Eight billion years ago, rays of light from distant galaxies began their long journey to Earth. That ancient starlight has now found its way to a mountaintop in Chile, where the newly constructed Dark Energy Camera, the most powerful sky-mapping machine ever created, has captured and recorded it for the first time.
That light may hold within it the answer to one of the biggest mysteries in physics: Why the expansion of the universe is speeding up. (more…)
While wave watching is a favorite pastime of beachgoers, few notice what is happening in the shallowest water. A closer look by two University of Colorado Boulder applied mathematicians has led to the discovery of interacting X- and Y-shaped ocean waves that may help explain why some tsunamis are able to wreak so much havoc.
Professor Mark Ablowitz and doctoral student Douglas Baldwin repeatedly observed such wave interactions in ankle-deep water at both Nuevo Vallarta, Mexico, and Venice Beach, Calif., in the Pacific Ocean — interactions that were thought to be very rare but which actually happen every day near low tide. There they saw single, straight waves interacting with each other to form X- and Y-shaped waves as well as more complex wave structures, all predicted by mathematical equations, said Ablowitz. (more…)
A little physics goes a long way on the tennis court. In this edition of Science Xplained, Dr. Ainissa Ramirez discusses tennis racket technology–from wood and cow intestines to carbon fiber and nylon — and the principles behind topspin. *Source: Yale University
For two molecules on blind date, new method predicts potential for attraction or repulsion
Krzysztof Szalewicz, professor of physics and astronomy at the University of Delaware, and Rafal Podeszwa of the University of Silesia Institute of Chemistry in Poland have developed and validated a more accurate method for predicting the interaction energy of large molecules, such as biomolecules used to develop new drugs.
The research is reported as a communication in the April 27 issue of the Journal of Chemical Physics, which is the most highly cited journal in atomic, molecular and chemical physics according to Thomson Reuters. The journal is published by the American Institute of Physics. Despite appearing at the end of April, the paper was on the list of the 20 most-read articles in JCP for that month. (more…)
UA student Jason Xu has been recognized by the College of Science for his undergraduate research.
Wuhan, China and Tucson, Ariz.: These cities are thousands of miles apart, but they have one commonality – University of Arizona student Jason Xu.
A Chinese native and mathematics senior in the Honors College, Xu was selected as the recipient of this year’s Excellence in Undergraduate Research award by the UACollege of Science at its Galileo Circle reception event.
The award “is a huge honor and means a lot to me. I feel really good to be representing the math department,” Xu said. (more…)
As a professor of astronomy and physics, Priyamvada Natarajan doesn’t balk at taking risks. She has modeled the upper limits of “monster” black holes and analyzed the consistency of dark matter. As a theorist, she notes, intellectual risk is par for the course.
But as a woman in science, risk-taking has another meaning, she says. Studying in a predominantly male field, Natarajan considers herself fortunate to have been surrounded by exceptional mentors throughout her career. She recognizes that her experience was an unusual one. Many of her female classmates at the Massachusetts Institute of Technology (MIT) did not receive the same level of encouragement to continue their studies and research, she notes. (more…)
*Brown University physicists have set the strongest limit for the mass of dark matter, the mysterious particles believed to make up nearly a quarter of the universe. The researchers report in Physical Review Letters that dark matter must have a mass greater than 40 giga-electron volts. The distinction is important because it casts doubt on recent results from underground experiments that have reported detecting dark matter.*
PROVIDENCE, R.I. [Brown University] — If dark matter exists in the universe, scientists now have set the strongest limit to date on its mass.
In a paper to be published on Dec. 1 in Physical Review Letters (available in pdf), Brown University assistant professor Savvas Koushiappas and graduate student Alex Geringer-Sameth report that dark matter must have a mass greater than 40 giga-electron volts in dark-matter collisions involving heavy quarks. (The masses of elementary particles are regularly expressed in term of electron volts.) Using publicly available data collected from an instrument on NASA’s Fermi Gamma-ray Space Telescope and a novel statistical approach, the Brown pair constrained the mass of dark matter particles by calculating the rate at which the particles are thought to cancel each other out in galaxies that orbit the Milky Way galaxy. (more…)
COLUMBUS, Ohio – Scientists under the age of 40 used to make the majority of significant breakthroughs in chemistry, physics and medicine – but that is no longer the case, new research suggests.
A study of Nobel Laureates from 1901 to 2008 in these three fields examined the age at which scientists did their prize-winning work.
Results showed that before 1905, about two-thirds of winners in all three fields did their prize-winning work before age 40, and about 20 percent did it before age 30. (more…)
