Researchers at the University of Rochester have uncovered how giant magnetic fields up to a billion, billion miles across, such as the one that envelopes our galaxy, are able to take shape despite a mystery that suggested they should collapse almost before theyd begun to form. Astrophysicists have long believed that as these large magnetic fields grow, opposing small-scale fields should grow more quickly, thwarting the evolution of any giant magnetic field. The team discovered instead that the simple motion of gas can fight against those small-scale fields long enough for the large fields to form. The results are published in a recent issue of Physical Review Letters.
"Understanding exactly how these large-scale fields form has been a problem for astrophysicists for a long time," says Eric Blackman, assistant professor of physics and astronomy. "For almost 50 years the standard approaches have been plagued by a fundamental mystery that we have now resolved."
The mechanism, called a dynamo, that creates the large-scale field twists up the magnetic field lines as if they were elastic ribbons embedded in the sun, galaxy or other celestial object. Turbulence kicked up by shifting gas, supernovae, or nearly any kind of random movement of matter, combined with the fact that the star or galaxy is spinning carries these ribbons outward toward the edges. As they expand outward they slow like a spinning skater extending her arms and the resulting speed difference causes the ribbons to twist up into a large helix, creating the overall orderly structure of the field.
Jonathan Sherwood | EurekAlert!
From the cosmos to fusion plasmas, PPPL presents findings at global APS gathering
13.11.2018 | DOE/Princeton Plasma Physics Laboratory
A two-atom quantum duet
12.11.2018 | Institute for Basic Science
Biochips have been developed at TU Wien (Vienna), on which tissue can be produced and examined. This allows supplying the tissue with different substances in a very controlled way.
Cultivating human cells in the Petri dish is not a big challenge today. Producing artificial tissue, however, permeated by fine blood vessels, is a much more...
Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.
In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...
On Saturday, 10 November 2018, the research icebreaker Polarstern will leave its homeport of Bremerhaven, bound for Cape Town, South Africa.
When choosing materials to make something, trade-offs need to be made between a host of properties, such as thickness, stiffness and weight. Depending on the application in question, finding just the right balance is the difference between success and failure
Now, a team of Penn Engineers has demonstrated a new material they call "nanocardboard," an ultrathin equivalent of corrugated paper cardboard. A square...
Physicists at ETH Zurich demonstrate how errors that occur during the manipulation of quantum system can be monitored and corrected on the fly
The field of quantum computation has seen tremendous progress in recent years. Bit by bit, quantum devices start to challenge conventional computers, at least...
09.11.2018 | Event News
06.11.2018 | Event News
23.10.2018 | Event News
14.11.2018 | Materials Sciences
14.11.2018 | Health and Medicine
14.11.2018 | Life Sciences