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Laser Crosswalk Saves Pedestrians From a Painful Death

Laser Crosswalk Saves Pedestrians From a Painful Death
When the light turns red, a huge laser wall projecting apparitions of crossing pedestrians spans across the crosswalk. The concept is designed to keep crossing pedestrians safe from any overzealous drivers who otherwise might have ran the red light. Link [via] Related:  Physics

Coriolis-like effect found 184 years before Coriolis - physics-math - 14 January 2011 The cosmos loves irony. While trying to prove that the Earth is fixed in space, an Italian priest described something similar to the Coriolis effect – the slight deflection experienced by objects moving in a rotating frame of reference – nearly 200 years before mathematician Gustave Coriolis worked it out in 1835. In 1651, Giovanni Riccioli published 77 arguments against the idea that the apparent motions of the heavens were due to the Earth's rotation and orbit around the sun. These included claims that Hell would be in the wrong place, aesthetic concerns over proportion and harmony, and more scientific approaches. Now, Christopher Graney at Jefferson Community and Technical College in Louisville, Kentucky, has translated them from Latin, and discovered that Riccioli conjectured phenomena resembling the Coriolis effect (arxiv.org/abs/1012.3642). In reality, the Coriolis effect is subtle, noticeable mainly in large-scale systems such as weather patterns and ocean currents. (YouTube)

Scientists discover snowflake identical to one which fell in 1963 Scientists were today able to dispel the age-old belief that no two snowflakes are the same, using state of the art microscopy and by catching flakes as they fell in specially designed equipment while sitting at a table outside a pub in Norwich. The team of researchers, backed by a £20m grant, were able to make an identical match to the famous Bentley flake, photographed 47 years ago by amateur snowflakeologist Wilson Bentley. ‘It’s one of the last remaining challenges known to science and we’ve cracked it at last,’ said lead researcher, Professor Kenneth Libbrecht. ‘The team will soon disband to pursue other major scientific challenges, such as the unresolved toast-butter conundrum, and whether or not my baldness makes me a better lover.’ The scientists then ordered another round and considered the futility of existence, an activity for which they also receive a grant worth twice the GDP of Tonga. Picture by larryharry Click to send this story to a friend

CERN: Light Speed May Have Been Exceeded By Subatomic Particle GENEVA — One of the very pillars of physics and Einstein's theory of relativity – that nothing can go faster than the speed of light – was rocked Thursday by new findings from one of the world's foremost laboratories. European researchers said they clocked an oddball type of subatomic particle called a neutrino going faster than the 186,282 miles per second that has long been considered the cosmic speed limit. The claim was met with skepticism, with one outside physicist calling it the equivalent of saying you have a flying carpet. "The feeling that most people have is this can't be right, this can't be real," said James Gillies, a spokesman for the European Organization for Nuclear Research, or CERN, which provided the particle accelerator that sent neutrinos on their breakneck 454-mile trip underground from Geneva to Italy. Stephen Parke, who is head theoretician at the Fermilab near Chicago and was not part of the research, said: "It's a shock. Borenstein reported from Washington.

9 Things You Didn't Know About Benjamin Franklin It's Fun Friday -- time for some fun for the weekend. Enjoy today's post and I'll see you back here on Monday with more philatelic news and notes. United States, 1938Scott #803 In 1938, the United States issued a set of definitive postage stamps featuring images of the nation's first 29 presidents. This issue has affectionately become known as the Prexies issue. In addition to the 29 presidents featured on the stamps, fractional postage stamps were issued with images of non-presidents, such as Benjamin Franklin and Martha Washington, and the White House. For those not familiar with fractional postage, some types of U.S. mail required a partial cent, even though there was no coinage for half cents in use in the United States at the time. The first stamp (in denomination order) is the half-cent Benjamin Franklin issue. He never once sought public office. Previous Fun Friday Posts

World’s Most Precise Clocks Could Reveal Universe Is a Hologram | Wired Science Our existence could be coded in a finite bandwidth, like a live ultra-high-definition 3-D video. And the third dimension we know and love could be no more than a holographic projection of a 2-D surface. A scientist’s $1 million experiment, now under construction in Illinois, will attempt to test these ideas by the end of next year using what will be two of the world’s most precise clocks. Skeptics of a positive result abound, but their caution comes with good reason: The smallest pieces of space, time, mass and other properties of the universe, called Planck units, are so tiny that verifying them by experiment may be impossible. The Planck unit of length, for example, is 10 billion billion times smaller than the width of a proton. Craig Hogan, a particle astrophysicist at Fermilab in Illinois, isn’t letting this seemingly insurmountable barrier stop him from trying. Hogan is following through on a radical idea to confirm Planck units with two of the most precise clocks in the world.

