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An enormous helium balloon floating about 24 miles above Antarctica has detected a mix of high-energy electrons so exotic that researchers say the particles must have been created by some fascinating process: They may have been formed when dark matter particles collided and annihilated each other, or else a surprisingly close astronomical object like a pulsar could be spitting the electrons at Earth.

Researchers can’t yet determine which answer is correct, but say the dark matter explanation is more exciting. Dark matter is one of astrophysics’ greatest enigmas. It is thought to be five times more common than visible matter, but there is no proof of what it is made of. The existence of dark matter has largely been inferred from its gravitational effects, such as the fact that most galaxies have enough mass to remain as well-defined objects despite having too little visible matter to account for the necessary gravity [National Geographic News]. If the research balloon did detect the signature of dark matter through the particles left over from collisions, it would be the closest researchers have ever gotten to seeing the mysterious stuff.

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Fixing the glitches that shut down the Large Hadron Collider (LHC) in September will apparently be no easy task: A spokesman for the particle physics lab CERN has announced that the repairs will cost $21 million and will probably not be completed until late June. Cern spokesman James Gillies said: “If we can do it sooner, all well and good. But I think we can do it realistically (in) early summer” [BBC News].

The startup of the LHC on September 10th may win an award for anticlimax of the year: Physicists talked for months about the mysteries of physics that the particle collider would reveal, while nervous laypeople worried that when engineers flipped the switch on the machine it would create a miniature black hole that could destroy the earth. But instead of either of these scenarios coming true, the LHC broke within two weeks before getting a chance to perform any experiments.

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Strange things are afoot at the Tevatron particle collider at Fermilab, and the aging U.S. particle smasher is getting an unexpected moment in the spotlight while physicists wait for the repairs of the Large Hadron Collider in Switzerland. Researchers say experiments at the Tevatron have produced particles that they are unable to explain using the standard model of physics, and say it’s possible that they’ve detected a previously unknown particle. If the result does turn out to be due to some unexpected new process, it would be the most significant discovery in particle physics for decades [Physics World].

Bloggers and theorists are already lining up explanations that involve unseen particles, hypothetical strings, or modifications of conventional physics. The finding is so controversial that about one-third of the 600-person experiment that detected it are refusing to put their names on the 69-page paper purporting its discovery [Nature News], which was posted in advance of publication on the server arXiv.

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Peeling a roll of ordinary sticky tape can generate 100 milliwatt pulses of X-rays, enough to capture a human finger on X-ray film, according to a new study by UCLA scientists. They claim to have found the cheapest way to produce X-rays of that scale. “At some point we were a little bit scared,” says Juan Escobar, a member of the research team. But he and his co-workers soon realized that the X-rays were only emitted when the kit was used in a vacuum [Nature News].

Their kit consisted of a vacuum-enclosed machine, reminiscent of a video casette player, that peeled a roll of Photo Safe 3M Scotch tape at a rate of 3 cm per second. Rapid pulses of X-rays, each about a billionth of a second long, emerged from very close to where the tape was coming off the roll. That’s where electrons jumped from the roll to the sticky underside of the tape that was being pulled away, a journey of about two-thousandths of an inch, Escobar said. When those electrons struck the sticky side they slowed down, and that slowing made them emit X-rays [AP]. This type of energy release is known as triboluminescence — the same principle behind the fun trick of crunching on Wint-O-Green Live Savers to produce blue sparks.

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Encryption systems that rely on the “spooky” properties of quantum mechanics have long been hyped as the ultimate in spy- and hack-proof communication, and recently governments and large companies have begun sampling early examples of the technology. Now, scientists in Vienna have demonstrated a commercial telecommunications network protected by quantum cryptography, and say the system could be generally available in less than 10 years.

One of the researchers who worked out the basic idea behind quantum cryptography 25 years ago, Gilles Brassard, was on hand in Vienna to explain the mechanism. “All quantum security schemes are based on the Heisenberg Uncertainty Principle, on the fact that you cannot measure quantum information without disturbing it,” he explained. “Because of that, one can have a communications channel between two users on which it’s impossible to eavesdrop without creating a disturbance. An eavesdropper would create a mark on it. That was the key idea” [BBC News].

