Black Holes

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Black holes may merge with light of a trillion suns

Two small black holes merge near third supermassive black hole.

When black holes collide, the ensuing cosmic drama was assumed to play out under the cloak of darkness, given that both objects are invisible. But now astronomers believe they have made the first optical observations of such a merger, marked by a blaze of light a trillion times brighter than the sun.

The flare was linked to a known black hole merger detected last year by the gravitational wave observatory, Ligo, which picked up ripples sent out through the fabric of space. The latest observations suggest that when these cataclysmic events occur within the accretion disk of an even more gigantic black hole, they are brilliantly illuminated by the surrounding dust and gas, making them also visible to optical telescopes.

Closer analysis suggested the merger had taken place in the vicinity of a distant supermassive black hole called J1249+3449, with a diameter equivalent to Earth’s orbit around the sun. The pair of smaller black holes sat at the outer reaches of the accretion disk, a halo of stars, dust and gas swirling around the vast central sinkhole. “These objects swarm like angry bees around the monstrous queen bee at the centre,” said Ford.

As the pair of black holes, each around the size of the Isle of Wight and with a combined mass of 150 suns, spiral inwards and coalesce, gravitational waves are sent out across space and the new, merged object experiences a kick in the opposite direction, sending it ploughing through the dust and gas of the disk and out into surrounding space.

If confirmed, the observations could help to resolve a central problem in black hole astronomy: that there are far more heavyweight black holes than there ought to be. Black holes form from collapsed ancient stars. Bigger black holes form when these merge, but some black holes are so big that in theory it ought to have taken longer than the age of the universe for them to snowball to their observed size.
 

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Hmm; let's see.

If there are hundreds of billions of galaxies out there, and most of them have black holes, and if these black holes have formed from several mergers, and if the Universe is thirteen billion years old, then there should be dozens of brilliant merger events visible each year - possibly more, depending how many it takes to build up a big black hole.

I'm not sure, but I don't think there are. Maybe galactic black holes are primordial- formed in the Big Bang, before the Universe was transparent.
 

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Hmm; let's see.

If there are hundreds of billions of galaxies out there, and most of them have black holes, and if these black holes have formed from several mergers, and if the Universe is thirteen billion years old, then there should be dozens of brilliant merger events visible each year - possibly more, depending how many it takes to build up a big black hole.

I'm not sure, but I don't think there are. Maybe galactic black holes are primordial- formed in the Big Bang, before the Universe was transparent.
Could the light may be shot out in the direction of the ionized jets along the axis of spin, so there could be a super-bright light emission in a laser-like pulse. Would we see that if it wasn't pointed directly at us?
 

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Good point. I'll ask a few astronomers who deal with this sort of stuff on a regular basis.
 

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Further, from this article in phsics.org

A gravitational wave event was picked up in May 2019 via LIGO/Virgo & to test their hypothesis, the team looked in archived data from

California-based Zwicky Transient Facility (ZTF), which identifies objects in the sky that rapidly change in brightness at visible wavelengths. They compared the ZTF catalog with 21 alerts put out by the LIGO/Virgo collaboration in 2019. Each of these alerts notifies astronomers about a potential gravitational-wave signal, including the source’s approximate coordinates. Through their analysis, Graham and his colleagues found a quasar flare that appeared in the same sky region as the 21 May candidate merger but delayed by 35 days. Quasars are known to vary in brightness, but the team showed that the observed flaring was inconsistent with past variations seen in this particular quasar’s emission. Graham and his colleagues also ruled out other possible explanations for the flaring, such as a supernova.

The team’s model explains this brightening as a merger of two black holes within the quasar accretion disk. According to the model, the resulting black hole shot out of the collision at high speed, creating a shock front that heated the gas along its path. The flare was delayed by several weeks relative to the gravitational-wave signal because the light was slowed by scattering in the opaque disk. At some point, the fast-moving black hole escaped the disk, which would explain why the flare ended after about 40 days.

The researchers predict that the black hole will orbit around the quasar’s central supermassive black hole and come crashing back into the disk approximately 1.6 years after the merger. Such a crash would reignite the flaring, which is why Graham and company plan to keep their eyes on this quasar for the next few years.

Astrophysicist Zoltan Haiman from Columbia University in New York says that the result is very significant if it can be confirmed. There are still some uncertainties, he says, such as whether a black hole merger could create a bright flare “before blowing the nearby gas to smithereens.” But if the quasar flares again within a year or so, as predicted, Haiman would have even more confidence in the model.
 

