Can chaos theory teach us anything about international relations? This year marks that 50th anniversary of the branch of mathematics known as chaos theory. Appropriately enough for a field of study premised on the idea that seemingly insignificant events can have large and unpredictable consequences, the eureka moment of chaos is generally considered to be a short dense paper titled "Deterministic Nonperiodic Flow" published on page 130 of volume 20 of the Journal of the Atmospheric Sciences in 1963. As James Gleick writes in his very entertaining history, Chaos: Making of a New Science, "In the thousands of articles that made up the technical literature of chaos, few were cited more often than "Deterministic Nonperiodic Flow.
" For years, no single object would inspire more illustrations, even motion pictures, than the mysterious curve depicted at the end, the double spiral that became known as the Lorenz attractor. " The paper's author, Edward Lorenz, was an MIT mathematician working on an early computer weather modeling simulation. Yitang Zhang, twin primes conjecture: A huge discovery about prime numbers—and what it means for the future of math.
Photo courtesy of Lisa Nugent/UNH Photographic Services Last week, Yitang “Tom” Zhang, a popular math professor at the University of New Hampshire, stunned the world of pure mathematics when he announced that he had proven the “bounded gaps” conjecture about the distribution of prime numbers—a crucial milestone on the way to the even more elusive twin primes conjecture, and a major achievement in itself. The stereotype, outmoded though it is, is that new mathematical discoveries emerge from the minds of dewy young geniuses. But Zhang is over 50. What’s more, he hasn’t published a paper since 2001. Some of the world’s most prominent number theorists have been hammering on the bounded gaps problem for decades now, so the sudden resolution of the problem by a seemingly inactive mathematician far from the action at Harvard, Princeton, and Stanford came as a tremendous surprise.
But the fact that the conjecture is true was no surprise at all. Let’s start with what the conjectures say. Justin Read's Dark Matter Research Group Research. Dark matter appears to make up most of the mass in the Universe, yet it remains mysterious. Our best guess is that it is some new particle of nature that interacts only very weakly with photons. Although dark matter is almost perfectly invisible, we can still 'see' it through its gravitational influence. It raises the velocities of stars and gas in galaxies, bends light in massive galaxies and galaxy clusters, and promotes structure formation in the early Universe. Indeed, each of these gravitational effects allows us to actually image the distribution of dark matter on a range of scales.
Comparing these images with detailed computer simulations, we can constrain the nature of dark matter. This is a key goal of our group here at the ETH Zürich. Please click on the images above, or follow the links on the left, for further details of our research programme. Wichtiger Hinweis: Diese Website wird in älteren Versionen von Netscape ohne graphische Elemente dargestellt. Chinese top leaders call for innovation in science, technology. BEIJING, July 7 (Xinhua) -- China's top leaders have called for the country to become more innovative in science and technology, and for these systems to be reformed in a bid to build scientific power.
While attending the national conference on science and technology innovation held Friday and Saturday, President Hu Jintao stressed a strategy of invigorating the country with science and technology, as well as human resources. Hu also urged China to enhance its capacity for innovation in these fields, and to integrate science and technology with social and economic development.
"We must focus on promoting innovation in science and technology if we want to push forward reform and opening up policy, the modernization of socialism, and achieve the overall target for building a moderately prosperous society in an all-round way, improve the people's living standard, as well as achieve the great rejuvenation of the Chinese nation," said Hu at the conference. Quaternions. What is a quaternion? A quaternion is a mathematical abstraction just like a real number, complex number, tensor, or manifold. A quaternion is basically a type of complex number that consists of four values, one of which is real, while the other three are imaginary. As such, quaternions are referred to as hypercomplex numbers. So, just like a complex number consists of two parts (real and imaginary), the hypercomplex number consists of four parts (1 real and 3 imaginary). Several textbooks and internet references are available that provide detailed descriptions of quaternions, including mathematically rigorous derivations of all the relevant quaternion rules and formulas.
