Tag Archives: physicist

How Evolution Shapes the Geometries of Life

By Guest PostFebruary 20, 2014Scienceamos maritan, andrea rinaldo, botanist, convergent evolution, elephant, evolution, generations of scientists, geometric arguments, geometries of life, human evolution, italy, jayanth banavar, kleibers law, lifetime, max kleiber, peter griffin, physicist, shape, swiss biologist, todd cooke, university of maryland, university of padua

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…)

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

By Guest PostJune 21, 2013Scienceaustin, charged particles, conventional accelerator, electrons, Environment, factor, gev, gev electron beam, gigaelectronvolts, laser plasma accelerator, laser pulse, mike downer, motorboat, multi gigaelectronvolt, particle accelerator, physicist, physicists, puff of gas, science research, space charge fields, tabletop, Technology, texas petawatt laser, toshiki tajima, university of texas, xray source

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…)

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

By Guest PostJanuary 12, 2013Environmentacceptor, advanced light source, affordable, als, als beamlines, amount, berkeley lab, brian collins, christopher mcneill, convert, crystallinity, donor, earth, efficient, electricity, eliot gann, energy use, exciton journey, fossil fuels, fullerene solar film, harald ade, john tumbleston, land mass, nanometers, north Carolina, organic cell, photovoltaic cells, photovoltaic devices, physicist, polymer, r soxs, research, resonant soft, silicon based, size matters, solar cell, solar energy, solvent diiodooctane, state university, stxm, sunlight, ultraviolet light beams, volume, x ray, x ray scattering, zhe li

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…)

Slinky Science Inspires African School Children

By Guest PostDecember 17, 2012Educationafrican school children, biological photonics, class, cosmetics, exeter, fundamental scientific ideas, glass prisms, interactive demonstration, iridescent butterflies, light sticks, malawi, mzuzu university, natural photonics, paper applications, pete vukusic, physicist, poorest area, pupils and teachers, slinky springs, southern africa, spring, teaching methods, university

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…)

Researchers Reveal Structure of Carbon’s ‘Hoyle State’

By Guest PostDecember 11, 2012Sciencealpha clusters, alpha particles, bent arm, carbon 12, dean lee, element, evgeny epelbaum, german colleague, helium 4 nuclei, hermann krebs, hoyle state, lattice, life on earth, neutrons, north Carolina, nucleons, particle, physicist, picture, protons, simulate, snapshot, state university, structure, timo laehde, ulf g meissner

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…)

Space Life

By Guest PostDecember 7, 2012Scienceask magazine, astrobiology, biology, c elegans, chandran sabanayagam, cubesat projects, dbi, desg, DNA, does life exist, earth, Environment, evolution, microbes, microscopic worms, NASA, physicist, proteins, space life, space research, telemetry, trl3, universe, zero gravity

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…)

Ultracold Experiments Heat Up Quantum Research

By Guest PostMarch 20, 2012Scienceabsolute zero, atomic realm, atoms, birth of universe, black hole, ccd camera, chen lung hung, cheng chin, cosmology, crystals, diverse phenomena, early universe, electron, gravitational dynamics, magnetic materials, nano kelvin, physicist, quantum criticality, quantum phase transition, subatomic particle, subir sachdev, superconductors, thomas rosenbaum, ultracold atom, ultracold state, ultracold temperature, university of chicago, xibo zhang

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…)

Mr. Fusion Helps Students Build a Nuclear Reactor

By Guest PostAugust 18, 2011Science, Technologyalbert babb, brian greene, carl greninger, farnsworth hirsch fusor, garage, glassification of nuclear waste, high end suv, iec 9000, jayce glenn, microsoft employee, microsoft it operations, microsoft research science fair, new york, nuclear reactor, physicist, physics, thermonuclear reactor, united states operates 104 nuclear reactors, voila fusion, x ray machine

*Microsoft employee Carl Greninger helped a team of young students build a working nuclear reactor in his garage. He hopes the project can inspire a passion for physics in students around the country.*

REDMOND, Wash. – Sometimes you have to smash a few atoms to excite people about science.

So says Carl Greninger, a program manager in Microsoft IT Operations by day and full-fledged physics fanatic by night. That’s why he decided to help some young students get hands-on experience with something they couldn’t find in their classrooms: a working thermonuclear reactor.

For the past year, a group of local students – some as young as 13 years old – have met at Greninger’s garage every Friday night to build a type of fusion reactor known as a Farnsworth–Hirsch Fusor. Dubbed IEC-9000, their machine has been fusing atoms and producing neutrons since May. It cost about as much as a high-end SUV, weighs 1,400 pounds, and generates temperatures hotter than the surface of the sun. (more…)