Quantum bounce could make black holes explode : Nature News & Comment

Quantum bounce could make black holes explode : Nature News & Comment: The theory suggests that the transition from black hole to white hole would take place right after the initial formation of the black hole, but because gravity dilates time, outside observers would see the black hole lasting billions or trillions of years or more, depending on its size. If the authors are correct, tiny black holes that formed during the very early history of the Universe would now be ready to pop off like firecrackers and might be detected as high-energy cosmic rays or other radiation. In fact, they say, their work could imply that some of the dramatic flares commonly considered to be supernova explosions could in fact be the dying throes of tiny black holes that formed shortly after the Big Bang.

The Measurement That Would Reveal The Universe As A Computer Simulation - Technology Review

The Measurement That Would Reveal The Universe As A Computer Simulation - Technology Review: The question that Beane and co ask is whether the lattice spacing imposes any kind of limitation on the physical processes we see in the universe...

They say that the lattice spacing imposes a fundamental limit on the energy that particles can have. That's because nothing can exist that is smaller than the lattice itself.

So if our cosmos is merely a simulation, there ought to be a cut off in the spectrum of high energy particles...


"The most striking feature...is that the angular distribution of the highest energy components would exhibit cubic symmetry in the rest frame of the lattice, deviating significantly from isotropy," they say.

Flaring black holes may solve cosmic ray puzzle - New Scientist - New Scientist

Flaring black holes may solve cosmic ray puzzle: Then they found a clue: gamma-ray burst GRB110328A, which happened in March 2011. Its afterglow persisted for over a week, instead of a few hours like normal ones. The culprit was most likely a star falling into a galaxy's central black hole. This would make a weak black hole flare up, producing a burst of gamma rays that in turn spits out cosmic rays, suggests Farrar...

Blog - Antiproton Radiation Belt Discovered Around Earth

Blog - Antiproton Radiation Belt Discovered Around Earth: Now the PAMELA team has analysed the 850 days of data, looking only at the times when the spacecraft was in the South Atlantic Anomaly (about 1.7 per cent of this time).

Lo and behold, these guys found 28 antiprotons. That's about three orders of magnitude more than you'd expect to find in the solar wind, proving that the particles really are trapped and stored in this belt.

First Observation of Antihelium� - Technology Review

First Observation of Antihelium� - Technology Review: What's important about this observation is that antihelium-4 seems to occur at exactly the rate predicted by thermodynamics. So unless there's some other mechanism for making it in vastly greater quantities, we're unlikely to see a naturally occurring version, no matter how hard we look.

So "any observation of antihelium or even heavier antinuclei in space would indicate the existence of a large amount of antimatter elsewhere in the Universe," say the STAR collaboration.

Physicists investigate lower dimensions of the universe

Physicists investigate lower dimensions of the universe: So far, there may already be one piece of experimental evidence for the existence of a lower-dimensional structure at a higher energy scale. When observing families of cosmic ray particles in space, scientists found that, at energies higher than 1 TeV, the main energy fluxes appear to align in a two-dimensional plane. This means that, above a certain energy level, particles propagate in two dimensions rather than three dimensions.

In the current study, Mureika and Stojkovic have proposed a second test for lower dimensions that would provide independent evidence for their existence. The test is based on the assumption that a (2 + 1)-dimensional spacetime, which is a flat plane, has no gravitational degrees of freedom. This means that gravity waves and gravitons cannot have been produced during this epoch. So the physicists suggest that a future gravitational wave detector looking deep into space might find that primordial gravity waves cannot be produced beyond a certain frequency, and this frequency would represent the transition between dimensions. Looking backwards, it would appear that one of our spatial dimensions has “vanished.”
The scientists added that it should be possible, though perhaps more difficult, to test for the existence of (1 + 1)-dimensional spacetime.

A Bid To Implode Cosmic Ray Theory - Science News

A Bid To Implode Cosmic Ray Theory - Science News: "Magnetic fields in a supernova should accelerate both hydrogen and helium particles in the same way: Graph the mathematical description of this push, and the curve for each particle should have the same slope. But in the PAMELA data, Picozza found a difference in these slopes that a single shock wave can’t explain."

Milky Way magnets solve cosmic ray conundrum - space - 17 August 2010 - New Scientist

Milky Way magnets solve cosmic ray conundrum: "The crux of their idea is the recent finding that the explosions in other galaxies believed to form cosmic rays, such as gamma ray bursts, can happen in the Milky Way too.

To find out if this could explain the heavy cosmic rays, Kusenko's team calculated the numbers of protons and nuclei that such explosions would produce and whether the Milky Way's magnetic field would be able to retain them.

At low energies, both protons and nuclei were deflected by the magnetic field and therefore retained in the galaxy for millions of years. But at high energies, the protons tended to escape while the heavier, less mobile nuclei hung around.

This could account for the increase in heavy cosmic rays seen at high energies by Auger, say the team. "Gamma ray bursts inject high-energy nuclei that get trapped in the galactic magnetic field and are observed some million years later as cosmic rays," says Kusenko."