Friday, January 21, 2011

Some Interesting Science Papers

My friend Physicist Oliver K. Manuel has a paper out explaining that the sun is not an ordinary star that "burns" strictly Hydrogen, but a neutron star with a Hydrogen mantle. The paper is rather technical but I can give you the flavor of it with an excerpt from the Conclusion.

Dynamic competition between gravitational attraction and neutron repulsion sustains our dynamic universe, the Sun, and life on planet Earth. Nuclear matter in the solar system is mostly dissociating rather than coalescing (fusing together). As shown in the above table, the potential energy per nucleon in the solar core is almost twice that available from hydrogen fusion. If the bulk of the Sun's mass is in a central neutron star and luminosity comes from the reactions listed above, then solar luminosity might have been higher by ~1-2% during the critical evolutionary period when the Standard Solar Model predicts frozen oceans and a "faint early Sun" [121]. Circular polarized light from the neutron star may have been separated d- and l-amino acids before the appearance of life [101].
The paper seems to explain a lot of things about our solar system and the sun. Like why life on Earth is made up of almost exclusively right hand molecules.

The second paper deals with superconductors. The Talk Polywell guys gave me the hint. What is so special about the new superconductor? It is made by shining laser light on a non-conductor.
The team from Oxford[England - ed.], Germany and Japan are said to have observed conclusive signatures of superconductivity after hitting a non-superconductor with a strong burst of laser light.

‘We have used light to turn a normal insulator into a superconductor,’ said Prof Andrea Cavalleri of the Department of Physics at Oxford University and the Max Planck Department for Structural Dynamics, Hamburg. ‘That’s already exciting in terms of what it tells us about this class of materials. But the question now is can we take a material to a much higher temperature and make it a superconductor?’

The material the researchers used is closely related to high-temperature copper oxide superconductors, but the arrangement of electrons and atoms normally act to frustrate any electronic current.

In the journal Science, they describe how a strong infrared laser pulse was used to perturb the positions of some of the atoms in the material. The compound, held at a temperature just 20 degrees above absolute zero, almost instantaneously became a superconductor for a fraction of a second, before relaxing back to its normal state.
Why is this important? After all we already have superconductors that operate continuously at that temperature without lasers.
‘We have shown that the non-superconducting state and the superconducting one are not that different in these materials, in that it takes only a millionth of a millionth of a second to make the electrons ‘synch up’ and superconduct,’ said Professor Cavalleri. ‘This must mean that they were essentially already synched in the non-superconductor, but something was preventing them from sliding around with zero resistance. The precisely tuned laser light removes the frustration, unlocking the superconductivity.’

The advance immediately offers a new way to probe with great control how superconductivity arises in this class of materials.

The researchers are hopeful it could also offer a new route to obtaining superconductivity at higher temperatures. If superconductors that work at room temperature could be achieved, it would open up many more technological applications.
So right now it is all about research. But you never know what you might learn if you start poking with the proper stick in the right places.

Some books:

The Diversity Of Neutron Stars: Nearby Thermally Emitting Neutron Stars And The Compact Central Objects In Supernova Remnants

Superconductivity: A Very Short Introduction

Introduction to Superconductivity: Second Edition

Cross Posted at Classical Values

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