Mathematics & Physics articlesNew theoritical model eliminates barriers to time travel
A Technion-Israel Institute of Technology physicist has developed a theoretical model of a time machine that could enable future generations to travel into the past. In his paper published in the July issue of Physical Review, noted time-travel theorist Professor Amos Ori provides practical solutions to a number of criteria long seen by other experts as obstacles to the realization of time travel.
Quantum analog of ulam's conjecture can guide molecules reactions
Like navigating spacecraft through the solar system by means of gravity and small propulsive bursts, researchers can guide atoms, molecules and chemical reactions by utilizing the forces that bind nuclei and electrons into molecules (analogous to gravity) and by using light for propulsion. But, knowing the minimal amount of light required, and how that amount changes with the complexity of the molecule, has been a problem.
Indians predated newton 'discovery' by 250 years
A little known school of scholars in southwest India discovered one of the founding principles of modern mathematics hundreds of years before Newton according to new research.
New clues to mechanism for colossal resistance effects
Experiments at the U.S. Department of Energy's Brookhaven National Laboratory shed new light on some materials' ability to dramatically change their electrical resistance in the presence of an external magnetic or electric field. Small changes in resistance underlie many electronic devices, including some computer data storage systems. Understanding and applying dramatic resistance changes, known as colossal magnetoresistance, offers tremendous opportunities for the development of new technologies, including data-storage devices with increased data density and reduced power requirements.
Photon-transistors for the supercomputers of the future
Scientist from the Niels Bohr Institute at University of Copenhagen and from Harvard University have worked out a new theory which describe how the necessary transistors for the quantum computers of the future may be created. The research has just been published in the scientific journal Nature Physics.
Scientists glean turbulent lessons from titan
Ever spilled your drink on an airline because of turbulence? Researchers on both sides of the Atlantic are finding new ways to understand the phenomenon—both in Earth's atmosphere and in that of Saturn's moon Titan, aided by data gathered from the Cassini-Huygens probe.
Scientists take giant step forward in understanding exotic nuclei
Developing good predictive powers of how all nuclei work is critical to advance our understanding of the universe. The vast nuclear landscape, which is thought to consist of about 6,000 isotopes is not well charted and half the nuclei remain unknown.
Researchers knock down theory about nanofluids
MIT engineers have shown that nanofluids, which once held promise as a super-coolant, do not have the theoretical cooling capabilities many scientists believed they had.
Molecules of positronium observed in the laboratory for the first time
Physicists at UC Riverside have created molecular positronium, an entirely new object in the laboratory. Briefly stable, each molecule is made up of a pair of electrons and a pair of their antiparticles, called positrons.
Toll charges reduce travel time
A smart introduction of a variable toll charge, with different rates at different departure times, reduces traffic jams. Even small toll charges can exert a large effect on the total travel time, concludes Dutch researcher Dusica Joksimovic.
Researchers improve ability to write and store information on electronic devices
New research led by the U.S. Department of Energy's Argonne National Laboratory physicist Matthias Bode provides a more thorough understanding of new mechanisms, which makes it possible to switch a magnetic nanoparticle without any magnetic field and may enable computers to more accurately write and store information.
Scientists take unique measurement of exotic oxygen nucleus
Ohio University physicist Andreas Schiller and other researchers have made a unique measurement of an exotic oxygen nucleus, leading scientists one step closer to deciphering the behavior of the element at its limits of existence.
A better definition for the kilogram?
Two U.S. professors – a physicist and mathematician – say it's time to define the kilogram in a new and more elegant way. They've launched a campaign aimed at redefining the kilogram as the mass of a very large – but precisely-specified – number of carbon-12 atoms.
Quantum physics cools down computers
The future of Moore's famous law—that the number of transistors squeezed onto a computer chip can be doubled about every two years—is widely seen as threatened by the damaging heat generated by the chips themselves as their transistors become more densely packed.
Physicist shining a light on mysterious 'dark matter'
We've all been taught that our bodies, the Earth, and in fact all matter in the universe is composed of tiny building blocks called atoms. Now imagine if this weren't the case. This mind-bending concept is at the core of the scientific research that one Florida State University professor -- and hundreds of his colleagues all over the world -- are pursuing.
Even without math, ancients engineered sophisticated machines
Move over, Archimedes. A researcher at Harvard University is finding that ancient Greek craftsmen were able to engineer sophisticated machines without necessarily understanding the mathematical theory behind their construction.
Physicist defends Einstein's theory and 'speed of gravity' measurement
Scientists have attempted to disprove Albert Einstein's theory of general relativity for the better part of a century. After testing and confirming Einstein's prediction in 2002 that gravity moves at the speed of light, a professor at the University of Missouri-Columbia has spent the past five years defending the result, as well as his own innovative experimental techniques for measuring the speed of propagation of the tiny ripples of space-time known as gravitational waves.
Breaking the barrier toward nanometer x-ray resolution
A team of researchers at the U.S. Department of Energy's Brookhaven National Laboratory have overcome a major obstacle for using refractive lenses to focus x-rays. This method will allow the efficient focusing of x-rays down to extremely small spots and is an important breakthrough in the development of a new, world-leading light source facility that promises advances in nanoscience, energy, biology, and materials research.
Physicists propose new method of measuring the weak interaction
A particular class of hydrogen atoms may prove ideal for the study of one of the four fundamental forces of physics, according to research performed at the U.S. Department of Energy's Argonne National Laboratory.
Mathematicians defy gravity
Droplets of liquid have been shown to travel uphill, rather than sliding down as expected, when the surface they are on is vigorously shaken up and down.