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Three scientists who probed the mysteries of particle physics have been awarded the Nobel Prize in physics, the Royal Swedish Academy of Sciences announced today. The winners are Yoichiro Nambu, a Tokyo-born American citizen, and Makoto Kobayashi and Toshihide Maskawa of Japan. Nambu identified a mechanism called spontaneous broken symmetry in subatomic physics. Kobayashi and Maskawa work predicted the existence of three families of elementary particles known as quarks. According to the Standard Model of particle physics, quarks are the sub-units of protons and neutrons, which together make up the nuclei of atoms [BBC News].

“Spontaneous broken symmetry conceals nature’s order under an apparently jumbled surface,” the academy said in its citation. “Nambu’s theories permeate the standard model of elementary particle physics. The model unifies the smallest building blocks of all matter and three of nature’s four forces in one single theory.” Kobayashi and Maskawa “explained broken symmetry within the framework of the standard model but required that the model be extended to three families of quarks” [AP].

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The accident that brought the Large Hadron Collider’s particle-smashing experiments to a screeching halt on Friday will keep the collider out of action until spring 2009, officials at CERN announced today. A preliminary inquiry has revealed that it will take two months to fix the problem and restore operating conditions, and the LHC was already scheduled to shut down in the winter to reduce electrical costs.

Says CERN spokesman James Gillies: “We are not going to be done with this before the winter shutdown, so there will be no more beam in the LHC this year…. The winter shutdown will go according to schedule, which means that we start up the accelerator complex in the spring months” [AP].

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The vaunted Large Hadron Collider (LHC) experienced a significant setback this morning, when temperatures in one sector of the particle collider began to rise, and a ton of liquid helium escaped into one area of the collider’s 17-mile tunnel. The mishap follows a previous glitch that occurred one day after the LHC’s opening and delayed operations for about a week, but this new incident appears to be more serious and could take several weeks to resolve.

The LHC smashes subatomic particles together by send protons whizzing through its circular tunnel to collide at certain points; the beams of protons are kept on track by over 1,600 massive magnets that must be kept at temperature near zero on the Kelvin scale. The incident was what is known as a “quench”, in which the temperature of superconducting magnets that are normally chilled to 1.9C above absolute zero started to rise. It caused the temperature of many of the 200 or so magnets in the affected sector to soar by as much as 100C, which would normally take about two weeks to be cooled again [The Times]. The LHC’s operating organization, known as CERN, hasn’t yet revealed the cause of the incident.

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Today at 10 a.m. Swiss time, researchers fired up the Large Hadron Collider (LHC), successfully sending a stream of protons all the way around a 17-mile track for the first time. The enormous collider has been eagerly anticipated by physicists, who hope the device will answer questions about the behavior of subatomic particles and reveal secrets of the universe, but some people have also worried (needlessly, physicists say) that its unprecedented experiments will cause the world to end. For all that hype, the action today was somewhat anticlimatic: Two white dots flashed on a computer screen indicating that the protons reached the final point of the world’s largest particle collider [AP].

As many scientists have pointed out, today’s test run didn’t involve any actual collisions; those will come later when particles shoot around the track in both directions and smash into each other. Therefore today’s event could never have produced any breathtaking results, it was simply intended to test the equipment.

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It may not be a big market, but it’s presumably a lucrative one: To meet the needs of consumers who are in the business of transmitting classified national secrets, physicists are working on an absolutely secure communication system that uses the strange laws of quantum mechanics to encode information. The latest experiments in this field, called quantum cryptography, produced a system that researchers say would theoretically work to transmit information around the globe.

The system relies on a concept known as quantum entanglement to establish hack-proof communication. Entanglement allows two particles to be quantum-mechanically connected even when they are physically separated. Although the specific condition of either particle cannot be precisely known, taking measurements of one will instantly tell you something about the other. The trick can’t be used to actually send information, because each particle’s condition is random until it is measured. But entanglement can be used for encrypting data if a sender and a receiver make measurements on a number of entangled particles and then compare their results [Nature News].

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The cosmic collision of two galaxy clusters has given astronomers a clearer look at the mysterious substance known as dark matter. Researchers say when the two clusters crashed into each other, the dark matter from each cluster [appeared] to pass through the cosmic mess unscathed, leaving ordinary matter behind in the galactic pileup [SPACE.com]. Using data from NASA’s Hubble and Chandra space telescopes, astronomers were able to produce an image showing clouds of dark matter, colored blue, on either side of the impact site.

