conspiracy here. I have no special insight in what slashdot editors look for in a submission but I imagine that if they see a well written synopsis that helps. There's no way slashdot (nor any other aggregator site) could ever be ahead of the MSM (if you include Nature in that) on this - as research papers are sent to journalists IN ADVANCE of publication. This is supposedly to allow reporters time to put together an accurate story but also allows journals to control the news agenda a little. So this is why newspapers around the world publish the same science stories from the big journals at the same time.
I live in the UK - so I tend to post stuff to slashdot during my morning. If an embargo lifts at 7 or 10pm in the UK (typical journal embargo times), I'm not around to post it until the next day. Other people often do post the same story before I can as a result.
Lastly, it's no secret that I work for Nature - that's why a link to the news site and some smart googling of my user name reveals who I am. I've noticed the journal Science does the same (sciencehabit). There are good and bad things about that - news stories in Science and Nature are authoritative, in-depth and well balanced. They're far better sources of science news than newspaper coverage by and large, which is patchy and superficial by and large and often fails to address the big holes in the research. Because slashdot has editorial control, the editors get to decide which stories they take and which ones they decline.
I would add that means that slashdot hasn't suffered from the same problems as some other sites, which link to pretty awful stories or worse, journalism-free press releases that are essentially advertisements from researchers/universities.

about a year ago
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Sub-Ice Antarctic Lake Vida Abounds With Life

ananyo Re:As cold as 13C? (122 comments)

Apologies - typo in my submission.

about a year ago
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Brain Scans of Rappers and Jazz Musicians Shed Light On Creativity

ananyo Feel the hate (92 comments)

I've been posting stories to Slashdot for about a year now. I'm regularly on the most accepted submitter list and I don't spam the site with submissions so I guess I'm doing something right.
I've been pretty impressed by the comments on all the stories - like many in this community I've got a PhD (protein crystallography) and/or a physical sciences background (Undergrad in physics). Like many, I'm also liberal/atheist. Comments are humorous, witty and often insightful. The level of debate is high, and move the story on or question it in interesting ways.
But I'm hugely disappointed at many of the comments left on this piece - dismissing an entire genre of music? That's narrow-minded redneck stuff. You might not like much that you hear - but then any genre that includes Public Enemy, Michael Franti (sorry - I'm out of touch since the 80s/early 90s) deserves respect.
There's a great deal of rock I do not like - it's misogynistic/derivative crap - but that's OK - I listen to the stuff that I like.
Few would think it ok to dismiss rock music in the way I'm seeing rap/hiphop dismissed here. Any thoughts on why?

about a year ago
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Nearly All Particle Physics Research To Be Open Access

ananyo Re:Welcome to 1999. (27 comments)

This allows free access to peer reviewed literature for free. ArXiv does not.
Not sure I can be clearer than that...

about a year and a half ago
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First Mammals Observed Regenerating Tissue

ananyo Re:And by "first" you mean, "not first" (89 comments)

That's an interesting story (covered quite well on the BBC unusually http://news.bbc.co.uk/1/hi/sci/tech/4888080.stm) but my faith in /.'s editorial staff is intact. The article you link to are about mice with various genes missing - it's an engineered lab mouse mdoel. The mice in the story here regenerate naturally. MRL mice are a disease model - and carry a lupus like disease - ie autoimmune disease-bad news (I'm not sure whether that's because of the missing p21 gene but it's quite possible. Disentangling that from the regenerative abilities is going to be tough - and they haven't managed it yet by the looks of things).
The fact these mice do this naturally, with no other ill-effects, is much more important in terms of making an impact on human health.

about a year and a half ago
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Nearly All Particle Physics Research To Be Open Access

ananyo Re:Welcome to 1999. (27 comments)

You are incorrect about Nature policy on Arxiv:
http://www.nature.com/authors/policies/confidentiality.html
"Contributions being prepared for or submitted to a Nature journal can be posted on recognized preprint servers (such as ArXiv or Nature Precedings), and on collaborative websites such as wikis or the author's blog"