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During lockdown I have been doing some physics with Leonard Susskind on YouTube. For anyone interested in the physics, I can't recommend him enough. It will help if you have a maths background, but some of it is explained in layman's terms too. I raise this as Susskind is one of the few people to defeat Stephen Hawking in an argument on the subject during the classic Black Hole wars. Susskind's lectures will get you up to speed on Black Holes if you want to watch him. He's a bit of a national treasure imo.

Black holes and complexity

What lies behind the event horizon?

Black Holes and the Holographic Principle

The Black Hole Wars

See what YouTube lectures Stanford University has on offer
 

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What would happen if a black hole fell into a wormhole?

If wormholes exist, scientists may one day spot black holes falling into them, a new study suggests.

By Charles Q. Choi - Live Science Contributor
4 days ago
www.livescience.com

Astronomers think they might be able to detect black holes falling into wormholes using ripples in spacetime known as gravitational waves, but only if wormholes actually exist and such a scenario ever happened, a new study finds.

According to Einstein, who first predicted the existence of gravitational waves in 1916, gravity results from the way in which mass warps space and time. When two or more objects move within a gravitational field, they produce gravitational waves that travel at the speed of light, stretching and squeezing space-time along the way.

Gravitational waves are extraordinarily difficult to detect because they are extremely weak, and even Einstein was uncertain whether they really existed and if they would get discovered. After decades of work, scientists reported the first direct evidence of gravitational waves in 2016, detected using the Laser Interferometer Gravitational-Wave Observatory (LIGO).

Gravitational-wave observatories have detected more than 20 giant collisions between extraordinarily dense and massive objects such as black holes and neutron stars. However, more exotic objects may theoretically exist, such as wormholes, the collisions of which should also produce gravitational signals that scientists could detect.

Wormholes are tunnels in spacetime that, in theory, can allow travel anywhere in space and time, or even into another universe. Einstein's theory of general relativity allows for the possibility of wormholes, although whether they really exist is another matter.

[...]

https://www.livescience.com/what-if-black-hole-falls-into-wormhole.html
 

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Black holes: Cosmic signal rattles Earth after 7 billion years

By Jonathan Amos
BBC Science Correspondent
6 hours ago

Imagine the energy of eight Suns released in an instant.

This is the gravitational "shockwave" that spread out from the biggest merger yet observed between two black holes.

The signal from this event travelled for some seven billion years to reach Earth but was still sufficiently strong to rattle laser detectors in the US and Italy in May last year.

Researchers say the colliding black holes produced a single entity with a mass 142 times that of our Sun.

This is noteworthy. Science has long traced the presence of black holes on the sky that are quite a bit smaller or even very much larger. But this new observation inaugurates a novel class of so-called intermediate-sized black holes in the range of 100-1,000 Sun (or solar) masses.

[...]

https://www.bbc.co.uk/news/science-environment-53993937
 

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“Galaxy-Sized Big Bang” –Largest Black Holes in Observable Universe May Be Source of Dark Matter

Source: dailygalaxy.com
Date: 19 September, 2020

Albert Einstein described black holes as “the most perfect macroscopic objects there are in the universe: the only elements in their construction are our concepts of space and time,” which has inspired astrophysicists to question how big these paradoxical objects, these “Gates of Hell” might become?

A team of scientists now suggest that these behemoths lurking at the centers of galaxies could reach “stupendously large” sizes–where the higher their mass, the greater their power–“they would be like a mini, galaxy-sized Big Bang,” according to Julie Hlavacek-Larrondo, at Université de Montréal, who holds the Canada Research Chair in Observational Astrophysics of Black Holes. These enigmatic objects, as affirmed by quantum theory, could be incredibly complex and concentrate an enormous amount of information inside themselves –the largest hard disk that exists in nature, in two dimensions.

Discovering such gargantuan black holes may shed light on the nature of a significant fraction of the mysterious dark matter. These “stupendously large black holes” (SLABs) in galactic nuclei, exist in theory and may have been seeded by primordial black holes, suggests Florian Kuhnel who holds the Chair on Cosmology at the Arnold Sommerfeld Center for Theoretical Physics.

[...]

https://dailygalaxy.com/2020/09/stu...may-be-source-of-dark-matter-weekend-feature/
 

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A mini fractal universe may lie inside charged black holes (if they exist)

Source: livescience.com
Date: 9 October, 2020

Black holes are perhaps the strangest, least-understood objects in our universe. With so much potential — being linked to everything from wormholes to new baby universes — they have sucked in physicists for decades.

