Toggle light / dark theme

Realistic climate simulations require huge reserves of computational power. An LMU study now shows that new algorithms allow interactions in the atmosphere to be modeled more rapidly without loss of reliability.

Forecasting global and local climates requires the construction and testing of mathematical . Since such models must incorporate a plethora of physical processes and interactions, climate simulations require enormous amounts of . And even the best models inevitably have limitations, since the phenomena involved can never be modeled in sufficient detail. In a project carried out in the context of the DFG-funded Collaborative Research Center “Waves to Weather”, Stephan Rasp of the Institute of Theoretical Meteorology at LMU (Director: Professor George Craig) has now looked at the question of whether the application of can improve the efficacy of climate modelling. The study, which was performed in collaboration with Professor Mike Pritchard of the University of California at Irvine und Pierre Gentine of Columbia University in New York, appears in the journal PNAS.

General circulation models typically simulate the global behavior of the atmosphere on grids whose cells have dimensions of around 50 km. Even using state-of-the-art supercomputers the relevant that take place in the atmosphere are simply too complex to be modelled at the necessary level of detail. One prominent example concerns the modelling of clouds which have a crucial influence on climate. They transport heat and moisture, produce precipitation, as well as absorb and reflect solar radiation, for instance. Many clouds extend over distances of only a few hundred meters, much smaller than the grid cells typically used in simulations – and they are highly dynamic. Both features make them extremely difficult to model realistically. Hence today’s models lack at least one vital ingredient, and in this respect, only provide an approximate description of the Earth system.

Read more

New research confronts the elephant in the room—the ‘trilemma’ of population growth, economic growth and environmental sustainability—and reveals the vast incompatibility of current models of economic development with environmental sustainability.

Using data collected from across the globe, national economies and natural resource use were closely examined by an international team of scientists using a mathematical model.

The results suggest that as long as our economic system retains its current structure, and if continues, both high- and low-income countries will fail to achieve environmental sustainability.

Read more

Black women, especially, played a crucial role in the pool, providing mathematical data for NASA’s first successful space missions, including Alan Shepherd’s 1961 mission and John Glenn’s pioneering orbital spaceflight.

Read more

Jason Padgett grew up struggling in school — until one night in 2002 when he was attacked in a bar and everything changed. Padgett said after the incident, he was using areas of the brain he didn’t previously have access to; he experienced choppy vision, was drawing intricate shapes and was seeing complex mathematical objects everywhere. Dr. Darold Treffert, a world renowned expert on savants, later diagnosed Padgett with acquired savant syndrome, which explained Padgett’s new skills. Padgett joins Megyn Kelly TODAY to share his story.

Read more

A trio of physicists with Columbia University is making waves with a new theory about phonons—they suggest they might have negative mass, and because of that, have negative gravity. Angelo Esposito, Rafael Krichevsky and Alberto Nicolis have written a paper to support their theory, including the math, and have uploaded it to the xrXiv preprint server.

Most theories depict waves as more of a collective event than as physical things. They are seen as the movement of molecules bumping against each other like balls on a pool table—the energy of one ball knocking the next, and so on—any motion in one direction is offset by motion in the opposite direction. In such a model, sound has no mass, and thus cannot be impacted by . But there may be more to the story. In their paper, the researchers suggest that the current theory does not fully explain everything that has been observed.

In recent years, physicists have come up with a word to describe the behavior of at a very small scale—the phonon. It describes the way sound vibrations cause complicated interactions with molecules, which allows the sound to propagate. The term has been useful because it allows for applying principles to sound that have previously been applied to actual particles. But no one has suggested that they actually are particles, which means they should not have mass. In this new effort, the researchers suggest the phonon could have negative , and because of that, could also have negative gravity.

Read more

By Chelsea Whyte

Swirling patterns in the sky may be signs of black holes that survived the destruction of a universe before the big bang.

“What we claim we’re seeing is the final remnant after a black hole has evaporated away in the previous aeon,” says Roger Penrose, a mathematical physicist at the University of Oxford.

Read more