This illustration represents the best evidence to date that the direct collapse of a gas cloud produced supermassive black holes in the early Universe. Researchers combined data from NASA’s Chandra, Hubble, and Spitzer telescopes to make this discovery.
Credits: NASA/CXC/STScI

Using data from NASA’s Great Observatories, astronomers have found the best evidence yet for cosmic seeds in the early universe that should grow into supermassive black holes.

Researchers combined data from NASA’s Chandra X-ray Observatory, Hubble Space Telescope, and Spitzer Space Telescope to identify these possible black hole seeds. They discuss their findings in a paper that will appear in an upcoming issue of the Monthly Notices of the Royal Astronomical Society.

“Our discovery, if confirmed, explains how these monster black holes were born,” said Fabio Pacucci of Scuola Normale Superiore (SNS) in Pisa, Italy, who led the study. “We found evidence that supermassive black hole seeds can form directly from the collapse of a giant gas cloud, skipping any intermediate steps.”

Scientists believe a supermassive black hole lies in the center of nearly all large galaxies, including our own Milky Way. They have found that some of these supermassive black holes, which contain millions or even billions of times the mass of the sun, formed less than a billion years after the start of the universe in the Big Bang.

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May 24, 2016

Dark matter is a mysterious substance composing most of the material universe, now widely thought to be some form of massive exotic particle. An intriguing alternative view is that dark matter is made of black holes formed during the first second of our universe's existence, known as primordial black holes. Now a scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, suggests that this interpretation aligns with our knowledge of cosmic infrared and X-ray background glows and may explain the unexpectedly high masses of merging black holes detected last year.

"This study is an effort to bring together a broad set of ideas and observations to test how well they fit, and the fit is surprisingly good," said Alexander Kashlinsky, an astrophysicist at NASA Goddard. "If this is correct, then all galaxies, including our own, are embedded within a vast sphere of black holes each about 30 times the sun's mass."

In 2005, Kashlinsky led a team of astronomers using NASA's Spitzer Space Telescope to explore the background glow of infrared light in one part of the sky. The researchers reported excessive patchiness in the glow and concluded it was likely caused by the aggregate light of the first sources to illuminate the universe more than 13 billion years ago. Follow-up studies confirmed that this cosmic infrared background (CIB) showed similar unexpected structure in other parts of the sky.

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To do so, they looked to a second black hole orbiting the first

By Caleb Scharf on May 1, 2016

Black holes may be massive, but they are also extraordinarily compact. That combination of properties makes them challenging regions to evaluate across vast cosmic distances. To learn more about these objects' physical properties, astronomers must therefore come up with measuring tricks. An international team of astronomers recently invented a new one: in the Astrophysical Journal Letters, the members report how to determine a black hole's spin using the interactions of two giant holes bound in mutual orbit.

OJ 287, a binary supermassive black hole system, sits about 3.5 billion light-years from Earth. The duo's primary black hole weighs in at an estimated 18 billion solar masses; the second is a mere 150 million solar masses. Because of this dramatic inequality in size, the smaller hole follows an orbit that punches through a disk of superheated matter swirling around the larger hole. These “outburst” events always occur within a 12-year orbit and are read by astronomers as changes in the system's visible light, which is for the most part produced by the superheated material.

Link of the article : http://arxiv.org/abs/1603.04171

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• Hawking's theory couldn't be proven, as it didn't relate effects of radiation
• Most believed impossible for information to hide while black hole shrunk
• Two separate groups of researchers have evidence to back up these claims
• These discoveries could help win the physicist the Nobel Prizε

For forty years ago, Stephen Hawking famously announced black holes evaporate and shrink because they emit radiation.
This so-called 'Hawking radiation' was a revolutionary theory, but due to the fragile nature of the escaping radiation, has been difficult to prove.

Now, two separate groups of researchers have discovered evidence to back up Hawking's claims - and their discoveries could finally help win the eminent physicist a Nobel Prize.

There has been a long standing belief that when a black hole dies, everything inside is destroyed.
Hawking's theory states that black holes should have the ability to thermally create and emit sub-atomic particles until they are completely depleted of their energy, known as Hawking radiation.

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06 April 2016

Astronomers have uncovered one of the biggest supermassive black holes, with the mass of 17 billion Suns, in an unlikely place: the centre of a galaxy that lies in a quiet backwater of the Universe. The observations, made with the NASA/ESA Hubble Space Telescope and the Gemini Telescope in Hawaii, indicate that these monster objects may be more common than once thought. The results of this study are released in the journal Nature.

Until now, the biggest supermassive black holes – those having more than 10 billion times the mass of our Sun – have only been found at the cores of very large galaxies in the centres of massive galaxy clusters. Now, an international team of astronomers using the NASA/ESA Hubble Space Telescope has discovered a supersized black hole with a mass of 17 billion Suns in the centre of the rather isolated galaxy NGC 1600.
NGC 1600 is an elliptical galaxy which is located not in a cluster of galaxies, but in a small group of about twenty. The group is located 200 million light-years away in the constellation Eridanus. While finding a gigantic supermassive black hole in a massive galaxy within a cluster of galaxies is to be expected, finding one in an average-sized galaxy group like the one surrounding NGC 1600 is much more surprising.
"Even though we already had hints that the galaxy might host an extreme object in the centre, we were surprised that the black hole in NGC 1600 is ten times more massive than predicted by the mass of the galaxy," explains lead author of the study Jens Thomas from the Max Planck-Institute for Extraterrestrial Physics, Germany.

