Tag Archives: physicist

How Evolution Shapes the Geometries of Life

COLLEGE PARK, Md. – Why does a mouse’s heart beat about the same number of times in its lifetime as an elephant’s, although the mouse lives about a year, while an elephant sees 70 winters come and go? Why do small plants and animals mature faster than large ones? Why has nature chosen such radically different forms as the loose-limbed beauty of a flowering tree and the fearful symmetry of a tiger?

These questions have puzzled life scientists since ancient times. Now an interdisciplinary team of researchers from the University of Maryland and the University of Padua in Italy propose a thought-provoking answer based on a famous mathematical formula that has been accepted as true for generations, but never fully understood. In a paper published the week of Feb. 17, 2014 in the Proceedings of the National Academy of Sciences, the team offers a re-thinking of the formula known as Kleiber’s Law. Seeing this formula as a mathematical expression of an evolutionary fact, the team suggests that plants’ and animals’ widely different forms evolved in parallel, as ideal ways to solve the problem of how to use energy efficiently. (more…)

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Particle Accelerator That Can Fit on a Tabletop Opens New Chapter for Science Research

AUSTIN, Texas — Physicists at The University of Texas at Austin have built a tabletop particle accelerator that can generate energies and speeds previously reached only by major facilities that are hundreds of meters long and cost hundreds of millions of dollars to build.

“We have accelerated about half a billion electrons to 2 gigaelectronvolts over a distance of about 1 inch,” said Mike Downer, professor of physics in the College of Natural Sciences. “Until now that degree of energy and focus has required a conventional accelerator that stretches more than the length of two football fields. It’s a downsizing of a factor of approximately 10,000.” (more…)

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New Path to More Efficient Organic Solar Cells Uncovered at Berkeley Lab’s Advanced Light Source

Why are efficient and affordable solar cells so highly coveted? Volume. The amount of solar energy lighting up Earth’s land mass every year is nearly 3,000 times the total amount of annual human energy use. But to compete with energy from fossil fuels, photovoltaic devices must convert sunlight to electricity with a certain measure of efficiency. For polymer-based organic photovoltaic cells, which are far less expensive to manufacture than silicon-based solar cells, scientists have long believed that the key to high efficiencies rests in the purity of the polymer/organic cell’s two domains – acceptor and donor. Now, however, an alternate and possibly easier route forward has been shown.

Working at Berkeley Lab’s Advanced Light Source (ALS), a premier source of X-ray and ultraviolet light beams for research, an international team of scientists found that for highly efficient polymer/organic photovoltaic cells, size matters. (more…)

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Slinky Science Inspires African School Children

A University of Exeter physicist has inspired hundreds of African school children to engage with science during a whirlwind outreach tour to Malawi.

Professor Pete Vukusic used simple interactive demonstrations including slinky springs, glass prisms, light sticks and iridescent butterflies to enthral large classes of pupils and teachers in underprivileged rural schools.

The charismatic lecturer combined use of the demos and an interactive and engaging teaching style to explain fundamental and modern science principles to students who are used to formal instructional teaching methods. Professor Vukusic hopes his visit will both help to inspire science learning in these schools and help their teachers adapt to more modern techniques that engage young people more effectively. (more…)

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Researchers Reveal Structure of Carbon’s ‘Hoyle State’

A North Carolina State University researcher has taken a “snapshot” of the way particles combine to form carbon-12, the element that makes all life on Earth possible. And the picture looks like a bent arm.

Carbon-12 can only exist when three alpha particles, or helium-4 nuclei, combine in a very specific way. This combination is known as the Hoyle state. NC State physicist Dean Lee and German colleagues Evgeny Epelbaum, Hermann Krebs and Ulf-G. Meissner had previously confirmed the existence of the Hoyle state using a numerical lattice that allowed the researchers to simulate how the protons and neutrons interact. When the researchers ran their simulations on the lattice, the Hoyle state appeared together with other observed states of carbon-12, proving the theory correct from first principles. (more…)

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Space Life

NASA funds astrobiology research by Delaware Biotechnology Institute scientist

Does life exist anywhere else in the universe? That’s the type of broad but poignant question NASA likes to ask, according to Chandran Sabanayagam, associate scientist in the Bioimaging Center at the Delaware Biotechnology Institute (DBI). And he would know, because he’s preparing to help answer it.

NASA will receive $100 billion from the federal government over the next five years to assure America is number one in space exploration, according to Astrobiology.com. As part of its push to seek new partnerships and broaden its vision, NASA is offering grants to people conducting transformational science. With this opportunity, Sabanayagam is merging his love of physics and biology. (more…)

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Nuclear Waste-Burning Technology Could Change the Face of Nuclear Energy

AUSTIN, Texas — University of Texas at Austin physicists have been awarded a U.S. patent for an invention that could someday be used to turn nuclear waste into fuel, thus removing the most dangerous forms of waste from the fuel cycle.

The researchers — Mike Kotschenreuther, Prashant Valanju and Swadesh Mahajan of the College of Natural Sciences — have patented the concept for a novel fusion-fission hybrid nuclear reactor that would use nuclear fusion and fission together to incinerate nuclear waste. Fusion produces energy by fusing atomic nuclei, and fission produces energy by splitting atomic nuclei. (more…)

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Ultracold Experiments Heat Up Quantum Research

University of Chicago physicists have experimentally demonstrated, for the first time, that atoms chilled to temperatures near absolute zero may behave like seemingly unrelated natural systems of vastly different scales, offering potential insights into links between the atomic realm and deep questions of cosmology.

This ultracold state, called “quantum criticality,” hints at similarities between such diverse phenomena as the gravitational dynamics of black holes or the exotic conditions that prevailed at the birth of the universe, said Cheng Chin, associate professor in physics at UChicago. The results could even point to ways of simulating cosmological phenomena of the early universe by studying systems of atoms in states of quantum criticality. (more…)

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