The problem with ArXIv is that papers have yet to be formally peer-reviewed. It's certainly true that physicists post there and you can find (nearly) all papers there in some form - but many papers posted there don't make it past peer review. So that's why this is important.
But you know all that as you RTFS:
"Particle physics is already a paragon of openness, with most papers posted on the preprint server arXiv. But peer-reviewed versions are still published in subscription journals, and publishers and research consortia at facilities such as the Large Hadron Collider (LHC) have previously had to strike piecemeal deals to free up a few hundred articles."

about a year and a half ago
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Nearly All Particle Physics Research To Be Open Access

ananyo Re:They don't have to give up profit (27 comments)

But keep in mind that subscription fee journals typically charge hundreds of dollars for color and extra pages (e.g. most IEEE Transactions journals charges $300 per page over 8).

Many journals do that though - not just subscription based journals.
eg
http://www.oxfordjournals.org/our_journals/cid/for_authors/charges.html
"Open Access charges are in addition to any page charges and color charges that might apply. "

about a year and a half ago
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Nearly All Particle Physics Research To Be Open Access

ananyo Re:All in all this is a good thing, but ... (27 comments)

It's true that all the organizations you anme have OA mandates BUT, crucially, none mandate that you make the research publicly accessible from the minute the paper is published. I believe the NIH policy is actually 12 MONTHS after publication - that is of limited use to scientists.
http://publicaccess.nih.gov/
So these agencies are actually pandering to publishers even more (in some respects) than this consortium is - libraries will continue to have to buy subscriptions so that their scientists can access the literature from day one (vital in biomed and probably most other fields too).
With the deal described in the source, the costs are transparent - so it's very likely that, when the contracts come up for negotiation in 3 years or so, there will be pressure on publishers to reduce profits...

about a year and a half ago
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Function of 80% of the Human Genome Charted

ananyo Re:What about introns? (112 comments)

Introns are parts of genes that are excised before the DNA message gets turned into a protein. So these papers don't have much to do with introns. However, as an aside, it's well known that some introns do have biological functions....
 

about a year and a half ago

Submissions

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Astronomers unveil the most Earth-like exoplanet yet

ananyo ananyo writes  |  yesterday

ananyo (2519492) writes "In a paper just published in Science, Elisa Quintada, an astronomer at NASA, and her colleagues, describe the detection of a particularly special exoplanet. Kepler 186f appears to be the closest relative to Earth yet discovered. Located about 500 light-years away, in the direction of the constellation Cygnus, Kepler-186f has a radius between 0.97 and 1.25 that of Earth. And it orbits its parent star firmly inside the "habitable zone", in which temperatures are just right for liquid water."
Link to Original Source
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Paper microscope magnifies objects 2100 times and costs less than $1

ananyo ananyo writes  |  3 days ago

ananyo (2519492) writes "If ever a technology were ripe for disruption, it is the microscope. Microscopes are expensive and need to be serviced and maintained. Unfortunately, one important use of them is in poor-world laboratories and clinics, for identifying pathogens, and such places often have small budgets and lack suitably trained technicians.
Now Manu Prakash, a bioengineer at Stanford University, has designed a microscope made almost entirely of paper, which is so cheap that the question of servicing it goes out of the window. Individual Foldscopes are printed on A4 sheets of paper (ideally polymer-coated for durability). A pattern of perforations on the sheet marks out the ’scope’s components, which are colour-coded in a way intended to assist the user in the task of assembly.
The Foldscope’s non-paper components, a poppy-seed-sized spherical lens made of borosilicate or corundum, a light-emitting diode (LED), a watch battery, a switch and some copper tape to complete the electrical circuit, are pressed into or bonded onto the paper. (The lenses are actually bits of abrasive grit intended to roll around in tumblers that smooth-off metal parts.) A high-resolution version of this costs less than a dollar, and offers a magnification of up to 2,100 times and a resolving power of less than a micron. A lower-spec version (up to 400x magnification) costs less than 60 cents."

