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Huzzah! Long unavailable (or at least not widely available), Errol Morris’ documentary film on Stephen Hawking and his work, A Brief History of Time, is now available for rent or purchase on iTunes. Or if you can wait a little bit, there’s a Criterion Blu-ray edition coming out in mid-March. Bonus: score by Philip Glass!
And if you want a sense of how weird, and how fraught, the relationship between science, politics, and commerce is in our modern world, then there’s really no better place to go.
In The Daily Beast Michael Schulson provides a alternate view on Whole Foods: America’s Temple of Pseudoscience. (The first time I read this, I nearly spit out my probiotic-infused kombucha, kale, quinoa, coconut water shake.)
Related to my post on the frequency of humanity is this post on XKCD on the various frequencies of events, from human births to dog bites to stolen bicycles.
There are too many camels in the Bible. Evidence suggests they were domesticated in Israel centuries after the events in Genesis took place.
Camels probably had little or no role in the lives of such early Jewish patriarchs as Abraham, Jacob and Joseph, who lived in the first half of the second millennium B.C., and yet stories about them mention these domesticated pack animals more than 20 times. Genesis 24, for example, tells of Abraham’s servant going by camel on a mission to find a wife for Isaac.
These anachronisms are telling evidence that the Bible was written or edited long after the events it narrates and is not always reliable as verifiable history. These camel stories “do not encapsulate memories from the second millennium,” said Noam Mizrahi, an Israeli biblical scholar, “but should be viewed as back-projections from a much later period.”
Dr. Mizrahi likened the practice to a historical account of medieval events that veers off to a description of “how people in the Middle Ages used semitrailers in order to transport goods from one European kingdom to another.”
Update: Added “in Israel” to clarify the camel domestication timeline…they were domesticated much earlier in the Arabian Peninsula.
Archaeologists have established that camels were probably domesticated in the Arabian Peninsula for use as pack animals sometime towards the end of the 2nd millennium BCE. In the southern Levant, where Israel is located, the oldest known domesticated camel bones are from the Aravah Valley, which runs along the Israeli-Jordanian border from the Dead Sea to the Red Sea and was an ancient center of copper production. At a 2009 dig, Dr. Ben-Yosef dated an Aravah Valley copper smelting camp where the domesticated camel bones were found to the 11th to 9th century BCE.
(via @arbesman)
About 250 million years ago, Earth suffered its fifth (and worst) mass extinction event. Nearly seventy percent of land species disappeared. And they got off easy compared to marine species. Are we headed for another mass extinction on Earth? I’m not ready to break that news. But something unusual is definitely going on and extinction rates seem to be speeding up. Here’s an interesting chat with Elizabeth Kolbert, author of The Sixth Extinction.
The worst mass extinction of all time came about 250 million years ago [the Permian-Triassic extinction event]. There’s a pretty good consensus there that this was caused by a huge volcanic event that went on for a long time and released a lot of carbon-dioxide into the atmosphere. That is pretty ominous considering that we are releasing a lot of CO2 into the atmosphere and people increasingly are drawing parallels between the two events.
What would happen if a tiny black hole the size of a marble were placed at the center of the Earth? Rest assured, the Earth won’t completely be swallowed up by the black hole but that’s really the only good news to offer.
First of all, not all of the Earth would simply be sucked into the black hole. When the matter near the black hole begins to fall into the black hole, it will be compressed to a very high density that will cause it to be heated to very high temperatures. These high temperatures will cause gamma rays, X-rays, and other radiation to heat up the other matter falling in to the black hole. The net effect will be that there will be a strong outward pressure on the outer layers of the Earth that will first slow down their fall and will eventually ionize and push the outer layers away from the black hole. So some inner portion of the core will fall into the black hole, but the outer layers, including the crust and all of us, would be vaporized to a high temperature plasma and blown into space.
This would be a gigantic explosion — a significant fraction of the rest of the mass of the Earth matter that actually fell into the black hole will be converted into energy.
FYI, that marble-sized black hole would have about the same mass as the Earth. Not that they exist, mind you. Maybe, maybe not. Blackish holes? Dark grey holes? Anyway, really heavy.
This is nutty…by chance, a group of archaeologists found what are believed to be the oldest known human footprints outside of Africa on a beach in England. The footprints are an estimated 800,000 years old and are now completely gone. The tide that uncovered them washed them away in less than a month.
The footprints have been described as “one of the most important discoveries, if not the most important discovery that has been made on [Britain’s] shores,” by Dr Nick Ashton of the British Museum.
