Collaboration shines possible light on objects 'weirder than black holes'

Researchers from Duke University and the University of Cambridge think there
is a way to determine whether some black holes are not actually black.

Finding such an unmasked form of what physicists term a singularity "would
shock the foundation of general relativity," said Arlie Petters, a Duke
professor of mathematics and physics who worked with Marcus Werner,
Cambridge graduate student in astrophysics, on a report posted online
Monday, Sept. 24, for the research journal Physical Review D.

"It would show that nature has surprises even weirder than black holes,"
Petters added.

Albert Einstein originally theorized that stars bigger than the sun can
collapse and compress into singularities, entities so confining and
massively dense that the laws of physics break down inside them.

Astronomers have since found indirect evidence for these entities, which are
popularly known as black holes because of the "cosmic censorship
conjecture." This conjecture is that "realistic" singularities -- meaning
those that can be formed in nature -- must always hide within a barrier
known as an "event horizon" from which light can never escape. That makes
them appear perpetually black to the rest of the universe.

But cosmic censorship is "an open conjecture that is very difficult to
prove, and very difficult to disprove," said Petters.

And, despite the general support for the universality of black holes, Kip
Thorne and John Preskill, two experts in the cosmology of relativity at the
California Institute of Technology, have suggested for more than a decade
that naked singularities could exist in certain instances. Now Petters and
Werner have devised a way to test for their presence.

Astronomers cannot say for sure whether all black holes are actually black,
having never fully penetrated the obscuring outward matter surrounding such
objects, Petters said. As their main evidence, scientists can only point to
effects that the massive gravitational pull of certain unseen entities exert
on surrounding matter. Those effects include emissions of highly energetic
radiation, or the extreme orbits of nearby stars.

Petters is an expert in "gravitational lensing," another effect of
relativity that permits massive sources of gravity to split light from
background astronomical features into multiple images.

In earlier reports in the November, 2005 and February, 2006 issues of
Physical Review D, he and Charles Keeton of Rutgers University suggested a
way to use gravitational lensing to show whether cosmic censorship can ever
be violated.

However, that evaluation was limited to non-spinning singularities that are
considered only theoretically possible. The suspected singularities
astronomers have found in space so far all appear to be rapidly spinning,
sometimes at more than 1,000 times a second.

So Petters and Werner teamed up to see if they could generalize such an
application of gravitational lensing to all realistic spinning
singularities. Their surprising result was yes, Petters said.

In work supported by the National Science Foundation in the United States
and the Science and Technology Facilities Council in the United Kingdom, the
pair employed a finding that a black hole could be shed of its event horizon
and become a naked singularity if its angular momentum -- an effect of its
spin -- is greater than its mass.

That would translate into a spin of a few thousand rotations a second in the
case of a black hole weighing about 10 times more than our Sun, said Werner.

In the event that the required conditions were met, Petters' and Werner's
calculations show that a naked singularity's massive gravitation would split
the light of background stars or galaxies in telltale ways that are
potentially detectable by astronomers using existing or soon-to-be
instruments.

Those possible ways are outlined by six different equations in their study
that connect a singularity's spin to the separations, angular alignments and
brightness of the two split images.

"If you ask me whether I believe that naked singularities exist, I will tell
you that I'm sitting on the fence," said Petters. "In a sense, I hope they
are not there. I would prefer to have covered-up black holes. But I'm still
open-minded enough to entertain the 'otherwise' possibility."

Source: Duke University
http://www.physorg.com/news109867100.html

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Posted by
Robert Karl Stonjek

On Sep 24, 8:11 pm, "Robert Karl Stonjek"
wrote:
Collaboration shines possible light on
objects 'weirder than black holes'

Thanks, Robert. Way cool.

David A. Smith

On Sep 24, 11:11 pm, "Robert Karl Stonjek"
wrote:
Collaboration shines possible light on objects 'weirder than black holes'


Look-up "mono pole". Since "science" could not find any existence of
mono poles or multipoles and only dipoles (hence arrow of time). These
are related to direction of energy emination. For this energy
eminating reason, it is plausible the big bang did not occur in all
directions simultaneously (but through a manifold tunneling fashion)
and LIKEWISE perhaps a black hole does not implode from all
directions.