Link to Original Source
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UN report reveals odds of being murdered country-by-country

ananyo ananyo writes  |  about a week ago

ananyo (2519492) writes "A new UN report (link to data) details comprehensive country-by-country murder rates. Safest is Singapore, with just one killing per 480,000 people in 2012. In the world’s most violent country, Honduras, a man has a 1 in 9 chance of being murdered during his lifetime. The Economist includes an intriguing 'print only interactive' (see the PDF) and has some tongue-in-cheek tips on how to avoid being slain:
>First, don’t live in the Americas or Africa, where murder rates (one in 6,100 and one in 8,000 respectively) are more than four times as high as the rest of the world.
Next, be a woman. Your chance of being murdered will be barely a quarter what it would be were you a man. In fact, steer clear of men altogether: nearly half of all female murder-victims are killed by their partner or another (usually male) family member. But note that the gender imbalance is less pronounced in the rich world, probably because there is less banditry, a mainly male pursuit. In Japan and South Korea slightly over half of all murder victims are female.
Then, sit back and grow older. From the age of 30 onwards, murder rates fall steadily in most places."

Link to Original Source
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Organ regenerated inside a living animal for the first time

ananyo ananyo writes  |  about two weeks ago

ananyo (2519492) writes "Scientists at Edinburgh University have successfully persuaded an organ to regenerate inside an animal. As they report in the journal Development, they have treated, in mice, an organ called the thymus, which is a part of the immune system that runs down in old age. Instead of adding stem cells they have stimulated their animals’ thymuses to make more of a protein called FOXN1. This is a transcription factor (a molecular switch that activates genes).
The scientists knew from earlier experiments that FOXN1 is important for the embryonic development of the thymus, and speculated that it might also rejuvenate the organ in older animals. They bred a special strain of mice whose FOXN1 production could be stimulated specifically in the thymus by tamoxifen, a drug more familiar as a treatment for breast cancer.
In one-year-olds, stimulating FOXN1 production in the thymus caused it to become 2.7 times bigger within a month. In two-year-olds the increase was 2.6 times. Moreover, when the researchers studied the enlarged thymuses microscopically, and compared them with those from untreated control animals of the same ages, they found that the organs’ internal structures had reverted to their youthful nature."

Link to Original Source
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1930s immigrants to US who Americanized their names got income boost

ananyo ananyo writes  |  about three weeks ago

ananyo (2519492) writes "Economists—most famously the Freakonomics duo, Steven Levitt and Stephen Dubner—have long worried that having the “wrong” name could set you back in the labour market. A number of studies show that having an “ethnic-sounding” name tends to disadvantage job applicants (though others suggest that names matter little).
Waves of migrants to America did not need economists to tell them that their name could be a disadvantage. Many changed their names to fit in. Almost a third of naturalising immigrants abandoned their first names by 1930 and acquired popular American names such as William, John or Charles. What was the impact? The authors draw on a sample of 3,400 male migrants who naturalised in New York in 1930.
The authors found that changing from a purely foreign name to a very common American name was associated with a 14% hike in earnings."

Link to Original Source
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Homeopathic remedies recalled for containing real medicine

ananyo ananyo writes  |  about three weeks ago

ananyo (2519492) writes "The US Food and Drug Administration (FDA) has recalled homeopathic remedies made by a company called Terra-Medica because they may contain actual medicine — possibly penicillin or derivatives of the antibiotic."
Link to Original Source
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How to prevent a plane from vanishing again