“It will rewrite our understanding of the early human occupation of Britain and indeed of Europe,” he told BBC News.
The markings were first indentified in May last year during a low tide. Rough seas had eroded the sandy beach to reveal a series of elongated hollows.
The other day, Bill Nye debated Ken Ham about evolution and creationism. At the event, Matt Stopera asked self-identifying creationists to write question/notes to those who “believe” in evolution. Here’s one:
Phil Plait of Bad Astronomy responded to each of the 22 notes/questions from the creationists. Here’s his answer to the comment above:
I agree; it is amazing! I’ve written about this many times. But we know that complexity can arise naturally through the laws of physics. It doesn’t take very complex rules to create huge diversity. Look at poker; a simple set of rules creates a game that has so many combinations it’s essentially infinite to human experience. We can figure out the rules of nature by studying the way processes follow them, and deduce what’s going on behind the scenes. And whenever we do, we see science.
This makes me think of Richard Feynman’s ode to the scientific beauty of a flower:
I have a friend who’s an artist and has sometimes taken a view which I don’t agree with very well. He’ll hold up a flower and say “look how beautiful it is,” and I’ll agree. Then he says “I as an artist can see how beautiful this is but you as a scientist take this all apart and it becomes a dull thing,” and I think that he’s kind of nutty. First of all, the beauty that he sees is available to other people and to me too, I believe. Although I may not be quite as refined aesthetically as he is … I can appreciate the beauty of a flower. At the same time, I see much more about the flower than he sees. I could imagine the cells in there, the complicated actions inside, which also have a beauty. I mean it’s not just beauty at this dimension, at one centimeter; there’s also beauty at smaller dimensions, the inner structure, also the processes. The fact that the colors in the flower evolved in order to attract insects to pollinate it is interesting; it means that insects can see the color. It adds a question: does this aesthetic sense also exist in the lower forms? Why is it aesthetic? All kinds of interesting questions which the science knowledge only adds to the excitement, the mystery and the awe of a flower. It only adds. I don’t understand how it subtracts.
Every day on Earth, an estimated 371,124 people are born and 154,995 people die. When you ask Wolfram Alpha about these rates, the scientifically inclined site returns a curious corresponding quantity: the frequency in hertz (aka the number of cycles/second in a periodic occurrence).
Measurement in hertz is an unusual way to think about living and dying; hertz are typically reserved for things like human-audible sound frequencies (20 to 16,000 Hz), how fast your laptop’s CPU runs (1 to 4 Ghz), or the frequency of the power running into your house (50 to 60 Hz). But if you subtract the death rate from the birth rate, you get a net rate of 216,129 new people a day, or about 2.5 Hz. That’s the frequency of humanity. While that’s a lot slower than your computer, it’s in the same frequency ballpark as a human’s resting heart rate (1.3 Hz), steps taken while walking briskly (1.8 Hz), or moderately energetic dance music (2.25 Hz).
Note: Illustration by Chris Piascik…check out his shop, where you’ll find prints, tshirts, iPhone cases, etc.
In 1976, legendary cosmologist and astronomer Carl Sagan tried to recruit a 17-year-old Neil deGrasse Tyson to Cornell University. In April of that year, Tyson wrote Sagan a letter informing him of his intention to enroll at Harvard instead:
The Viking Missions referred to in the letter were the two probes sent to Mars in the mid-1970s.
Tyson occupies a role in today’s society similar to Sagan’s in the 1980s as an unofficial public spokesman of the wonderous world of science. Tyson is even hosting an updated version of Sagan’s seminal Cosmos series for Fox, which debuts on March 9th. Here’s a trailer:
Letter courtesy of The Seth Macfarlane Collection of the Carl Sagan and Ann Druyan Archive at the Library of Congress, which is chock full of great Sagan stuff. And yeah, that’s Seth Macfarlane, creator of Family Guy and much-maligned host of the Oscars. Macfarlane was a big fan of the original Cosmos series and was instrumental in getting the new series made. (via @john_overholt)
A geothermal engineering project in Iceland drilled 1.3 miles into the Earth and unexpectedly hit a pocket of magma. Instead of capping the hole, as was done in a similar instance previously, they decided to see if they could harness the energy of the magma.
“Drilling into magma is a very rare occurrence, and this is only the second known instance anywhere in the world,” Elders said. The IDDP and Iceland’s National Power Company, which operates the Krafla geothermal power plant nearby, decided to make a substantial investment to investigate the hole further.
