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Math

Submission + - Do quantum laws give rise to our classical world? (physorg.com)

Submitted by
kfz versicherung
kfz versicherung writes: "Quantum physics forbids that quantum mechanics works on a macro level in the classical world. Now Kofler and Brukner demonstrated that the time evolution of a quantum system, no matter how macroscopic the system is, cannot be treated in a classical sense. "Just because something is big doesn't mean it can be described by classical physics." Then referring back to the case of spin, he continues: "Arbitrarily large spins can still have a quantum time evolution and violate the Leggett-Garg inequality." Next, the two realized that coarse-grained measurements are used in realistic conditions, such as situations that we are confronted with every day, as the resolution of the apparatuses usually is limited. "If you are bound to restrict yourself to coarse-grained measurements of the spin," Kofler explains, "you get the classical Newtonian laws of motion.""
Security

Submission + - Wikileaks.org Down

Submitted by Anonymous Coward
An anonymous reader writes: Wikileaks is a website running on modified MediaWiki software which allows whistleblowers to anonymously release government and corporate documents, allegedly without possible retribution. It claims that postings are untraceable by anyone attempting to do so. Since a few days ago Wikileaks published US government documents about Guantanamo Operating Procedures and Iraq equipment and was subsequently apparently taken down. The Chinese government currently attempts to censor every web site with "wikileaks" in the URL, and now it seems USA has joined them.
Space

Submission + - Watching earthrise from moon (www.jaxa.jp)

Submitted by
kfz versicherung
kfz versicherung writes: "Japan's Kaguya spacecraft has captured a stunning video of the Earth rising above the horizon and setting again as the spacecraft orbits around the Moon. Sadly earthrise cannot be viewed from the surface of the Moon. That's because one side of the Moon is permanently locked facing the Earth, so Earth stays fixed in the Moon's sky (or below the horizon on the side facing away from Earth). Download the high-definition videos from offical JAXA website."
Hardware Hacking

Submission + - Researchers capture exotic radioactivity on camera (physorg.com)

Submitted by
kfz versicherung
kfz versicherung writes: "Until now, measuring fleeting, exotic nuclei has been largely impossible. Understanding of the exotic form of radioactivity of the iron-45 isotope has thus been poor. A novel combination of advanced physics equipment and imaging technology found in most off-the-shelf digital cameras has done the trick. 'We have proven in a direct and clear way that this extremely neutron-deficient nucleus disintegrates by the simultaneous emission of two protons,' one of the researchers is quoted."
Announcements

Submission + - The small line between quantum and classical world (physorg.com)

Submitted by
kfz versicherung
kfz versicherung writes: "On what scale do the quantum world and the classical world begin to cross into each other? How big does an "observer" have to be? It's a long-argued question of fundamental scientific interest and practical importance as well, with significant implications for attempts to build solid-state quantum computers. Researchers at the Department of Energy's Lawrence Berkeley National Laboratory and their collaborators at the University of Frankfurt, Germany; Kansas State University; and Auburn University have now established that quantum particles start behaving in a classical way on a scale as small as a single hydrogen molecule. They reached this conclusion after performing what they call the world's simplest — and certainly its smallest — double slit experiment, using as their two "slits" the two proton nuclei of a hydrogen molecule, only 1.4 atomic units apart (a few ten-billionths of a meter)."
Math

Submission + - Possible backdoor found in RNG standardizedby NSA (schneier.com) 1

Submitted by
kfz versicherung
kfz versicherung writes: "Defining algorithm for random numbers is one of the hardest fields in mathematics. We all know Microsoft failed miserably, even Linux (pdf) and SSL had their fair share of troubles. But now Bruce Schneier tells us the Strange Story of Dual_EC_DRBG, one of four random number generation algorithms standardized by the NSA (pdf). While on first look just slower than the other three, Dan Shumow and Niels Ferguson showed at Crypto 2007 that the algorithm contains a weakness that can only be described a backdoor. Their presentation showed that the constants used have a relationship with a second, secret set of numbers that can act as a kind of skeleton key. If you know the secret numbers, you can predict the output of the random-number generator after collecting just 32 bytes of its output."
Space

Submission + - Rosetta craft interpreted as interplanetary thread (newscientist.com)

Submitted by
kfz versicherung
kfz versicherung writes: "An asteroid tracking system interpreted the Rosetta spacecraft as an incoming rock last week and issued an alert that a near-miss was looming. Three U.S. observatories spotted an unidentified object heading Earth's way. The observation prompted the Minor Planet Center at the Harvard Smithsonian Center for Astrophysics in Cambridge, Mass., which coordinates the search of near-Earth objects, to issue a potential near-miss warning. The warning was retracted after astronomer Denis Denisenko in Moscow noticed the object's trajectory closely matched Rosetta's."
Space

Submission + - Strange new space weather phenomen discovered (physorg.com) 1

Submitted by
kfz versicherung
kfz versicherung writes: "Something strange is happening in the atmosphere above Africa and researchers have converged on Addis Ababa, Ethiopia, to discuss the phenomenon. Researchers liken the plumes to smoke billowing out of a factory smokestack — except instead of ordinary ash and dust, ion plumes are made of electrified gas floating so high above ground they come in contact with space itself. "The plumes appear during geomagnetic storms and they can interfere with satellite transmissions, airline navigation and radio communications," says Fuller-Rowell. Indeed, it is their effect on GPS signals that led to the discovery of plumes over North America just a few years ago."
Space

Submission + - China launches probe in Asian race for moon (google.com)

Submitted by
kfz versicherung
kfz versicherung writes: "According to Chinese news agency Xinhua, China successfully launched its first lunar probe on Wednesday. The Chang'e I blasted off at about 6:05 pm on a Long March 3A carrier rocket from the No. 3 launching tower in the Xichang Satellite Launch Center in Southwest China's Sichuan Province. The mission named after a Chinese goddess who, in a popular fairy tale, lives on the Moon, carries a satellite based on China's Dongfanghong 3 telecommunication satellite platform and reportedly carries a 280-pound (127-kilogram) payload of science instruments for its planned one-year mission."
Security

Submission + - Apple Adds Memory Randomization (ALSR) to Leopard

Submitted by
.mack
.mack writes: "Apple has announced plans to add code-scrambling diversity to Mac OS X Leopard, a move aimed at making the operating system more resilient to virus and worm attacks. The security technology, known as ASLR (address space layout randomization), randomly arranges the positions of key data areas to prevent malware authors from predicting target addresses. Another new feature coming in Leopard is Sandboxing (systrace), which limits an application's access to the system by enforcing access policies for system calls."

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