Dark matter, mysterious stuff that exerts a gravitational force on other matter, was originally proposed to explain what holds spinning galaxies, like the Milky Way, together. Observations suggest it outweighs ordinary matter by a factor of about 6 to 1. But no one knows what it is made of, and normally dark matter and ordinary matter are too well mixed to observe the dark matter independently [New Scientist].

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Yesterday, NASA released the first set of images from its newest space telescope, the Gamma-Ray Large Area Space Telescope, which has now been renamed Fermi in honor of the particle physicist Enrico Fermi. After less than three months of collecting data, the Fermi telescope produced a map of the sky showing the sources of powerful gamma rays as bright spots of light.

“I like to call it our extreme machine,” said Jon Morse, the director of astrophysics for NASA. “It will help us crack the mysteries of these enormously powerful emissions.” Gamma rays are powerful light rays invisible to the naked eye [Washington Post]. As the Earth’s atmosphere absorbs gamma rays, they can only be studied from an orbiting telescope.

The $700 million telescope will observe gamma rays emitted by black holes, neutron stars, and other cosmic eccentrics, and will also scan the skies for the mysterious gamma ray bursts that are of special interest to astronomers because they are among the brightest events ever observed. The intense flashes of gamma rays can release within seconds the same amount of energy that the sun will put out over its entire ten-billion-year lifetime—but no one is sure what causes them. The going theory is that the bursts are tied to the explosive deaths of massive stars, but exactly what types of stars and how the explosions are triggered remains a mystery [National Geographic News]. Already, the Fermi telescope has detected gamma ray bursts at a rate of about one a day.

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After 15 years of construction, the world’s largest particle accelerator is warmed up, fully tested, and ready to rumble. The Large Hadron Collider will go into operation on September 10th, and researchers are celebrating every step towards that momentous day. Last weekend, physicists popped champagne to toast the results of a test in which beams of protons were sent barreling into a massive block of concrete, causing the protons to fragment into smaller particles. Researchers have also successfully sent test batches of protons part-way around the collider’s 17-mile circular track.

The Large Hadron Collider represents the science world’s latest, greatest attempt to smash its way into the mysteries of the universe: Beams of protons will eventually collide with the energy of two bullet trains - spawning sprays of subatomic debris that are certain to lead to new discoveries…. One experiment at the LHC, known as ALICE, seeks to re-create the conditions that existed just an instant after the big bang that gave rise to the universe as we know it. [The collider’s] researchers want to understand why matter won out over antimatter after the creation of the cosmos [MSNBC].

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Of all the weirdness in the universe, the quantum mechanics phenomenon called “entanglement” may be the most mind-boggling. Physicists have long shaken their heads at the theory that two particles that become entangled will always and instantly mirror each other’s properties, no matter how far they are separated, which seems to go against all other physical understanding. In the everyday world, objects can organize themselves in just a few ways. For example, two people can coordinate their actions by talking directly with each other, or they can both receive instructions from a third source…. But quantum mechanics allows for a third way to coordinate information [Nature News].

Einstein rebelled against the notion of quantum entanglement, derisively calling it “spooky action at a distance”  [LiveScience]. Entanglement would look a lot less spooky if we could prove that an entangled object releases an unknown particle or some other signal at high speeds to influence its partner, giving the illusion of a simultaneous reaction [LiveScience]. But a new study shows that if some hidden signal is passing between the separated particles, it would have to travel at 10,000 times the speed of light. As this explanation seems impossible, the research team favors the alternate, weirder idea: that a measurement on one photon instantly influences the other [New Scientist].

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Scientists at CERN had said all along that they planned to activate the Larger Hadron Collider this summer. Now it looks like they’ll slide in just before the official end of the season. The world’s most powerful particle accelerator, aimed at unlocking secrets of the universe, will be launched on September 10 [Reuters].

“We’re finishing a marathon with a sprint,” said project leader Lyn Evans. “It’s been a long haul, and we’re all eager to get the LHC research program under way” [San Jose Mercury News].

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