This meant cementing a steel casing into the well, leaving a perforated section at the bottom closest to the magma. Heat was allowed to slowly build in the borehole, and eventually superheated steam flowed up through the well for the next two years.
Elders said that the success of the drilling was “amazing, to say the least”, adding: “This could lead to a revolution in the energy efficiency of high-temperature geothermal projects in the future.”
The well funnelled superheated, high-pressure steam for months at temperatures of over 450°C — a world record. In comparison, geothermal resources in the UK rarely reach higher than around 60-80°C.
In a short video from The Atlantic, science writer Philip Ball explains why Isaac Newton picked ROYGBIV (red, orange, yellow, green, blue, indigo, and violet) for the colors of the spectrum and not 3 or 6 or even 16 other possible colors.
Newton was the first to demonstrate through his famous prism experiments that color is intrinsic to light. As part of those experiments, he also divvied up the spectrum in his own idiosyncratic way, giving us ROYGBIV. Why indigo? Why violet? We don’t really know why Newton decided there were two distinct types of purple, but we do know he thought there should be seven fundamental colors.
Ball is the author of Bright Earth: Art and the Invention of Color, which looks pretty interesting. His mention in the video of the changing perception of color throughout history reminds me of my favorite segment of Radiolab, which covers that very topic.
In a thread about the newly visible supernova in the M82 galaxy, MetaFilter user Ivan Fyodorovich offered up this plain-English explanation of what happens when a star dies and goes supernova. It’s a great read.
It will take it just 6 months to burn up its oxygen. Again, when there’s not enough oxygen being fused to generate energy to balance the pressure of gravitational contraction, the star begins to shrink, almost doubling the temperature, tripling the density, and causing the silicon (which was produced by the oxygen fusion) to begin fusing, in its own complicated sequence involving the alpha process, with the end result of nickel-56 (which radioactively decays into cobalt-56 and iron-56). This, as before, balances against the gravitational pressure and returns the star to equilibrium.
And now it will take merely 1 day to burn up its silicon. Finally, when there’s not enough silicon being fused to generate energy to balance the pressure of gravitational contraction, the star begins to shrink.
This time, however, the core of the star is mostly nickel and iron, and they cannot ordinarily be fused into heavier elements, so as the star shrinks and the temperature and density increase, there is no nuclear fusion ignition of the nickel and iron to counteract the contraction. Here the limit of pressure and density is the electron degeneracy pressure, which is the resistance of electrons being forced to occupy the same energy states, which they can’t.
(via @mathowie)
In an “only Nixon can go to China” moment in physics, Stephen Hawking now says “there are no black holes”.
Most physicists foolhardy enough to write a paper claiming that “there are no black holes” — at least not in the sense we usually imagine — would probably be dismissed as cranks. But when the call to redefine these cosmic crunchers comes from Stephen Hawking, it’s worth taking notice. In a paper posted online, the physicist, based at the University of Cambridge, UK, and one of the creators of modern black-hole theory, does away with the notion of an event horizon, the invisible boundary thought to shroud every black hole, beyond which nothing, not even light, can escape.
In its stead, Hawking’s radical proposal is a much more benign “apparent horizon”, which only temporarily holds matter and energy prisoner before eventually releasing them, albeit in a more garbled form.
A supernova erupted recently1 in galaxy M82, a mere 11.4 million light years away from Earth, which means that it was close enough to be discovered by someone using an ordinary telescope in London and may be visible with binoculars sometime in the next two weeks.
M82’s proximity means that there are many existing images of it, pre-explosion, including some from the Hubble Space Telescope. Cao and others will comb through those images, looking for what lay in the region before. It will not be easy: M82 is filled with dust. But the light the supernova shines on the dust could teach astronomers something about the host galaxy, too. One team is already looking for radioactive elements, such as nickel, that theories predict form in such supernova, says Shri Kulkarni, an astronomer at California Institute of Technology. “Dust has its own charms.”
Ok, it didn’t erupt recently. M82 is 11.4 million light years away, so the supernova happened 11.4 million years ago and the light is just now reaching us here on Earth.↩
Sheryl Canter extensively researched the best way to season a cast iron pan and here is what she recommends you do. (Because science.)
