Relativistic trading: The speed of light isn't fast enough for some market transactions

The profit made on a stock share bought and sold a moment later might only be a penny or so, but if multiplied by millions of shares over the course of a day the money earned can be big.

Holometer experiment to test if the universe is a hologram

Many ideas in theoretical physics involve extra dimensions, but the possibility that the universe has only two dimensions could also have surprising implications. The idea is that space on the ultra-small Planck scale is two-dimensional, and the third dimension is inextricably linked with time. If this is the case, then our three-dimensional universe is nothing more than a hologram of a two-dimensional universe.

Topological insulators could help define fundamental constants

A newly discovered class of materials known as "topological insulators" could help physicists to obtain new ways of defining the three basic physical constants – the speed of light (c); the charge of the proton (e); and Planck’s constant (h). That’s the claim of a team of physicists in the US, which has proposed a new experiment to measure the fine-structure constant (α), which is a function of h, c and e, by scattering light from such a material. Topological insulators are unusual in that electrical current flows well on their surface, but not through their bulk.

The quest for dilute ferromagnetism in semiconductors: Guides and misguides by theory

A material that exhibits both ferromagnetic and semiconductor properties offers the exciting prospect of combining nonvolatile magnetic storage and conventional semiconductor electronics in a single device. Magnetic semiconductors offer a number of interesting possibilities in the pursuit of  spintronics , a branch of science and technology that exploits the spin dimension of the electron in addition to its charge, for novel electronic devices. These materials combine the properties of a semiconductor and a magnetic material, providing, for instance, a way to create 100 % spin-polarized currents, and by the same token, the promise of electrical control of magnetic effects. While in some magnetic semiconductors, for example, magnetite, all of the material’s constituent ions are intrinsically magnetic (  concentrated magnets  ), the most recent focus has been on nonmagnetic semiconductor host materials that can be doped by a small amount of magnetic transition-metal ions or by defects that promote magnetism (  dilute magnets  ).

Understanding behavioural patterns: why bird flocks move in unison

Animal flocks, be it honeybees, fish, ants or birds, often move in surprising synchronicity and seemingly make unanimous decisions at a moment’s notice, a phenomenon which has remained puzzling to many researchers.

New research published today in the New Journal of Physics ( co-owned by the Institute of Physics and German Physical Society ), uses a particle model to explain the collective decision making process of flocks of birds landing on foraging flights.

Using a simple self-propelled particle (SPP) system, which sees the birds represented by particles with such parameters as position and velocity, the researchers from Budapest, Hungary, find that the collective switching from the flying to the landing state overrides the individual landing intentions of each bird.

Relativity with a human touch

In the famous twin paradox, a sibling who journeys in a fast-moving spacecraft will return home younger than the sibling who remained on Earth. While this apparent slowing of time occurs whenever a body is set in motion, it had been much too small to be detected for movement on a human scale.

Who wants to live for ever? A scientific breakthrough could mean humans live for hundreds of years

A genetically engineered organism that lives 10 times longer than normal has been created by scientists in California. It is the greatest extension of longevity yet achieved by researchers investigating the scientific nature of ageing.

Einstein's theory is proved – and it is bad news if you own a penthouse

The world's most accurate clock has neatly shown how right Albert Einstein was 100 years ago, when he proposed that time is a relative concept and the higher you live above sea level the faster you should age.

Quantum Time Machine Lets You Travel to the Past Without Fear of Grandfather Paradox

Looking to build a time machine but nervous about the classic grandfather paradox, aka the Marty McFly conundrum, aka the idea that you might unwittingly do something that causes you to never exist in the first place? An MIT professor and a few of his quantum quoting buddies have published a theory that  allows for time travel while circumventing the grandfather paradox . All you need is a quantum teleportation device and a precise understanding of the idea of postselection--Flux Capacitor optional.

Topological insulators: Star material

 A topological insulator sounds simple enough:  A block of material that lets electrons move along its surface, but not through its inside . In fact, it is far from straightforward. Ordinary metals conduct electrons all the way through, whereas ordinary insulators don't conduct electrons at all. A copper-plated block of wood conducts only on the surface, but that is two materials, not one. The idea of a topological insulator is so strange that for a long time, physicists had no reason to believe that such a material would exist .