ananyo ananyo writes  |  about three weeks ago

ananyo (2519492) writes "In an age of big data—when our cellphones track our location and American spooks know what we ate for breakfast—it seems bizarre that a huge airliner with 239 people on board could vanish with barely a trace.The incident reveals numerous security lapses that are relatively easy to fix—and must be, to maintain public confidence in air travel.
The first is the continual tracking of commercial airliners. Prior to MH370’s disappearance, most people would have presumed that aeroplanes are in constant communication with ground stations for security reasons if not navigational ones. But there is no requirement that they maintain continuous contact. The aviation industry plans to upgrade its radar to a GPS-based system that would accomplish this, but the process has faced delays. It should be implemented immediately.
Second, MH370 “went dark” about 40 minutes after takeoff because two communications systems were mysteriously deactivated: the secondary radar (which identifies the aircraft, among other data, to radar screens) and ACARS, a system for sending status updates and messages.
There are good reasons why pilots should be able to disable equipment on board, the threat of fires being one of them. But in such cases, the aeroplane should automatically send out an alert that the system is being shut off, so that authorities are immediately aware of this, and know to track the aircraft with conventional radar (where it appears as a blip on a screen without the identifying information)."

Link to Original Source
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New Stanford institute to target bad science

ananyo ananyo writes  |  about 1 month ago

ananyo (2519492) writes "John Ioannidis, the epidemiologist who published an infamous paper entitled 'Why most published research findings are false', has co-founded an institute dedicated to combating sloppy medical studies. The new institute is to focus on irreproducibility, waste in science and publication bias. The institute, called the Meta-Research Innovation Centre or METRICS, will, the Economist reports, 'create a “journal watch” to monitor scientific publishers’ work and to shame laggards into better behaviour. And they will spread the message to policymakers, governments and other interested parties, in an effort to stop them making decisions on the basis of flaky studies. All this in the name of the centre’s nerdishly valiant mission statement: “Identifying and minimising persistent threats to medical-research quality.”'"
Link to Original Source
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Why P-values cannot tell you if a hypothesis is correct

ananyo ananyo writes  |  about 2 months ago

ananyo (2519492) writes "P values, the 'gold standard' of statistical validity, are not as reliable as many scientists assume. Critically, they cannot tell you the odds that a hypothesis is correct. A feature in Nature looks at why, if a result looks too good to be true, it probably is, despite an impressive-seeming P value."
Link to Original Source
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Graphene conducts electricity ten times better than expected

ananyo ananyo writes  |  about 2 months ago

ananyo (2519492) writes "Physicists have produced nanoribbons of graphene — the single-atom-thick carbon — that conduct electrons better than theory predicted even for the most idealized form of the material. The finding could help graphene realize its promise in high-end electronics, where researchers have long hoped it could outperform traditional materials such as silicon.
In graphene, electrons can move faster than in any other material at room temperature. But techniques that cut sheets of graphene into the narrow ribbons needed to form wires of a nano-scale circuit leave ragged edges, which disrupt the electron flow. Now a team led by physicist Walt de Heer at the Georgia Institute of Technology in Atlanta has made ribbons that conduct electric charges for more than 10 micrometres without meeting resistance — 1,000 times farther than in typical graphene nanoribbons. The ribbons made by de Heer's team in fact conduct electrons ten times better than standard theories of electron transport they should, say the authors."

Link to Original Source
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India to build world's largest solar plant

ananyo ananyo writes  |  about 2 months ago

ananyo (2519492) writes "India has pledged to build the world’s most powerful solar plant. With a nominal capacity of 4,000 megawatts, comparable to that of four full-size nuclear reactors, the ‘ultra mega' project will be more than ten times larger than any other solar project built so far, and it will spread over 77 square kilometres of land — greater than the island of Manhattan.
Six state-owned companies have formed a joint venture to execute the project, which they say can be completed in seven years at a projected cost of US$4.4 billion. The proposed location is near Sambhar Salt Lake in the northern state of Rajasthan."