There are two common conventions for representing a quaternion: one has the real component first and the other has the real component last. Where, A quaternion can be normalized just like a four dimensional vector by dividing each of the four components by the Euclidean norm. Physical Interpretation Figure 20. Outstanding Referees Program. The Outstanding Referee program was instituted in 2008 to recognize scientists who have been exceptionally helpful in assessing manuscripts for publication in the APS journals. By means of the program, APS expresses its appreciation to all referees, whose efforts in peer review not only keep the standards of the journals at a high level, but in many cases also help authors to improve the quality and readability of their articles – even those that are not published by APS. The highly selective Outstanding Referee program annually recognizes about 150 of the roughly 60,000 currently active referees.
At the start of the program, in 2008 and 2009, larger groups were selected by our Editors for the Outstanding Referee designation, in order to "catch up" and recognize referees who had already served for many years. Like Fellowship in the APS, this is a lifetime award. The Outstanding Referees are to be congratulated and thanked for their outstanding service to the physics community. Quantum computer built inside a diamond. Diamonds are forever – or, at least, the effects of this diamond on quantum computing may be. A team that includes scientists from USC has built a quantum computer in a diamond, the first of its kind to include protection against "decoherence" – noise that prevents the computer from functioning properly.
The demonstration shows the viability of solid-state quantum computers, which – unlike earlier gas- and liquid-state systems – may represent the future of quantum computing because they can be easily scaled up in size. Current quantum computers are typically very small and – though impressive – cannot yet compete with the speed of larger, traditional computers. The multinational team included USC Professor Daniel Lidar and USC postdoctoral researcher Zhihui Wang, as well as researchers from the Delft University of Technology in the Netherlands, Iowa State University and the University of California, Santa Barbara.
Their findings will be published on April 5 in Nature. Optical Device is More Than 100% Efficient. Physicists have known for decades that, in principle, a semiconductor device can emit more light power than it consumes electrically. Experiments published in Physical Review Letters finally demonstrate this in practice, though at a small scale. The energy absorbed by an electron as it traverses a light-emitting diode is equal to its charge times the applied voltage. But if the electron produces light, the emitted photon energy, which is determined by the semiconductor band gap, can be much larger.
Usually, however, most electrons create no photon, so the average light power is less than the electrical power consumed. Researchers aiming to increase the power efficiency have generally tried to boost the number of photons per electron. But Parthiban Santhanam and co-workers from the Massachusetts Institute of Technology in Cambridge took a gentler approach, achieving power enhancement even though less than one electron in a thousand produced a photon. Scenic Route for Sound Allows Extra Control. +Enlarge image Z. Liang and J. Li, Phys. Rev. Lett. (2012) Physicists have discovered surprising ways to manipulate the propagation of waves, notably light, by using structures assembled from tiny elements.
In Physical Review Letters, researchers propose to alter sound waves by diverting them through an array of narrow, circuitous channels, a method that wouldn’t work for light. For years, researchers have been changing the way electromagnetic radiation travels by engineering materials with internal structures on the scale of the wavelength. Researchers have recently extended these methods to acoustic waves. A sound wave (with wavelength larger than the squares) moving across the board gets delayed as it travels through the lengthy path within each square. The researchers confirmed with numerical simulations that a prism made of the metamaterial with a negative index of refraction bends sound in the opposite direction from ordinary refraction. –Don Monroe. Encoding many channels on the same frequency through radio vorticity: first experimental test.
Dome-shaped EUV Waves from Rotating Active Regions. Dark Matter Clump Furrows Brows: Scientific American Podcast. Dark matter. It’s hard to see, it’s hard to study and it just won’t behave. There’s plenty dark matter around. It’s just that no one knows what it is. It only makes its presence felt through its gravitational pull. But astronomers have figured out ways to ID dark matter. The problem was, the dark matter in A520 wasn’t where it ought to be. Why should dark matter behave so differently in different galaxy clusters? —John Matson [The above text is a transcript of this podcast.] A model burster.
For the first time, researchers at MIT and elsewhere have detected all phases of thermonuclear burning in a neutron star. The star, located close to the center of the galaxy in the globular cluster Terzan 5, is a “model burster,” says Manuel Linares, a postdoc at MIT’s Kavli Institute for Astrophysics and Space Research. Linares and his colleagues from MIT, McGill University, the University of Minnesota and the University of Amsterdam analyzed X-ray observations from NASA’s Rossi X-ray Timing Explorer (RXTE) satellite, and discovered the star is the first of its kind to burst the way that models predict. What’s more, the discovery may help explain why such a model star has not been detected until now. A paper to be published in the March 20 issue of The Astrophysical Journal details the group’s findings.