I’ve read dozens of Web pages on how to season cast iron, and there is no consensus in the advice. Some say vegetable oils leave a sticky surface and to only use lard. Some say animal fat gives a surface that is too soft and to only use vegetable oils. Some say corn oil is the only fat to use, or Crisco, or olive oil. Some recommend bacon drippings since lard is no longer readily available. Some say you must use a saturated fat — that is, a fat that is solid at room temperature, whether it’s animal or vegetable (palm oil, coconut oil, Crisco, lard). Some say never use butter. Some say butter is fine. Some swear by Pam (spray-on canola oil with additives). Some say the additives in Pam leave a residue at high temperatures and pure canola oil is best. Some say it doesn’t matter what oil you use.
They are all wrong. It does matter what oil you use, and the oil that gives the best results is not in this list. So what is it? Here are some hints: What oil do artists mix with pigment for a high quality oil paint that dries hard and glassy on the canvas? What oil is commonly used by woodturners to give their sculptures a protective, soft-sheen finish? It’s the same oil. Now what is the food-grade equivalent of this oil?
The oil used by artists and woodturners is linseed oil. The food-grade equivalent is called flaxseed oil. This oil is ideal for seasoning cast iron for the same reason it’s an ideal base for oil paint and wood finishes. It’s a “drying oil”, which means it can transform into a hard, tough film. This doesn’t happen through “drying” in the sense of losing moisture through evaporation. The term is actually a misnomer. The transformation is through a chemical process called “polymerization”.
Those before and after photos are hard to argue with. (via @akuban)
Update: Canter wrote a bit more about seasoning and added an extra step to the process. (via @_Atticus)
Scientists at the University of Vermont’s Proctor Maple Research Center have made an interesting discovery. It seems that the sap used to produce maple syrup doesn’t flow from the tops of trees, it gets sucked up from the trees’ roots. Which means that maple syrup makers can use saplings instead of fully grown maple trees to produce syrup.
They realized that their discovery meant sugarmakers could use saplings, densely planted in open fields, to harvest sap. In other words, it is possible that maple syrup could now be produced as a row crop like every other commercial crop in North America.
In a natural forest, which varies in maple density, an average 60 to 100 taps per acre will yield 40 to 50 gallons of syrup. According to the researchers’ calculations, an acre of what is now called “the plantation method” could sustain 5,800 saplings with taps yielding 400 gallons of syrup per acre. If the method is realized, producing maple syrup on a commercial scale may no longer be restricted to those with forest land; it could require just 50 acres of arable land instead of 500 acres of forest. Furthermore, any region with the right climate for growing maples would be able to start up maple “farms”. The natural forest would become redundant.
(via @youngna)
First of all, how cute are these foxes jumping up and diving down into the snow after mice?
So. Cute. Here’s Robert Krulwich on what they’re up to:
Think about this … an ordinary fox can stalk a mole, mouse, vole or shrew from a distance of 25 feet, which means its food is making a barely audible rustling sound, hiding almost two car lengths away. And yet our fox hurls itself into the air — in an arc determined by the fox, the speed and trajectory of the scurrying mouse, any breezes, the thickness of the ground cover, the depth of the snow — and somehow (how? how?), it can land straight on top of the mouse, pinning it with its forepaws or grabbing the mouse’s head with its teeth.
Look at those ears and how the fox moves his head around to zero in on the mouse’s location…reminds me of the pre-radar acoustic location devices (sometimes called war tubas) used in the early 20th century to detect approaching aircraft:
Let slip the tubas of war! Aaaaanyway, as the acoustic location device gave way to the more effective radar, so too is the fox more successful at hunting when he is pointed northeast — a kind of magnetic radar, if you will. Fascinating.
A pair of scientists recently searched the internet for evidence of time travel.
Here, three implementations of Internet searches for time travelers are described, all seeking a prescient mention of information not previously available. The first search covered prescient content placed on the Internet, highlighted by a comprehensive search for specific terms in tweets on Twitter. The second search examined prescient inquiries submitted to a search engine, highlighted by a comprehensive search for specific search terms submitted to a popular astronomy web site. The third search involved a request for a direct Internet communication, either by email or tweet, pre-dating to the time of the inquiry. Given practical verifiability concerns, only time travelers from the future were investigated.
Spoiler: they didn’t find any. (via @CharlesCMann)
Inspired by the escalating blade count of the razor industry, Nabisco has developed a new snack called the Quadriscuit.
“At the moment, this hyperwafer can only exist for six milliseconds in a precisely calibrated field of magnetic energy, positrons, roasted garlic, and beta particles,” lab chief Dr. Paul Ellison told reporters at a press conference outside Nabisco’s $200 million seven-whole-grain accelerator.
