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Submission + - Hints of Life's Start Found in a Giant Virus (simonsfoundation.org)

Submitted by Anonymous Coward
An anonymous reader writes: In the world of microbes, viruses are small — notoriously small. Pithovirus is not. The largest virus ever discovered, pithovirus is more massive than even some bacteria. Most viruses copy themselves by hijacking their host’s molecular machinery. But pithovirus is much more independent, possessing some replication machinery of its own. Pithovirus’s relatively large number of genes also differentiated it from other viruses, which are often genetically simple — the smallest have a mere four genes. Pithovirus has around 500 genes, and some are used for complex tasks such as making proteins and repairing and replicating DNA. “It was so different from what we were taught about viruses,” Abergel said.

The stunning find, first revealed in March, isn’t just expanding scientists’ notions of what a virus can be. It is reframing the debate over the origins of life.

Submission + - The Higgs Boson Should Have Crushed the Universe (discovery.com)

Submitted by astroengine
astroengine writes: This may seem a little far fetched, but if our understanding of the physics behind the recently-discovered Higgs boson (or, more specifically, the Higgs field — the ubiquitous field that endows all stuff with mass) is correct, our Universe shouldn’t exist. That is, however, if another cosmological hypothesis is real, a hypothesis that is currently undergoing intense scrutiny in light of the BICEP2 results.

Submission + - Evidence Of A Correction To The Speed of Light

Submitted by KentuckyFC
KentuckyFC writes: In the early hours of the morning on 24 February 1987, a neutrino detector deep beneath Mont Blanc in northern Italy picked up a sudden burst of neutrinos. Three hours later, neutrino detectors at two other locations picked up a second burst. These turned out to have been produced by the collapse of the core of a star in the Large Magellanic Cloud that orbits our galaxy. And sure enough, some 4.7 hours after this, astronomers noticed the tell-tale brightening of a blue supergiant in that region, as it became a supernova, now known as SN1987a. But why the delay of 7.7 hours from the first burst of neutrinos to the arrival of the photons? Astrophysicists soon realised that since neutrinos rarely interact with ordinary matter, they can escape from the star's core immediately. By contrast, photons have to diffuse through the star, a process that would have delayed them by about 3 hours. That accounts for some of the delay but what of the rest? Now one physicist has the answer--the speed of light through space requires a correction. As a photon travels through space, there is a finite chance that it will form an electron-positron pair. This pair exists for only a brief period of time and then goes on to recombine creating another photon which continues along the same path. This is a well-known process called vacuum polarisation. The new idea is that the gravitational potential of the Milky Way must influence the electron-positron pair because they have mass. This changes the energy of the virtual electron-positron pair, which in turn produces a small change in the energy and speed of the photon. And since the analogous effect on neutrinos is negligible, light will travel more slowly than them through a gravitational potential. According to the new calculations which combine quantum electrodynamics with general relativity, the change in speed accounts more or less exactly for the mysterious time difference. Voila!

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Ocean: A body of water occupying about two-thirds of a world made for man -- who has no gills. -- Ambrose Bierce

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