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NASA, ESA, D. Coe, G. Bacon (STScI)
A black hole, visualized here in the M60-UCD1 galaxy, was thought to lose information as it disappears.

Some welcome his latest report as a fresh way to solve a black-hole conundrum; others are unsure of its merits.

Davide Castelvecchi
27 January 2016

Almost a month after Stephen Hawking and his colleagues posted a paper about black holes online1, physicists still cannot agree on what it means.

Some support the preprint’s claim — that it provides a promising way to tackle a conundrum known as the black hole information paradox, which Hawking identified more than 40 years ago. “I think there is a general sense of excitement that we have a new way of looking at things that may get us out of the logjam,” says Andrew Strominger, a physicist at Harvard University in Cambridge, Massachusetts, and a co-author of the latest paper.

Strominger presented the results on 18 January at a crowded talk at the University of Cambridge, UK, where Hawking is based.

Others are not so sure that the approach can solve the paradox, although some say that the work illuminates various problems in physics. In the mid-1970s, Hawking discovered that black holes are not truly black, and in fact emit some radiation2. According to quantum physics, pairs of particles must appear out of quantum fluctuations just outside the event horizon — the black hole’s point of no return. Some of these particles escape the pull of the black hole but take a portion of its mass with them, causing the black hole to slowly shrink and eventually disappear.

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Successful commissioning of GRAVITY at the VLTI
13 January 2016

Zooming in on black holes is the main mission for the newly installed instrument GRAVITY at ESO’s Very Large Telescope in Chile. During its first observations, GRAVITY successfully combined starlight using all four Auxiliary Telescopes. The large team of European astronomers and engineers, led by the Max Planck Institute for Extraterrestrial Physics in Garching, who designed and built GRAVITY, are thrilled with the performance. During these initial tests, the instrument has already achieved a number of notable firsts. This is the most powerful VLT Interferometer instrument yet installed.

The GRAVITY instrument combines the light from multiple telescopes to form a virtual telescope up to 200 metres across, using a technique called interferometry. This enables the astronomers to detect much finer detail in astronomical objects than is possible with a single telescope.

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Black holes such as the one depicted in Interstellar (2014) can be connected by wormholes, which might have quantum origins.

Many physicists believe that entanglement is the essence of quantum weirdness — and some now suspect that it may also be the essence of space-time geometry.

Ron Cowen

16 November 2015

In early 2009, determined to make the most of his first sabbatical from teaching, Mark Van Raamsdonk decided to tackle one of the deepest mysteries in physics: the relationship between quantum mechanics and gravity. After a year of work and consultation with colleagues, he submitted a paper on the topic to the Journal of High Energy Physics.

In April 2010, the journal sent him a rejection — with a referee’s report implying that Van Raamsdonk, a physicist at the University of British Columbia in Vancouver, was a crackpot.

His next submission, to General Relativity and Gravitation, fared little better: the referee’s report was scathing, and the journal’s editor asked for a complete rewrite.

But by then, Van Raamsdonk had entered a shorter version of the paper into a prestigious annual essay contest run by the Gravity Research Foundation in Wellesley, Massachusetts. Not only did he win first prize, but he also got to savour a particularly satisfying irony: the honour included guaranteed publication in General Relativity and Gravitation. The journal published the shorter essay1 in June 2010.

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An illustration of two black holes orbiting one another. The black hole in the center of the image is starved of gas by the black hole at the left, making the gas cloud of the black hole on the left brighter.ILLUSTRATION BY ZOLTAN HAIMAN, ADAPTED FROM FARRIS ET AL. 2014

By DENNIS OVERBYE
SEPTEMBER 16, 2015
The apocalypse is still on, apparently — at least in a galaxy about 3.5 billion light-years from here.

Last winter a team of Caltech astronomers reported that a pair of supermassive black holes appeared to be spiraling together toward a cataclysmic collision that could bring down the curtains in that galaxy.

The evidence was a rhythmic flickering from the galaxy’s nucleus, a quasar known as PG 1302-102, which Matthew Graham and his colleagues interpreted as the fatal mating dance of a pair of black holes with a total mass of more than a billion suns. Their merger, the astronomers calculated, could release as much energy as 100 million supernova explosions, mostly in the form of violent ripples in space-time known as gravitational waves that would blow the stars out of that hapless galaxy like leaves off a roof.

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ABOUT THIS IMAGE:
This artistic illustration is of a binary black hole found in the center of the nearest quasar host galaxy to Earth, Markarian 231. Like a pair of whirling skaters, the black-hole duo generates tremendous amounts of energy that makes the core of the host galaxy outshine the glow of the galaxy's population of billions of stars. Quasars have the most luminous cores of active galaxies and are often fueled by galaxy collisions.