 Researchers also believe that the collective motions of electrons inside topological insulators will mimic several of the never-before-seen particles predicted by high-energy physicists. Among them are axions, hypothetical particles predicted in the 1970s; magnetic monopoles, single points of north and south magnetism; and Majorana particles — massless, chargeless entities that can serve as their own antiparticles. 

Could some entangled states be useless for quantum cryptography ?

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One of the widely accepted properties of quantum entanglement is secrecy. Since scientists and researchers began working with quantum key distribution, entanglement has been considered an essential part of keeping communications private. What if entanglement didn't always mean secrecy, though ? New work is shedding light on the nature of entanglement and quantum key distribution -  and possibly proving that a high degree of entanglement does not necessarily lead to complete secrecy .

What Is Time? One Physicist Hunts for the Ultimate Theory

One way to get noticed as a scientist is to tackle a really difficult problem. Physicist Sean Carroll has become a bit of a rock star in geek circles by attempting to answer an age-old question no scientist has been able to fully explain: What is time ?.

Dropping ultra-cold quantum gas down an elevator shaft could help prove Einstein wrong

Scientists have shown that it’s possible to keep sufficiently close tabs on quantum mechanical objects in free fall to tell whether two such objects experience gravity the same way. In 1907, Einstein suggested that if you were in a windowless elevator that was plunging towards Earth in free fall, you would feel the same weightlessness as if you were floating in outer space. This notion, known as the equivalence principle, laid the foundation for general relativity. It explains why a pebble and a piano fall at the same speed if dropped from the same roof, despite their different masses. It’s also a necessary first step toward describing the effects of gravity as curvature in spacetime.

Read More http://www.wired.com/wiredscience/2010/06/quantum-gravity-in-an-elevator/#ixzz0rBEhUpVj

Stretched molecule puts a new spin on electrons

Physicists in the US have invented a way of measuring the magnetic properties of a single molecule as it is being stretched. The technique provides a

new approach for studying quantum chemistry and how the spin of an electron affects its passage through tiny structures.

The technique could one day even be adapted for use in spintronic devices, which use the spin of the electron to process and store information.

Physicists build quantum amplifier with single artificial atom

By demonstrating how a single artificial atom can be used to amplify electromagnetic waves, physicists from Japan are opening up new possibilities for quantum amplifiers, which can be used in a variety of electronic and optical applications.

Entropy study suggests Pictish symbols likely were part of a written language

How can you tell the difference between random pictures and an ancient, symbol-based language ?

 A new study has shown that concepts in entropy can be used to measure the degree of repetitiveness in Pictish symbols from the Dark Ages, with the results suggesting that the inscriptions appear be much closer to a modern written language than to random symbols 

. The Picts, a group of Celtic tribes that lived in Scotland from around the 4th-9th centuries AD, left behind only a few hundred stones expertly carved with symbols. Although the symbols appear to convey information, it has so far been impossible to prove that this small sample of symbols represents a written language.

Physicsts reveal how to cope with 'frustration'

For most people, frustration is a condition to be avoided. But for scientists studying certain "frustrated" ensembles of interacting components -that is, those which cannot settle into a state that minimizes each interaction-

 it may be the key to understanding a host of puzzling phenomena that affect systems from neural networks and social structures to protein folding and magnetism.

Math behind Internet encryption wins top award: Abel prize awarded to number theorist John Tate

The Abel prize--considered the "Nobel" prize of mathematics--has been awarded to John Tate, recently retired from the University of Texas at Austin, for his work on algebraic number theory, the mathematical discipline that deals with connections between whole numbers and lies at the heart of Internet security.
Established in 2002, the Abel Prize is presented annually by the King of Norway and carries a cash award of $1 million.

Ian Stewart:  Try to find the prime factors of a 200-digit number with pencil and paper--or even with a computer program--and it would take longer than the age of the Universe .

John Tate Biography in Wikipedia

Electrical properties of glass at the nanoscale lead to a pump the size of a red blood cell

Researchers have devised a way to fabricate tiny electrodes from glass, harnessing a phenomenon by which nanoscale glass walls can be transformed from insulators to conductors and back again. At larger scales, that phenomenon, known as  dielectric breakdown , leads to excess heating and structural damage,  but at the nanoscale the process appears to be harmless and  reversible.

Vitaly Lazarevich Ginzburg

Vitaly Lazarevich Ginzburg, who made important contributions in many fields of theoretical physics, passed away on 8 November 2009 in Moscow; he had suffered for several years from a blood disease.