The last line of the piece made me LOL for real. (thx, meg)
In a feature straight out of the movies, Dr. Rob Jenkins and his team have demonstrated that for sufficiently high-resolution photos, recognizable images of reflected faces of the photographer and bystanders can be retrieved from a subject’s eyes.
The researchers say that in crimes in which the victims are photographed, such as hostage taking or child sex abuse, reflections in the eyes of the photographic subject could help to identify perpetrators. Images of people retrieved from cameras seized as evidence during criminal investigations could be used to piece together networks of associates or to link individuals to particular locations.
By zooming in on high-resolution passport-style photographs, Jenkins and co-researcher Christie Kerr of the School of Psychology, University of Glasgow were able to recover bystander images that could be identified accurately by observers, despite their low resolution.
Here’s some older research about reading confidential data using reflections from tea pots, glasses, eyes, and even diffuse materials like fabric. And of course, there’s the famous eBay tea kettle. (via waxy)
Plants eat light, grow almost everywhere on Earth, and make up 99% of the planet’s biomass. But do what extent do plants think? Or feel? Michael Pollan tackles the question of plant intelligence in a thought-provoking article for the New Yorker (sadly behind their paywall).
Indeed, many of the most impressive capabilities of plants can be traced to their unique existential predicament as beings rooted to the ground and therefore unable to pick up and move when they need something or when conditions turn unfavorable. The “sessile life style” as plant biologists term it, calls for an extensive and nuanced understanding of one’s immediate environment, since the plant has to find everything it needs, and has to defend itself, while remaining fixed in place. A highly developed sensory apparatus is required to locate food and identify threats. Plants have evolved between fifteen and twenty different senses, including analogues of our five: smell and taste (they sense and respond to chemicals in the air or on their bodies); sight (they react differently to various wavelengths of light as well as to shadow); touch (a vine or root “knows” when it encounters a solid object); and, it has been discovered, sound.
In a recent experiment, Heidi Appel, a chemical ecologist at the University of Missouri, found that, when she played a recording of a caterpillar chomping a leaf for a plant that hadn’t been touched, the sound primed the the plant’s genetic machinery to produce defense chemicals. Another experiment, dome in Mancuso’s lab and not yet published, found that plant roots would seek out a buried pipe through which water was flowing even if the exterior of the pipe was dry, which suggested that plants somehow “hear” the sound of flowing water.
One of the researchers featured in the article, Stefano Mancuso, has a TED talk available in which he outlines his case for plant intelligence:
The article also discusses if plants have feelings. If so, should we feel bad that our wifi routers might kill plants?
Update: Mancuso and Alessandra Viola have collaborated on a new book about the intelligence of plants, Brilliant Green: The Surprising History and Science of Plant Intelligence.
There’s art on the Moon, a small sculpture called Fallen Astronaut. Artist Paul van Hoeydonck made it. Commander David Scott of Apollo 15 placed it on the Moon in 1971. Instead of a triumph, the whole thing fell into scandal and was forgotten.
In reality, van Hoeydonck’s lunar sculpture, called Fallen Astronaut, inspired not celebration but scandal. Within three years, Waddell’s gallery had gone bankrupt. Scott was hounded by a congressional investigation and left NASA on shaky terms. Van Hoeydonck, accused of profiteering from the public space program, retreated to a modest career in his native Belgium. Now both in their 80s, Scott and van Hoeydonck still see themselves unfairly maligned in blogs and Wikipedia pages-to the extent that Fallen Astronaut is remembered at all.
And yet, the spirit of Fallen Astronaut is more relevant today than ever. Google is promoting a $30 million prize for private adventurers to send robots to the moon in the next few years; companies such as SpaceX and Virgin Galactic are creating a new for-profit infrastructure of human spaceflight; and David Scott is grooming Brown University undergrads to become the next generation of cosmic adventurers.
Governments come and go, public sentiment waxes and wanes, but the dream of reaching to the stars lives on. Fallen Astronaut does, too, hanging eternally 238,000 miles above our heads. Here, for the first time, we tell the full, tangled tale behind one of the smallest yet most extraordinary achievements of the Space Age.
In a fly-by of Earth on its way to Jupiter, NASA’s Juno probe took a short movie of the Moon orbiting the Earth. It’s the first time the Moon’s orbit has been captured on film.
(via @DavidGrann)
Using a large piece of spandex (representing spacetime) and some balls and marbles (representing masses), a high school science teacher explains how gravity works.