Link to Original Source
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Scientists reading fewer papers for first time in 35 years

ananyo ananyo writes  |  about 2 months ago

ananyo (2519492) writes "A 35-year trend of researchers reading ever more scholarly papers seems to have halted. In 2012, US scientists and social scientists estimated that they read, on average, 22 scholarly articles per month (or 264 per year), fewer than the 27 that they reported in an identical survey last conducted in 2005. It is the first time since the reading-habit questionnaire began in 1977 that manuscript consumption has dropped."
Link to Original Source
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Elsevier opens its papers to text-mining

ananyo ananyo writes  |  about 2 months ago

ananyo (2519492) writes "Publishing giant Elsevier says that it has now made it easy for scientists to extract facts and data computationally from its more than 11 million online research papers. Other publishers are likely to follow suit this year, lowering barriers to the computer-based research technique. But some scientists object that even as publishers roll out improved technical infrastructure and allow greater access, they are exerting tight legal controls over the way text-mining is done.
Under the arrangements, announced on 26 January at the American Library Association conference in Las Vegas, Nevada, researchers at academic institutions can use Elsevier’s online interface (API) to batch-download documents in computer-readable XML format. Elsevier has chosen to provisionally limit researchers to 10,000 articles per week. These can be freely mined — so long as the researchers, or their institutions, sign a legal agreement. The deal includes conditions: for instance, that researchers may publish the products of their text-mining work only under a licence that restricts use to non-commercial purposes, can include only snippets (of up to 200 characters) of the original text, and must include links to original content."

Link to Original Source
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Acid bath offers easy path to stem cells

ananyo ananyo writes  |  about 3 months ago

ananyo (2519492) writes "In 2006, Japanese researchers reported a technique for creating cells that have the embryonic ability to turn into almost any cell type in the mammalian body — the now-famous induced pluripotent stem (iPS) cells. In papers published this week in Nature, another Japanese team says that it has come up with a surprisingly simple method — exposure to stress, including a low pH — that can make cells that are even more malleable than iPS cells, and do it faster and more efficiently.
The work so far has focused on mouse white blood cells but the group are now trying to make the method work with cells adult humans. If they're succesful, that would dramatically speed up the process of creating stem cells for potential clinical applications."

Link to Original Source
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Stephen Hawking claims "there are no black holes"

ananyo ananyo writes  |  about 3 months ago

ananyo (2519492) writes "Stephen Hawking has proposed a new solution to the black-hole firewall paradox, which has been vexing physicists for almost two years, after its discovery by theoretical physicists Joe Polchinski at the Kavli Institute for Theoretical Physics in Santa Barbara, California, and colleagues. The paradox troubles physicists because if the firewall scenario is correct, Einstein’s general theory of relativity is flouted. But the classical theory black hole cannot be reconciled to the quantum mechanical prediction that energy and information can escape from a black hole.
Now Hawking has proposed a tantalizingly simple solution to the paradox which allows both quantum mechanics and general relativity to remain intact--black holes simply do not have an event horizon to catch fire. The key to his claim is that quantum effects around the black hole cause spacetime to fluctuate too wildly for a sharp boundary surface to exist. As Hawking writes in his paper, "The absence of event horizons mean that there are no black holes — in the sense of regimes from which light can't escape to infinity.""

Link to Original Source
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Why 'irrational' choices can be rational

ananyo ananyo writes  |  about 3 months ago

ananyo (2519492) writes "Organisms, including humans, are often assumed to be hard-wired by evolution to try to make optimal decisions, to the best of their knowledge. Ranking choices consistently — for example, in selecting food sources — would seem to be one aspect of such rationality. If A is preferred over B, and B over C, then surely A should be selected when the options are just A and C? This seemingly logical ordering of preferences is called transitivity.
Furthermore, if A is preferred when both B and C are available, then A should ‘rationally’ remain the first choice when only A and B are at hand — a principle called the independence of irrelevant alternatives (IIA).
But sometimes animals do not display such logic. For example, honeybees (Apis mellifera) and gray jays (Perisoreus canadensis) have been seen to violate IIA, and so have hummingbirds (Selasphorus rufus).
Researchers have now used a theoretical model to show that, in fact, violations of transitivity can sometimes be the best choice for the given situation, and therefore rational. The key is that the various choices might appear or disappear in the future. Then the decision becomes more complicated than a simple, fixed ranking of preferences. So while these choices look irrational, they aren’t necessarily."

