Mathematics & Physics articles

A mathematical solution for another dimension
Ever since 1887, when Norwegian mathematician Sophus Lie discovered the mathematical group called E8, researchers have been trying to understand the extraordinarily complex object described by a numerical matrix of more than 400,000 rows and columns.

Scientists develop new terahertz material
Researchers at Los Alamos National Laboratory have created a device for manipulating terahertz (THz) radiation. The device could be the basis for novel electronics and photonics applications ranging from new imaging methods to advanced communication technologies. The THz range of the electromagnetic spectrum lies between the infrared and microwave wavelengths.

Harnessing new frequencies
Modern technology uses many frequencies of electromagnetic radiation for communication, including radio waves, TV signals, microwaves and visible light. Now, a University of Utah study shows how far-infrared light – the last unexploited part of the electromagnetic spectrum – could be harnessed to build much faster wireless communications and to detect concealed explosives and biological weapons.

Physicists shine a light, produce startling liquid jet
It is possible to manipulate small quantities of liquid using only the force of light, report University of Chicago and French scientists in the March 30 issue of Physical Review Letters.

'Smart' sunglasses and goggles let users adjust shade and color
Imagine a single pair of glasses with lenses that can be transparent or dark, and in shades of yellow, green or purple, all on command. A new lens with chameleon powers promises to dramatically improve sunglasses' function.

Negative refraction of visible light demonstrated; could lead to cloaking devices
For the first time, physicists have devised a way to make visible light travel in the opposite direction that it normally bends when passing from one material to another, like from air through water or glass. The phenomenon is known as negative refraction and could in principle be used to construct optical microscopes for imaging things as small as molecules, and even to create cloaking devices for rendering objects invisible.

Laser goes tubing for faster body-fluid tests
University of Rochester researchers announce in the current issue of Applied Optics a technique that in 60 seconds or less measures multiple chemicals in body fluids, using a laser, white light, and a reflective tube. The technique tests urine and blood serum for common chemicals important to monitoring and treatment of diabetes and cardiovascular, kidney, urinary and other diseases, and lends itself to the development of fast batch testing in hospitals and other clinical settings.

Laser-cooling brings large object near absolute zero
Using a laser-cooling technique that could one day allow scientists to observe quantum behavior in large objects, MIT researchers have cooled a coin-sized object to within one degree of absolute zero.

For the first time the lhc reaches temperatures colder than outer space
The first sector of CERN's Large Hadron Collider (LHC) to be cooled down has reached a temperature of 1.9 K (-271°C), colder than deep outer space!

Electrons caught in the act of tunnelling
We have to climb a mountain in order to conquer it. In quantum physics there is a different way: objects can reach the opposite side of a hill simply by tunnelling through it, instead of laboriously climbing over it. An international team of researchers working with Prof. Ferenc Krausz from the Max Planck Institute for Quantum Optics has now observed electrons in this tunnelling process.

Revamped experiment could detect elusive particle
An experiment called "shining light through walls" would seem hard to improve upon. But University of Florida physicists have proposed a way to do just that, a step they say considerably improves the chance of detecting one of the universe's most elusive particles, a candidate for the common but mysterious dark matter.

Water flows like molasses on the nanoscale
A Georgia Tech research team has discovered that water exhibits very different properties when it is confined to channels less than two nanometers wide – behaving much like a viscous fluid with a viscosity approaching that of molasses. Determining the properties of water on the nanoscale may prove important for biological and pharmaceutical research as well as nanotechnology. The research appears in the March 15 issue of the journal Physical Review B.

Segment of a quantum repeater demonstrated
Physicists at the California Institute of Technology have succeeded for the first time in the distribution of "entanglement" in a way that could lead to long-distance quantum communications, scalable quantum networks, and even a quantum internet.

Ultrashort light pulse blazes new paths for science, industry
Researchers in Italy have created an ultrashort light pulse—a single isolated burst of extreme-ultraviolet light that lasts for only 130 attoseconds (billionths of a billionth of a second). Their achievement currently represents the shortest artificial light pulse that has been reported in a refereed journal.

Laser-trapping of rare element gets unexpected assist
Argonne researchers have successfully laser-cooled and trapped atoms of radium — the first time this rare element has been captured in a magneto-optical trap — with an assist from an unexpected source.

Princeton physicists connect string theory with established physics
String theory, simultaneously one of the most promising and controversial ideas in modern physics, may be more capable of helping probe the inner workings of subatomic particles than was previously thought, according to a team of Princeton University scientists.

Quasicrystals: somewhere between order and disorder
Professionally speaking, things in David Damanik's world don't line up – and he can prove it.

Making plasmas in the deepest of deep freezes
Rice University physicist Tom Killian is one of a growing group of researchers worldwide who are unlocking some of the mysteries of plasmas by doing something nature never does -- freezing them to less than a degree above absolute zero.

UCR physicist demonstrates how light can be used to remotely operate micromachines
A research team led by Umar Mohideen, a physicist at the University of California, Riverside, has demonstrated in the laboratory that the Casimir force – the small attractive force that acts between two close parallel uncharged conducting plates – can be changed using a beam of light, making the remote operation of micromachines a possibility.

When atoms collide
Scientists at the UK's National Physical Laboratory (NPL) have proposed a new way to determine accurate time faster.