“These are extreme laboratories,” Linares says. A white-hot environment Neutron stars typically arise from the collapse of massive stars. Spikes in the data Turn, turn, turn. H.Res.550: Expressing the support of the House of Representatives for innovative transformative research... OpenCongress. What is causing the 'booms'? WILMINGTON, NC (WECT) - Something is shaking the southeast and has been for quite some time. Carolina Beach resident Jody Smith was enjoying a Saturday morning with her son Roman when she felt and heard a 'boom.' Her son walked to her and asked, "Mommy, what was that? " Smith didn't know how to respond. Many people in her neighborhood ran outside in hopes of finding the source of the noise. "It feels like a Mack truck driving by and it just shakes your whole house," said neighbor Paula Powell. "It's a shaking feeling," Smith added. Dozens posted on her wall and thousands have reported the noises up and down the coast on various websites from Georgia to Virginia.
"I don't think it's ghosts, and I don't think it's aliens," said Geophysicist Dr. For nearly 50 years, Hill has studied just that across the globe, publishing more than 75 papers. Hill said an earthquake produces audible sound by making the "ground around the person listening seem like they are in a big woofer. " Copyright 2011 WECT. New Super-Black Material Absorbs 99 Percent of All Light That Dares to Strike It. Staring at distant, faint objects to study the origins of the universe requires several layers of engineering skill and design trickery. The people at NASA are no strangers to this, having invented all sorts of new materials to improve telescopes and other observational tools.
A new design may be one of their best examples yet: A blacker-than-black nanomaterial that absorbs pretty much all of the light that hits it. The new material is made of carbon nanotubes and can be grown on a variety of space-friendly substrates, from silicon to titanium to stainless steel. This finely tuned fuligin absorbs an average 99 percent of all the ultraviolet, visible, infrared, and far-infrared light that hits it. It works by collecting and trapping light inside tiny gaps between the nanotubes, which are arranged in vertical fibrous strands like a tall shag carpet. This is much more efficient and effective than black paint, according to NASA. [NASA via PhysOrg] Longtime Playing with Electrostatics. Weird Science: Report your unusual phenomena. Elsevier boycott gathers pace. Timothy Gowers is surprised and delighted that thousands of mathematics and other researchers have joined him in a public pledge not to have anything to do with Elsevier, the Amsterdam-based academic publishing giant.
He is leading a boycott because of company practices that he says hinder the dissemination of research. But he is not expecting a big response from Elsevier. “The goal of the boycott is not to get Elsevier to change how it does things, but rather to change how we in the mathematics community behave, and in that way to rid ourselves of major commercial publishers,” he says. A boycott of Elsevier's high-impact journals, which include The Lancet, could have severe consequences for the company and researchers alike.
This won’t happen suddenly. “It may be necessary for things to go a bit quiet while we lay the ground work and put in some hard graft.” Widespread support Avoiding the company is unlikely to be problematic for mathematicians. Non-profit publishing. Book review of Rupert Sheldrake. In this book the British philosopher and biochemist Rupert Sheldrake put forth his controversial hypothesis of formative causation and morphogenetics. Sheldrake believes that the physical sciences will not solve the riddle of life because life is due to a holistic property that eludes the physical sciences. In particular, formative causation solves the problem of morphogenesis.
The foundation of Sheldrake's concept of formative causation is the idea that there is a memory inherent in nature (an idea borrowed from the nineteenth century biologist Samuel Butler). Then memory expresses itself through "morphic fields". Morphogenetic fields carry information only (no energy) and are available throughout time and space. Morphic resonance is the process by which the form of a system is influenced by the forms of past similar systems through the morphogenetic field.
For example, genes do not carry all the information needed to shape an organism. The Structure of the Physical Universe, Chapter XXVIII. The Structure of the Physical Universe: Chapter XXV. The Nobel Prize-Winning Discovery that Got a Scientist Kicked Out of His Own Lab. Mad science News, Videos, Reviews and Gossip - io9. Mad science News, Videos, Reviews and Gossip - io9. High speed video reveals the bizarre physics of an ordinary water droplet - StumbleUpon.