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Quantum Entanglement Could Stretch Across Time

Quantum Entanglement Could Stretch Across Time
In the weird world of quantum physics, two linked particles can share a single fate, even when they’re miles apart. Now, two physicists have mathematically described how this spooky effect, called entanglement, could also bind particles across time. If their proposal can be tested, it could help process information in quantum computers and test physicists’ basic understanding of the universe. “You can send your quantum state into the future without traversing the middle time,” said quantum physicist S. Jay Olson of Australia’s University of Queensland, lead author of the new study. In ordinary entanglement, two particles (usually electrons or photons) are so intimately bound that they share one quantum state — spin, momentum and a host of other variables — between them. Physicists have figured out how to use entanglement to encrypt messages in uncrackable codes and build ultrafast computers. Olson explained them with a Star Trek analogy. “It stimulated our imaginations,” said Fuentes. Related:  Quantumly

Multiple Asteroid Strikes May Have Killed Mars’s Magnetic Field | Wired Science Once upon a time, Mars had a magnetic field, just like Earth. Four billion years ago, it vanished, taking with it the planet’s chances of evolving life as we know it. Now scientists have proposed a new explanation for its disappearance. A model of asteroids striking the red planet suggests that, while no single impact would have short-circuited the dynamo that powered its magnetism, a quick succession of 20 asteroid strikes could have done the job. “Each one crippled a little bit,” said geophysicist Jafar Arkani-Hamed of the University of Toronto, author of the new study. “We believe those were enough to cripple, cripple, cripple, cripple until it killed all of the dynamo forever.” Rocky planets like Earth, Mars, Mercury and even the moon get their magnetic fields from the movement of molten iron inside their cores, a process called convection. But Arkani-Hamed’s new study in the Journal of Geophysical Research suggests that just one impact wouldn’t suffice. Image: NASA See Also:

Himalayan Glaciers Shrinking, With Some Exceptions | Wired Science An important portion of the Himalaya’s glacier cover is currently stable and, thanks to an insulating layer of debris, may be even growing, a new study finds. The study’s conclusion contradicts a portion of the 2007 Intergovernmental Panel on Climate Change report that had to be retracted last year because it could not be substantiated. Though the IPCC report stated that the risk of the region’s glaciers “disappearing by the year 2035 and perhaps sooner is very high,” the new study finds that ice cover is stable in the Karakoram mountains, a northern range that holds about half of the Himalaya’s store of frozen water. That’s not to imply that water reservoirs on what’s often called the roof of the world aren’t under stress. Scherler’s team pored over satellite images of 286 glaciers throughout the Himalayas. Indeed, for much of the past century Karakoram’s glaciers were in retreat. In general, the warmer the air above a glacier becomes the faster exposed ice will melt. See Also:

A Step Towards Quantum Computing: Entangling 10 Billion Particles | 80beats In life, most people try to avoid entanglement, be it with unsavory characters or alarmingly large balls of twine. In the quantum world, entanglement is a necessary step for the super-fast quantum computers of the future. According to a study published by Nature today, physicists have successfully entangled 10 billion quantum bits, otherwise known qubits. But the most significant part of the research is where the entanglement happened–in silicon–because, given that most of modern-day computing is forged in the smithy of silicon technology, this means that researchers may have an easier time incorporating quantum computers into our current gadgets. Quantum entanglement occurs when the quantum state of one particle is linked to the quantum state of another particle, so that you can’t measure one particle without also influencing the other. Spinning particles are all well and nice, but what do they have to do with computing? Image: Stephanie Simmons

Op-Ed: The Mass Extinction of Scientists Who Study Species | Wired Science We are currently in a biodiversity crisis. A quarter of all mammals face extinction, and 90 percent of the largest ocean fish are gone. Species are going extinct at rates equaled only five times in the history of life. Scientists who classify, describe and examine the relationships between organisms are themselves going extinct. Take for example the aplacophorans, a rare rare group of invertebrates closely related to octopuses, squids, snails and clams. Fewer than two dozen scientific papers have been published on the group since 2005, even though many new species await discovery and description. If 50 percent of the species of aplacophoran went extinct tomorrow, we would never know. Amelie’s story is tragically common. Both kinorhynchs and gnathostomulids are small, less than one-tenth of an inch in length, and dwell in between grains of sand and mud on the ocean floor. Aplacophorans This problem plagues well-known groups, too. Why the loss of taxonomists? Why?

New Doubts Raised About Potential Bee-Killing Pesticide | Wired Science A federal entomologist has become the latest researcher to voice doubts about neonicotinoids, a controversial new type of pesticide that may be linked to the collapse of honeybee populations in the United States. The Independent reports that in a documentary screened in Europe but not yet broadcast stateside, USDA bee specialist Jeffrey Pettis describes exposing two groups of bees, one dosed with a neonicotinoid called imidacloprid, to Nosema, a common honeybee disease. Pesticide-dosed bees proved especially vulnerable to infection. Imidacloprid is manufactured by German agrochemical Bayer, who also manufacture clothianidin, another neonicotinoid. Since its approval, clothianidin has become widespread. Correlation isn’t cause, but there are already grounds for concern about clothianidin. “Clothianidin’s major risk concern is to non-target insects (that is, honey bees),” wrote those researchers. Image: Flickr, Jack Wolf See Also:

