Figure 1: By coupling a nonlinear system, such as an atom, to the electromagnetic field, it is possible to create Fock states (eigenstates of the harmonic oscillator). (Top) Brune et al. send atoms (left) into a cavity (center). The atoms are prepared with pulse P1 to be in a superposition of states |e〉 and |g〉 before they enter the cavity. The relative phase between these states, which is converted to probability amplitudes for |e〉 and |g〉 with pulse P2 when the atoms exit the cavity, depend... Read Full Story

Figure 1: (a) A classical system of Brownian spheres may crystallize at low temperatures if cooled slowly. By contrast, a bi-disperse system (i.e., consisting of two different kinds of hard spheres) such as the one shown cannot crystallize and will jam into a glass at high densities and low temperatures. Similarly, a rapidly cooled system of hard spheres does not have enough “time” to crystallize and forms a glass instead. Using the mapping of [7], it is seen that the quantum analog of the cl... Read Full Story

Figure 1: (Top) The bifurcation and stability diagram for rotating liquid drops that are held together by surface tension. The plot depicts dimensionless angular velocity as a function of dimensionless angular momentum. The depicted shapes are stable along the solid lines and unstable along the dashed lines. All shapes with more than 2 lobes are unstable. (Bottom) The experimental setup used by Hill and Eaves. The water droplet is suspended by a magnetic field. The field also exerts a torque ... Read Full Story

Figure 1: A magnetoelectric effect in a topological insulator. (Left) A quantum Hall effect occurs without strong magnetic field when an electric field applied in the plane of the interface between a topological (red region) and an ordinary (blue region) insulator (or vacuum) induces a precisely quantized current perpendicular to the field. (Right) A magnetic field applied perpendicular to the same interface introduces (n+1/2) electrons for each flux quantum of applied field. The shaded regio... Read Full Story

Billions of anti-matter particles were recently let loose at Lawrence Livermore National Laboratory. Using a short-pulse laser, a team of researchers figured out how to produce anti-electrons or positrons faster and in greater density than ever before in the laboratory.While positrons were the only form of anti-matter produced in the experiment, not all anti-matter particles are positrons. Every particle has its own corresponding, oppositely charged anti-particle (check out last month's p... Read Full Story

I'd wager the average person rarely (if ever), spends a Friday evening indulging in Die Meistersinger von Nurnberg, but operas aren't always long-winded scenes of voluptuous, ornately dressed characters bellowing incomprehensibly.Producer John Adam's Doctor Atomic is a two-act opera about the making of the Atom Bomb, the nuclear weapon that was eventually dropped on Hiroshima and Nagasaki near the end of World War II.The setting is the summer of 1945, in the desert of Los Alamos, ... Read Full Story

Remember Gray's paradox? In 1936 the eponymous British zoologist James Gray couldn't reconcile his observations of dolphins swimming at speeds of over 20 miles per hour with his calculations, which demonstrated that dolphin muscles simply weren't built to produce enough acceleration to overcome drag. He ended up blaming this drag violation on dolphin's skin, postulating that it must have drag-reducing properties.Fast forward decades later to this year's Annual Meeting of t... Read Full Story

Anyone who’s ever tried to defend a sand castle against the onslaught of a rising tide will have some notion of the enormous energy carried by the waves crashing onto our shores. It has been estimated that wave power could supply a quarter of UK energy demand, yet converting it into electricity is more difficult than it looks. Current research efforts have branched out into many directions, each seeking to tame the ocean into an efficient commercially viable energy source. One such approach i... Read Full Story

What will be in astronauts' lunch boxes when they go to Mars? Soggy sandwiches, squishy bananas and crisps are unlikely to make the cut.‘If we go to Mars, that’s a two and a half year mission, so the food would need a five year shelf life,’ explains Dr Michele Perchonok, a food scientist at NASA’s Johnson Space Center in Houston. There is no refrigeration on board spaceships, so harmful bacteria will have to be zapped before take-off using high pressure processing or microwave sterilisati... Read Full Story

Physics is more quantitative than most other sciences. That is, many of the observations experimental results in physics are numerical measurements. Most of the theories in physics use mathematics to express their principles. Most of the predictions from these theories are numerical. This is because of the areas which physics has addressed are more amenable to quantitative approaches than other areas. Physical definitions, models and theories can often be expressed using mathematical relation... Read Full Story