Hubble observations of the ultraviolet light emitted from the nucleus of the galaxy were used to deduce the geometry of the disk, and astronomers were surprised to see light diminishing close to the central black hole. They deduced that a smaller companion black hole has cleared out a donut hole in the accretion disk, and the smaller black hole has its own mini-disk with an ultraviolet glow.

Astronomers using NASA's Hubble Space Telescope have found that Markarian 231 (Mrk 231), the nearest galaxy to Earth that hosts a quasar, is powered by two central black holes furiously whirling about each other.

The finding suggests that quasars — the brilliant cores of active galaxies — may commonly host two central supermassive black holes that fall into orbit about one another as a result of the merger between two galaxies. Like a pair of whirling skaters, the black-hole duo generates tremendous amounts of energy that makes the core of the host galaxy outshine the glow of the galaxy's population of billions of stars, which scientists then identify as quasars.

Scientists looked at Hubble archival observations of ultraviolet radiation emitted from the center of Mrk 231 to discover what they describe as "extreme and surprising properties."

If only one black hole were present in the center of the quasar, the whole accretion disk made of surrounding hot gas would glow in ultraviolet rays. Instead, the ultraviolet glow of the dusty disk abruptly drops off towards the center. This provides observational evidence that the disk has a big donut hole encircling the central black hole. The best explanation for the observational data, based on dynamical models, is that the center of the disk is carved out by the action of two black holes orbiting each other. The second, smaller black hole orbits in the inner edge of the accretion disk, and has its own mini-disk with an ultraviolet glow.

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RECORDED IN LIGHT A ring of light surrounds the boundary of a black hole in this artist illustration. Stephen Hawking theorizes that light on this boundary encodes information about everything that falls into the black hole.

Light sliding along the outside of a black hole is the key to understanding what’s inside, Stephen Hawking says.

The proposal from the world’s most famous living physicist, presented August 25 at a conference in Stockholm, is the latest attempt to explain what happens to information that falls into the abyss of a black hole. Losing that information would violate a key principle of quantum mechanics, leading to what’s known as the information paradox.

Hawking and two collaborators claim that the contents of a black hole are inventoried on a hologram on its boundary, the event horizon. Unlike previous descriptions of this hologram, the researchers say, their proposal lays out a specific mechanism for storing information that applies to every black hole in the universe. “This resolves the information paradox,” Hawking said in his presentation at the Hawking Radiation conference at the KTH Royal Institute of Technology.

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So I’m at this black hole conference in Stockholm, and at his public lecture yesterday evening, Stephen Hawking announced that he has figured out how information escapes from black holes, and he will tell us today at the conference at 11am.

As your blogger at location I feel a certain duty to leak information ;)

Extrapolating from the previous paper and some rumors, it’s something with AdS/CFT and work with Andrew Strominger, so likely to have some strings attached.

30 minutes to 11, and the press has arrived. They're clustering in my back, so they're going to watch me type away, fun.

10 minutes to 11, some more information emerges. There's a third person involved in this work, besides Andrew Strominger also Malcom Perry who is sitting in the row in front of me. They started their collaboration at a workshop in Hereforshire Easter 2015.

10 past 11. The Awaited is late. We're told it will be another 10 minutes.

11 past 11. Here he comes.

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Smoothed SDSS image of RGG 118, home of the smallest black hole ever observed in a galactic nucleus. The inset shows the Chandra identification of an x-ray source at the center. Credit: Baldassare et al. 2015
A team of astronomers have reported the detection of the smallest black hole (BH) ever observed in a galactic nucleus. The BH is hosted in the center of dwarf galaxy RGG 118, and it weighs in at 50,000 solar masses, according to observations made by Vivienne Baldassare of University of Michigan and her collaborators.

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Alternative gravity theories would result in “bumpy black holes,” which might be identifiable in x-ray observations.

Just before being gobbled up by a black hole, in-falling matter may emit an x-ray signal that could tell us about the black hole’s gravitational field. That’s the assumption of a new theoretical study of matter-accretion disks that form around black holes. The researchers show that alternative gravity models—characterized by “bumps” in the spacetime fabric around the black hole—produce slightly different x-ray emission from the disks. But identifying this signal will be challenging.

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Particle swarm. In Schnittman’s simulation, dark matter particles (shown with gray and pink trails) orbiting a rotating black hole (central sphere) could occasionally gain a large amount of energy and escape. The blue region (the ergosphere) is where the black hole’s rotation pulls spacetime along.

Particles orbiting near a spinning black hole might collide and get ejected with much more energy than previous calculations showed.

Black holes are mostly takers, not givers, but collisions among matter around a spinning black hole can result in high-energy particles that emerge with some of the black hole’s energy. Decades-old calculations showing only a modest energy gain for such particles are now contradicted by new results from two theoretical efforts showing that a particle can take away more than 10 times the energy that was put in. There are still questions about the feasibility of such collisions, but they might help astrophysicists understand some unexplained observations, such as an excess of gamma rays from the galactic center or ultrahigh-energy cosmic rays.

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