Quantum Entanglement Whatever happened to one particle would thus immediately affect the other particle, wherever in the universe it may be. Einstein called this "Spooky action at a distance." Amir D. Aczel, Entanglement, The Greatest Mystery In Physics. The Theory When a photon (usually polarized laser light) passes through matter, it will be absorbed by an electron. When the original photon splits into two photons, the resulting photon pair is considered entangled. The process of using certain crystals to split incoming photons into pairs of photons is called parametric down-conversion. Normally the photons exit the crystal such that one is aligned in a horizontally polarized light cone, the other aligned vertically. To illustrate, if an entangled photon meets a vertical polarizing filter (analagous to the fence in Figure 4.4), the photon may or may not pass through. The Practice Experiments have shown that Einstein may have been wrong: entangled photons seem to communicate instantaneously. Figure 5.1.

Sleeping Protects Memories From Corruption | Wired Science “You must remember this,” Sam the piano player crooned to Humphrey Bogart and Ingrid Bergman in Casablanca. The couple might have recalled even more about their days in Paris if they’d been napping when Sam played the tune again. Replaying memories while people are awake leaves their memories subject to tinkering. But reactivating memories during sleep protects them from interference, researchers in Germany and Switzerland report online January 23 in Nature Neuroscience. The finding shows that the brain handles memories differently during sleep than while awake, says Sara Mednick, a cognitive neuroscientist at the University of California, San Diego who was not involved in the research. In the new study, volunteers played a Concentration-type game in which they had to remember the locations of pairs of cards. Both sleeping and awake volunteers who didn’t have their memories jogged by the odor remembered about 60 percent of the pairs. Image: Flickr/mollyollyoxenfree See Also:

To Learn Best, Write an Essay | Wired Science Trying to remember what you’ve just studied, then writing it down, may be a surprisingly good way to learn. In a study published January 21 in Science, researchers asked 200 college students to spend five minutes reading a short passage about a scientific subject. Afterwards, they were either told to re-read it several times, as if cramming for a test; make “concept maps” of the material; or spend 10 minutes writing a free-form essay about the passage. One week later, the students were given short-answer tests on what they remembered, and asked to draw logical conclusions from those facts. Students were then asked to draw concept maps from memory, and the essay-writers again did best, beating those students who made concept maps the first time around. The findings are necessarily limited, but do suggest that retrieval practice, as the essay-writing was called, is a powerful learning tool. However, concept mapping and cramming did prove useful in at least one way. See Also:

Bibliography of Quantum Cryptography by Gilles Brassard Département IRO, Université de Montréal. The original PostScript file from Gilles Brassard - provided by Edith Stoeveken - was converted to ASCII and reformatted in HTML; Sept 2 1994, Stephan Kaufmann. Abstract This paper provides an extensive annotated bibliography of papers that have been written on quantum cryptography and related topics. 1. For ages, mathematicians have searched for a system that would allow two people to exchange messages in perfect privacy. In addition to key distribution, quantum techniques may also assist in the achievement of subtler cryptographic goals, important in the post-cold war world, such as protecting private information while it is being used to reach public decisions. In the past few years, a remarkable surge of interest in the international scientific and industrial community has propelled quantum cryptography into mainstream computer science and physics. 2. Quantum cryptography is best known for key distribution. 3. 4. 5. 6. 7.

New Study Finds No Sign of ‘First Habitable Exoplanet’ | Wired Science Things don’t look good for Gliese 581g, the first planet found orbiting in the habitable zone of another star. The first official challenge to the small, hospitable world looks in the exact same data — and finds no significant sign of the planet. “For the time being, the world does not have data that’s good enough to claim the planet,” said astro-statistics expert Philip Gregoryof the University of British Columbia, author of the new study. The “first habitable exoplanet” already has a checkered history. Planet G was the sixth planet found circling Gliese 581, a red dwarf star 20 light-years from Earth. Two more planets, including the supposedly habitable 581g, appeared when astronomers Steve Vogt of the University of California, Santa Cruz and Paul Butler of the Carnegie Institution of Washington added data from the HIRES spectrograph on the Keck Telescope in Hawaii. Now, the first re-analysis of the combined data from both telescopes is out, and the planet is still missing. See Also:

Slime Molds Are Earth’s Smallest, Oldest Farmers | Wired Science Colonies of a bizarre microbial goo have been found practicing agriculture at a scale tinier than any seen before. Animals such as ants, snails and beetles are known to farm fungus. But the slime mold’s bacterial-farming trick takes it into a whole new realm.. “If you can pack your food source with you, it’s a serious advantage,” said molecular biologist Debra Brock of Rice University, co-author of the slime-mold study, published Jan. 19 in Nature. Dictyostelium discoideum, the best-known of a group of creatures called slime molds, spends part of its life as a single-celled amoeba feeding on bacteria that grow in decomposing leaves on forest floors. When food is short, hundreds of thousands of amoebas come together, fusing into a single entity. It’s been thought that slime molds simply scavenge, eating bacteria they like and oozing out the rest. When grown in the lab, the unusual fruiting bodies grew both the slime mold and the bacteria. See Also: