Mathematics & Physics articles

Magnetism flicks switch on 'dark excitons'
In new experimental research appearing in Physical Review Letters, a Rice University-led team of nanoscientists and electrical engineers has flipped the switch on 'dark excitons' in carbon nanotubes by placing them inside a strong magnetic field.

Researchers find new source of coherent light
With the exception of lasers and free-electron lasers, there hasn't been another fundamental way to produce coherent light for close to 50 years. But a group of researchers from Lawrence Livermore National Laboratory and the Massachusetts Institute of Technology have found a new source of coherent optical radiation that is distinct from lasers and free-electron lasers.

Scientists stretch carbon nanotubes
Physicists at Boston College have for the first time shown that carbon nanotubes can be stretched at high temperature to nearly four times their original length, a finding that could have implications for future semiconductor design as well as in the development of new nanocomposites.

Indigenous amazonians display core understanding of geometry
Researchers in France and at Harvard University have found that isolated indigenous peoples deep in the Amazon readily grasp basic concepts of geometry such as points, lines, parallelism and right angles, and can use distance, angle and other relationships in maps to locate hidden objects. The results suggest that geometry is a core set of intuitions present in all humans, regardless of their language or schooling.

Toward a quantum computer, one dot at a time
Researchers at the University of Pittsburgh have developed a way to create semiconductor islands smaller than 10 nanometers in scale, known as quantum dots. The islands, made from germanium and placed on the surface of silicon with two-nanometer precision, are capable of confining single electrons.

New theory explains electronic and thermal behavior of nanotubes
Researchers at the University of Illinois at Urbana-Champaign have made an important theoretical breakthrough in the understanding of energy dissipation and thermal breakdown in metallic carbon nanotubes. Their discovery will help move nanotube wires from laboratory to marketplace.

South pole detector could yield signs of extra dimensions
Researchers at Northeastern University and the University of California, Irvine say that scientists might soon have evidence for extra dimensions and other exotic predictions of string theory. Early results from a neutrino detector at the South Pole, called AMANDA, show that ghostlike particles from space could serve as probes to a world beyond our familiar three dimensions, the research team says.

Less sunlight, but temps rise
Less sunlight reaching the Earth's surface has not translated into cooler temperatures, according to a team of solar physicists at New Jersey Institute of Technology (NJIT). The scientists, who monitor the Earth's reflectance by measuring what is known as the moon's earthshine, have observed that the amount of light reflected by Earth -- its albedo -- has increased since 2000. The result has been less sunlight reaching the Earth's surface.

Researchers shed new light on the physical properties of carbon
A team based in Livermore has shed some new light on the phase diagram of carbon at high pressure and temperature.

DNA-wrapped carbon nanotubes serve as sensors in living cells
Single-walled carbon nanotubes wrapped with DNA can be placed inside living cells and detect trace amounts of harmful contaminants using near infrared light, report researchers at the University of Illinois at Urbana-Champaign. Their discovery opens the door to new types of optical sensors and biomarkers that exploit the unique properties of nanoparticles in living systems.

New sonofusion experiment produces results without external neutron source
A team of researchers from Rensselaer Polytechnic Institute, Purdue University, and the Russian Academy of Sciences has used sound waves to induce nuclear fusion without the need for an external neutron source, according to a paper in the Jan. 27 issue of Physical Review Letters.

A NEW MATHEMATICAL METHOD PROVIDES A BETTER WAY TO ANALYZE NOISE
Humans have 200 million light receptors in their eyes, 10 to 20 million receptors devoted to smell, but only 8,000 dedicated to sound.

What can a magnet tell you about rain patterns? more than you would guess
If someone said you can understand rain patterns and the dynamics of the atmosphere by studying magnets and magnetism

G-Zero update
In research performed in Hall C, nuclear physicists have found that strange quarks do contribute to the structure of the proton.

What do Racquel Welch and quantum physics have in common?
Recent investment by the University of Leicester in the Virtual Microscopy Centre and the Nanoscale Interfaces Centre has put the University in a key position to take a lead in Casimir force measurements in novel geometries

Variable phisical laws
: Physical quantities such as the speed of light, the gravitational constant and the electron mass are believed to be the same independent of where and when they appear in the universe

Researchers discover how to focus on tiniest of the very small
If you need a good picture of a molecule, your first job is getting its atoms to pose for you, says John Silcox, Cornell's David E. Burr Professor of Engineering and an expert in the realm of the very tiny

Scientists resolve 60-year-old plutonium questions
Scientists have solved a question about the nature of plutonium that had remained a mystery since the Manhattan Project.

Through a glass clearly
Glass may seem to us to be one of nature's most transparent creations, but when it comes to its atomic structure it is a dark world of which little is known

Researchers create new organic gel nanomaterials
Researchers have created organic gel nanomaterials that could be used to encapsulate pharmaceutical, food, and cosmetic products and to build 3-D biological scaffolds for tissue engineering