Link to Original Source
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Physicists explain 'gravity-defying' chain trick

ananyo ananyo writes  |  about 3 months ago

ananyo (2519492) writes "Leaping up out of a jar in an arc before falling to the floor, the fountain-like motion of a chain of beads has puzzled millions around the world with its apparently gravity-defying behaviour. Now physicists think they have an explanation.
British science presenter Steve Mould, who made the experiment famous, explained the phenomenon as simply one of inertia: the falling chain has downward momentum, causing an upward momentum in beads leaving the pot. This, in turn, makes them leap before gravity can slowly reverse their momentum.
Mould’s explanation was clever, but wrong, says physicist John Biggins of the University of Cambridge, UK. The only way to account for the rise is for the chain to receive a 'kick' from the pot from which it is being pulled. This challenges not only the explanation given by Mould, but the conventional mathematics of chains, Biggins says."

Link to Original Source
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Ampere could be redefined after experiments track single electrons crossing chip

ananyo ananyo writes  |  about 3 months ago

ananyo (2519492) writes "Physicists have tracked electrons crossing a semiconductor chip one at a time — an experiment that should at last enable a rational definition of the ampere, the unit of electrical current.
At present, an ampere is defined as the amount of charge flowing per second through two infinitely long wires one metre apart, such that the wires attract each other with a force of 2×107 newtons per metre of length. That definition, adopted in 1948 and based on a thought experiment that can at best be approximated in the laboratory, is clumsy — almost as much of an embarrassment as the definition of the kilogram, which relies on the fluctuating mass of a 125-year-old platinum-and-iridium cylinder stored at the International Bureau of Weights and Measures in Paris.
The new approach, described in a paper posted onto the arXiv server on 19 December, would redefine the amp on the basis of e, a physical constant representing the charge of an electron."

Link to Original Source
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First recorded observation of freshwater fish preying on birds in flight

ananyo ananyo writes  |  about 3 months ago

ananyo (2519492) writes "The waters of the African lake seem calm and peaceful. A few migrant swallows flit near the surface. Suddenly, leaping from the water, a fish grabs one of the famously speedy birds straight out of the air.
“The whole action of jumping and catching the swallow in flight happens so incredibly quickly that after we first saw it, it took all of us a while to really fully comprehend what we had just seen,” says Nico Smit, director of the Unit for Environmental Sciences and Management at North-West University in Potchefstroom, South Africa.
After the images did sink in, he adds, “the first reaction was one of pure joy, because we realized that we were spectators to something really incredible and unique”.
  Rumours of such behaviour by the African tigerfish (Hydrocynus vittatus), which has been reported as reaching one metre in length, have circulated since the 1940s. But this is the first confirmed record of a freshwater fish preying on birds in flight, the team reports in the Journal of Fish Biology (PDF)."

Link to Original Source
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Swarms of small satellites set to deliver close to real-time imagery of Earth

ananyo ananyo writes  |  about 3 months ago

ananyo (2519492) writes "A swarm of small satellites set to deliver close to real-time imagery of swathes of the planet is launching today. San Francisco-based Planet Labs, founded in 2010 by three former NASA scientists, is scheduled to launch 28 of its ‘Doves’ on 9 January. Each toaster-sized device weighs about 5 kilograms and can take images at a resolution of 3–5 metres.
Meanwhile Skybox Imaging plans to launch a swarm of 24 satellites, each weighing about 100 kilograms, which will take images of 1 metre resolution or better. Skybox launched its first satellite on 21 November (and captured the first HD video of the world from space) and plans to launch another this year, followed by the remainder between 2015 and 2017. In a first — at least for civilian satellites — Skybox’s devices will also stream short segments of near-live high-resolution video footage of the planet. So, too, will UrtheCast, a start-up based in Vancouver, Canada, whose cameras will hitch a ride on the International Space Station.
Because the swarms are still to be launched, scientists have yet to fully assess the quality of the imagery. But the satellites’ spatial resolutions of 1–5 metres are much higher than those of most scientific satellites. Landsat, NASA’s Earth-observation workhorse, for example, has a resolution of 15–100 metres depending on the spectral frequency, with 30 metres in the visible-light range."

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