Earth

California mountains rise as groundwater depleted in state's Central Valley

Winter rains and summer groundwater pumping in California's Central Valley make the Sierra Nevada and Coast Ranges sink and rise by a few millimeters each year, creating stress on the state's earthquake faults that could increase the risk of a quake.

Gradual depletion of the Central Valley aquifer because of groundwater pumping also raises these mountain ranges by a similar amount each year – about the thickness of a dime – with a cumulative rise over the past 150 years of up to 15 centimeters (6 inches), according to calculations by a team of geophysicists.

Unified superconductors

Leading-edge imaging and medical diagnostics, but also magnetic levitation trains: these are examples of technology relying on "superconductors". Superconductors are materials in which electrons flow without dissipation and which have very special properties such as expelling all magnetic fields. The physics underlying the phenomenon has only been explained for low-temperature superconductors, those exhibiting their properties at temperatures close to absolute zero.

Chapman University affiliated physicist publishes on the Aharonov-Bohm effect in Nature

ORANGE, Calif. – Chapman University affiliated quantum physicist Yutaka Shikano, Ph.D., has published a milestone paper in the prestigious journal Nature Communications. The title of the article is "Aharonov-Bohm effect with quantum tunneling in linear Paul trap." The Aharonov-Bohm (AB) effect was proposed by Yakir Aharonov, who is the co-director of the Institute for Quantum Studies at Chapman University, and David J. Bohm in 1959.

The physics of ocean undertow

WASHINGTON D.C. May 13, 2014 -- People standing on a beach often feel the water tugging the sand away from under their feet. This is the undertow, the current that pulls water back into the ocean after a wave breaks on the beach.

Large storms produce strong undertows that can strip beaches of sand. By predicting how undertows interact with shorelines, researchers can build sand dunes and engineer other soft solutions to create more robust and sustainable beaches.

Ultrafast laser technique developed to observe electron action

University of Central Florida physicist Zenghu Chang has done it again. For a third time this year, his research group has published an article in a Nature journal.

This time, Chang and his team have developed a new ultrafast light source for observing electron motion in molecules – made up of nuclei and electrons – at the point before the nuclei start to move. By being able to observe what actually happens, scientists can begin to understand how an electron interacts with other electrons, which may help improve the efficiency of solar cells.

Fossil palm beetles 'hind-cast' 50-million-year-old winters

Fifty-million-year-old fossil beetles that fed only on palm seeds are giving Simon Fraser University biologists Bruce Archibald and Rolf Mathewes new information about ancient climates.

According to their research, published online this week in The Proceedings of the National Academy of Sciences, these fossil beetles indicate that during a period of global warming in the geological past, there were mild, frost-free winters extended even in the uplands of ancient western North America.

Radiation from early universe found key to answer major questions in physics

Astrophysicists at UC San Diego have measured the minute gravitational distortions in polarized radiation from the early universe and discovered that these ancient microwaves can provide an important cosmological test of Einstein's theory of general relativity. These measurements have the potential to narrow down the estimates for the mass of ghostly subatomic particles known as neutrinos.

First year student publishes monsoon study

A first year Environmental Science student at The University of Nottingham Malaysia Campus (UNMC) has had a literature review of the Southeast Asian monsoon published in the academic journal Geoscience Frontiers. Her research concluded that future climate warming could lead to a 15 day delay in the monsoon onset in Southeast Asia by the start of the next century.

Quantum trimer -- from a distance

Eight years ago Rudolf Grimm's research group was the first to observe an Efimov state in an ultracold quantum gas. The Russian physicist Vitali Efimov theoretically predicted this exotic bound state of three particles in the 1970s. He forecast that three particles would form a bound state due to their quantum mechanical properties, under conditions when a two-body bound state would be absent. What is even more astounding: When the distance between the particles is increased by factor 22.7, another Efimov state appears, leading to an infinite series of these states.

Which has a more efficient 'engine': A tuna or a whale?

A large gray whale and a much smaller skipjack tuna each propels itself through water. Which is the more efficient swimmer? It has been difficult to compare propulsion efficiencies of animals of different sizes, like comparing apples and oranges, but now Northwestern University researchers have developed a new metric, or standard, to measure individual energy consumption efficiency and make such a comparison possible.

Corn dwarfed by temperature dip suitable for growing in mines, caves

WEST LAFAYETTE, Ind. - Lowering temperatures for two hours each day reduces the height of corn without affecting its seed yield, a Purdue study shows, a technique that could be used to grow crops in controlled-environment facilities in caves and former mines.

Raising the crops in isolated and enclosed environments would help prevent genetically modified pollen and seed from escaping into the ecosystem and crossing with wild plants.

Against the current with lava flows

An Italian astronomer in the 19th century first described them as 'canali' – on Mars' equatorial region, a conspicuous net-like system of deep gorges known as the Noctis Labyrinthus is clearly visible. The gorge system, in turn, leads into another massive canyon, the Valles Marineris, which is 4,000 km long, 200 km wide and 7 km deep. Both of these together would span the US completely from east to west.

Unmanned air vehicle flow separation control using dielectric barrier discharge plasma at high wind

Plasma technology based on Dielectric Barrier Discharge (DBD) has been widely demonstrated to be a novel active flow control method. In order to make the plasma flow control technology more practical, the plasma authority must be improved at high wind speed. Dr. ZHANG Xin and his group from School of Aeronautic, Northwestern Polytechnical University set out to tackle this problem. After 2-years of innovative research, they have developed a novel plasma actuator to improve the plasma authority at high wind speed.

HADES searches for dark matter

Although Dark Energy and Dark Matter appear to constitute over 95 percent of the universe, nobody knows of which particles they are made up. Astrophysicists now crossed one potential Dark Matter candidate – the Dark Photon or U boson – off the list in top position. This is the result of recent HADES experiments, where researchers from the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) and from 17 other European institutes try to pin down the nature of Dark Matter.

Hydrologists find Mississippi River network's buffering system for nitrates is overwhelmed

AUSTIN, Texas – A new method of measuring the interaction of surface water and groundwater along the length of the Mississippi River network adds fresh evidence that the network's natural ability to chemically filter out nitrates is being overwhelmed.