Quantum Computing: Will It Be a Leap in Human Evolution? Quantum computers have the potential to solve problems that would take a classical computer longer than the age of the universe. Oxford Professor David Deutsch, quantum-computing pioneer, who wrote in his controversial masterpiece, Fabric of Reality says: "quantum computers can efficiently render every physically possible quantum environment, even when vast numbers of universes are interacting. Quantum computers can also efficiently solve certain mathematical problems, such as factorization, which are classically intractable, and can implement types of cryptography which are classically impossible. Quantum computation is a qualitatively new way of harnessing nature." Quantum computing sounds like science fiction -as satellites, moon shots, and the original microprocessor once were. To leapfrog the silicon wall, we have to figure out how to manipulate the brain-bending rules of the quantum realm - an Alice in Wonderland world of subatomic particles that can be in two places at once.

Laws of physics vary throughout the universe, new study suggests A team of astrophysicists based in Australia and England has uncovered evidence that the laws of physics are different in different parts of the universe. The team -- from the University of New South Wales, Swinburne University of Technology and the University of Cambridge -- has submitted a report of the discovery for publication in the journal Physical Review Letters. A preliminary version of the paper is currently under peer review. The report describes how one of the supposed fundamental constants of Nature appears not to be constant after all. Instead, this 'magic number' known as the fine-structure constant -- 'alpha' for short -- appears to vary throughout the universe. "The implications for our current understanding of science are profound. "If our results are correct, clearly we shall need new physical theories to satisfactorily describe them." The discovery will force scientists to rethink their understanding of Nature's laws.

Serious Flaw Emerges In Quantum Cryptography The problem of sending messages securely has troubled humankind since the dawn of civilisation and probably before. In recent years, however, physicists have raised expectations that this problem has been solved by the invention of quantum key distribution. This exploits the strange quantum property of entanglement to guarantee the secrecy of a message. Entanglement is so fragile that any eavesdropper cannot help but break it, revealing the ruse. So cryptographers can use it to send a secure key called a one time pad that can then be used to encrypt a message. If the key is intercepted, the sender simply sends another and repeats this until one gets through. So-called quantum key distribution is unconditionally secure–it offers perfect secrecy guaranteed by the laws of physics. Or at least that’s what everyone thought. For example, lasers that are supposed to send one photon at a time can sometimes send several and this allows information to leak to an eavesdropper. Here’s the problem.

Arranca la búsqueda de la 'partícula Dios' La sala de reuniones del partido tory está llena de militantes que charlan tranquilamente cuando, de pronto, la señora Thatcher entra por la puerta. A medida que Thatcher camina por la habitación, los militantes más cercanos forman corrillos a su alrededor y, en consecuencia, dificultan el movimiento de su líder. Los militantes representan el campo de Higgs, una forma de energía que impregna todo el espacio y confiere masa a las partículas (como Thatcher). La anterior parábola, debida al físico británico David Miller, es un pequeño clásico de la divulgación científica. Sin el misterioso campo de Higgs seríamos livianos como el fotón Para observar la partícula elemental se requieren altas energías de colisión Incluso si se crean miniagujeros negros, no serían peligrosos Falta una teoría que explique las grandes fuerzas de la naturaleza El campo de Higgs y el bosón de Higgs son dos formas de ver el mismo fenómeno. Weinberg, Salam y Glashow recibieron el premio Nobel en 1979.

Una nueva partícula, quizás el bosón de Higgs, se filtra antes de tiempo "Hemos observado una nueva partícula... Tenemos fuerte evidencia de que hay algo ahí", dice Joe Incandela, el portavoz de CMS, uno de los grandes detectores del acelerador de partículas LHC, en un vídeo que se ha hecho público, seguramente por error, antes de tiempo, ya que se ha retirado inmediatamente del acceso público, según ha informado Science News. La presentación de los últimos datos del LHC, que se espera que signifiquen el descubrimiento de la muy buscada partícula de Higgs, o el casi descubrimiento, está prevista para este miércoles por la mañana en el Laboratorio Europeo de Física de Partículas (CERN), junto a Ginebra. "El vídeo es uno de los varios que se han preparado para cubrir diferentes posibles escenarios de un anuncio del Higgs, y no debía haber sido publicado online", ha declarado una portavoz de la oficina de prensa del CERN.

New kind of light created in physics breakthrough Physicists have created a new kind of light by chilling photons into a blob state. Just like solids, liquids and gases, this recently discovered condition represents a state of matter. Called a Bose-Einstein condensate, it was created in 1995 with super-cold atoms of a gas, but scientists had thought it could not be done with photons, which are basic units of light. However, physicists Jan Klärs, Julian Schmitt, Frank Vewinger and Martin Weitz of the University of Bonn in Germany reported accomplishing it. They have dubbed the new particles "super photons." Particles in a traditional Bose-Einstein condensate are cooled down close to absolute zero, until they glom onto each other and become indistinguishable, acting as one giant particle. The scientists needed to find a way to cool the photons without decreasing their numbers. "Many scientists believed that it would not be possible, but I was pretty sure that it would work," Weitz told LiveScience. Related on LiveScience:

Stuff under an electron microscope Science Normal things become surreal when put under an electron microscope. Used dental floss Mascara brush Salt and pepper Stamp Used cotton swab Needle and thread Parts of a computer chip Electric razor with hair Guitar string Velcro Lighter Toilet paper The inside of a pencil Tooth brush

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