The bits about how the planets all orbit in the same direction and the demo of the Earth/Moon orbit are really neat. And you can stop watching around the 7-minute mark…the demos end around then.
Update: Here’s another video of a similar system with some slightly different demos.
From a blog about the science of dogs, a comparison of photos of purebred dogs from 1915 to those of today. You can see how much the dogs have changed in just under 100 years, in some cases for the worse. For instance, the difference in the Bull Terrier (aka the Spuds MacKenzie dog) is marked and a bit disturbing:
Pure breeding has also introduced medical problems for some breeds.
The English bulldog has come to symbolize all that is wrong with the dog fancy and not without good reason; they suffer from almost every possible disease. A 2004 survey by the Kennel Club found that they die at the median age of 6.25 years (n=180). There really is no such thing as a healthy bulldog. The bulldog’s monstrous proportions makes them virtually incapable of mating or birthing without medical intervention.
(via @mulegirl)
Your body clock alarm is just as accurate as the one on your phone: your body naturally takes note of what time you want to wake up and wakes you up.
There’s evidence you can will yourself to wake on time, too. Sleep scientists at Germany’s University of Lubeck asked 15 volunteers to sleep in their lab for three nights. One night, the group was told they’d be woken at 6 a.m., while on other nights the group was told they’d be woken at 9 a.m..
But the researchers lied-they woke the volunteers at 6 a.m anyway. And the results were startling. The days when sleepers were told they’d wake up early, their stress hormones increased at 4:30 a.m., as if they were anticipating an early morning. When the sleepers were told they’d wake up at 9 a.m., their stress hormones didn’t increase — and they woke up groggier. “Our bodies, in other words, note the time we hope to begin our day and gradually prepare us for consciousness,” writes Jeff Howe at Psychology Today.
(via digg)
From Wikipedia, a list of products and technologies that have been developed with the help of NASA, including memory foam, Dustbusters, and powdered lubricants.
For more than 50 years, the NASA Innovative Partnerships Program has connected NASA resources to private industry, referring to the commercial products as spin-offs. Well-known products that NASA claims as spin-offs include memory foam (originally named temper foam), freeze-dried food, firefighting equipment, emergency “space blankets”, Dustbusters, cochlear implants, and now Speedo’s LZR Racer swimsuits. NASA claims that there are over 1650 other spin-offs in the fields of computer technology, environment and agriculture, health and medicine, public safety, transportation, recreation, and industrial productivity.
NASA did not, however, invent Teflon or Velcro. (via @tangentialism)
Hans Bethe was a giant in the field of nuclear physics. He rubbed shoulders with Einstein, Bohr, and Pauli, was head of the Theoretical Division of the US atomic bomb project, and was awarded a Nobel Prize. In 1999, at the age of 93, Bethe gave a series of three lectures to the residents of his retirement community near Cornell University, where he had taught since 1935. Video of the lectures is available on the Cornell website.
In the first lecture, Bethe covers the development of the “old quantum theory”, covering the work of Max Planck and Niels Bohr. In the second and third lectures, he relates how modern quantum mechanics was developed, with a healthy amount of personal recollection along the way:
Professor Bethe offers personal anecdotes about many of the famous names commonly associated with quantum physics, including Bohr, Heisenberg, Born, Pauli, de Broglie, Schrödinger, and Dirac.
Without a doubt, this is the most high-power presentation ever made at a retirement home. (via @stevenstrogatz)
Google and NASA recently bought a D-Wave quantum computer. But according to a piece by Sophie Bushwick published on the Physics Buzz Blog, there isn’t scientific consensus on whether the computer is actually using quantum effects to calculate.
In theory, quantum computers can perform calculations far faster than their classical counterparts to solve incredibly complex problems. They do this by storing information in quantum bits, or qubits.
At any given moment, each of a classical computer’s bits can only be in an “on” or an “off” state. They exist inside conventional electronic circuits, which follow the 19th-century rules of classical physics. A qubit, on the other hand, can be created with an electron, or inside a superconducting loop. Obeying the counterintuitive logic of quantum mechanics, a qubit can act as if it’s “on” and “off” simultaneously. It can also become tightly linked to the state of its fellow qubits, a situation called entanglement. These are two of the unusual properties that enable quantum computers to test multiple solutions at the same time.
But in practice, a physical quantum computer is incredibly difficult to run. Entanglement is delicate, and very easily disrupted by outside influences. Add more qubits to increase the device’s calculating power, and it becomes more difficult to maintain entanglement.
(via fine structure)
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