Mathematics & Physics articlesPhysicists create new form of matter
MIT scientists have brought a supercool end to a heated race among physicists: They have become the first to create a new type of matter, a gas of atoms that shows high-temperature superfluidity.
Can an electron be in two places at the same time?
In something akin to a double-slit experiment, scientists at the Fritz Haber Institute of the Max Planck Society, in co-operation with researchers from the California Institute of Technology in Pasadena, California, have shown for the first time that electrons have characteristics of both waves and particles at the same time and in virtually the push of a button can be switched back and forth between these states.
Light that travels… faster than light!
A team of researchers from the Ecole Polytechnique Fédérale de Lausanne (EPFL) has successfully demonstrated, for the first time, that it is possible to control the speed of light – both slowing it down and speeding it up – in an optical fiber, using off-the-shelf instrumentation in normal environmental conditions.
New mechanism for metallic magnetism
Predicting the magnetic behavior of metallic compounds is a surprisingly difficult problem for theoretical physicists. While the properties of a common refrigerator magnet are not a great mystery, certain materials exhibit magnetic properties that do not fit within existing theories of magnetism. One such material inspired a recent theoretical breakthrough by physicists at the University of California, Santa Cruz.
Of friction and 'The Da Vinci Code'
The Da Vinci Code, the best selling novel and soon-to-be-blockbuster film, may also be linked some day to the solving of a scientific mystery as old as Leonardo Da Vinci himself — friction.
Research sheds light on ancient mystery
A researcher at Rochester Institute of Technology is unraveling a mystery surrounding Easter Island. William Basener, assistant professor of mathematics, has created the first mathematical formula to accurately model the island's monumental societal collapse.
Algorithm for learning languages
Cornell University and Tel Aviv University researchers have developed a method for enabling a computer program to scan text in any of a number of languages, including English and Chinese, and autonomously and without previous information infer the underlying rules of grammar. The rules can then be used to generate new and meaningful sentences. The method also works for such data as sheet music or protein sequences.
Scientists gain new insight into nanoscale optics
New research from Rice University has demonstrated an important analogy between electronics and optics that will enable light waves to be coupled efficiently to nanoscale structures and devices.
Physicists measure tiny force that limits how far machines can shrink
University of Arizona physicists have directly measured how close speeding atoms can come to a surface before the atoms' wavelengths change.
Math unites the celestial and the atomic
In recent years, researchers have developed astonishing new insights into a hidden unity between the motion of objects in space and that of the smallest particles. It turns out there is an almost perfect parallel between the mathematics describing celestial mechanics and the mathematics governing some aspects of atomic physics.
Universe evolution favored three and seven dimensions
Physicists who work with a concept called string theory envision our universe as an eerie place with at least nine spatial dimensions, six of them hidden from us, perhaps curled up in some way so they are undetectable. The big question is why we experience the universe in only three spatial dimensions instead of four, or six, or nine.
Presto! It's a semiconductor
Researchers at the University of Pennsylvania may not have turned lead into gold as alchemists once sought to do, but they did turn lead and selenium nanocrystals into solids with remarkable physical properties. In the October 5 edition of Physical Review Letters, online now, physicists Hugo E. Romero and Marija Drndic describe how they developed am artificial solid that can be transformed from an insulator to a semiconductor.
Brownian motion under the microscope
An international group of researchers from the EPFL (Ecole Polytechnique Fédérale de Lausanne), the University of Texas at Austin and the European Molecular Biology Laboratory in Heidelberg, Germany have demonstrated that Brownian motion of a single particle behaves differently than Einstein postulated one century ago.
New equation helps unravel behavior of turbulence
To most people, turbulence is the jolt felt by jet passengers moving through a rough pocket of air. But to scientists, turbulence is the chaotic flow of a gas or liquid, in which parts of the current curl into irregular, ever smaller, tight eddies.
Ultrafast lasers take 'snapshots' as atoms collide
Using laser pulses that last just 70 femtoseconds (quadrillionths of a second), physicists have observed in greater detail than ever before what happens when atoms collide.
Why 'filling-it-up' takes more than 'tank capacity'
You fill up your "empty" fuel tank at the gas station and the pump charges you for more gallons than the tank's rated capacity. Are you being deliberately overcharged?
New approach to studying antimatter
What happens when two atoms, each made up of an electron and its antimatter counterpart, called the positron, collide with each other? UC Riverside physicists are able to see for the first time in the laboratory that these atoms, which are called positronium atoms and are unstable by nature, become even more unstable after the collision. The positronium atoms are seen to destroy one another, turning into gamma radiation, a powerful type of electromagnetic radiation.
Lightning research sparks new discovery
Lightning, a high-voltage discharge that strikes quickly and sometimes fatally, is very difficult to study. A new and surprising finding by Florida Institute of Technology's Dr. Joseph Dwyer and his team brings the study of lightning research into the laboratory.
What does 'almost nothing' weight?
If subatomic particles had personalities, neutrinos would be the ultimate wallflowers. One of the most basic particles of matter in the universe, they've been around for 14 billion years and permeate every inch of space, but they're so inconceivably tiny that they've been called "almost nothing" and pass straight through things without a bump.
Mathematics: the loss of certainty
"Pure mathematics will remain more reliable than most other forms of knowledge, but its claim to a unique status will no longer be sustainable." So predicts Brian Davies, author of the article "Whither Mathematics?", which will appear in the December 2005 issue of Notices of the AMS.