But as strange as these known objects are, even stranger types of black holes could be dreamed up. In one upside-down, hypothetical version of the universe, a bizarre type of black hole could exist that is stranger than an M.C. Escher sketch. Now, a team of researchers has plunged into the mathematical heart of so-called charged black holes and found a slew of surprises, including an inferno of space-time and an exotic fractal landscape … and potentially more.

[...]

https://www.livescience.com/amp/bizarre-charged-black-holes.html
 

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The Most Famous Paradox in Physics Nears Its End

Source: Quanta Magazine
Date: 29 October, 2020

In a landmark series of calculations, physicists have proved that black holes can shed information, which seems impossible by definition. The work appears to resolve a paradox that Stephen Hawking first described five decades ago.

In a series of breakthrough papers, theoretical physicists have come tantalizingly close to resolving the black hole information paradox that has entranced and bedeviled them for nearly 50 years. Information, they now say with confidence, does escape a black hole. If you jump into one, you will not be gone for good. Particle by particle, the information needed to reconstitute your body will reemerge. Most physicists have long assumed it would; that was the upshot of string theory, their leading candidate for a unified theory of nature. But the new calculations, though inspired by string theory, stand on their own, with nary a string in sight. Information gets out through the workings of gravity itself — just ordinary gravity with a single layer of quantum effects.

[...]

https://www.quantamagazine.org/the-black-hole-information-paradox-comes-to-an-end-20201029/
 

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The Most Famous Paradox in Physics Nears Its End
This is possibly the most fascinating and actually perceptible article I have read in relation to our enigma.

Whilst, like @WeeScottishLassie, I profess mainly bewilderment regarding such matters, two points emerge therein which are reassuring:

"Information, they now say with confidence, does escape a black hole. If you jump into one, you will not be gone for good. Particle by particle, the information needed to reconstitute your body will reemerge" .

"Theorists still haven’t mapped the step-by-step process whereby information gets out. “We now can compute the Page curve, and I don’t know why,” said Raphael Bousso at Berkeley. To astronauts who ask whether they can get out of a black hole, physicists can answer, “Sure!” But if the astronauts ask how to do it, the disquieting reply will be: “No clue.”.

Or at least I think so...! :rup:
 

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Astronomers Discover Binary Black Holes That Have Their Own 'Electron'

Source: sciencealert.com
Date: 14 November, 2020

Black holes are notable for many things, especially their simplicity. They're just … holes. That are 'black.' This simplicity allows us to draw surprising parallels between black holes and other branches of physics.

For example, a team of researchers has shown that a special kind of particle can exist around a pair of black holes in a similar way as an electron can exist around a pair of hydrogen atoms – the first example of a "gravitational molecule."

This strange object may give us hints to the identity of dark matter and the ultimate nature of space-time.

To understand how the new research, which was published in September to the preprint database arXiv, explains the existence of a gravitational molecule, we first need to explore one of the most fundamental – and yet sadly almost never talked about – aspects of modern physics: the field.

A field is a mathematical tool that tells you what you might expect to find as you travel from place to place in the universe.

[...]

https://www.sciencealert.com/astron...ole-system-that-looks-weirdly-like-a-molecule
 

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World's largest atom smasher could seed microscopic black holes

Source: livescience.com
Date: 4 December, 2020

The cosmos may be studded with black holes so tiny they could slip in between atoms, a wild new theory suggests.

And we could be making these teensy singularities all the time at the world's largest atom smasher, a new study shows. If we could make these objects, they could be a window into the mysterious nature of gravity.

We have four fundamental forces of nature (at least, that we know about so far): electromagnetism, strong force, weak force and gravity. All four forces operate at different ranges, have different carriers and interact in different ways. They also have very different strengths.

And no matter how you slice it, gravity always comes out the weakest. Gravity is such a feeble force that if it were a billion billion times stronger than it currently is, it would still be the weakest force by a factor of about 10 million.

Go ahead and lift whatever device you're reading on above your head. Congratulations. The muscles in your arm temporarily overcame the gravitational pull of the entire planet Earth.

Gravity is so laughably weak that physicists have started to wonder why. After all, something that strange, that odd, that out-of-place is practically begging for an explanation.

[...]

https://www.livescience.com/atom-smasher-could-seed-tiny-black-holes.html
 

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There should be a maximally huge supermassive black hole in the core of galaxy cluster Abell 2261, but none of the expected evidence for its existence can be found.
Somehow, a Monstrous Supermassive Black Hole Has Gone Missing

The Universe is full of galaxy clusters, but Abell 2261 is in a class of its own. In the galaxy in the centre of the cluster, where there should be one of the biggest supermassive black holes in the Universe, astronomers have been able to find no trace of such an object.

And a new search has only made the absence more puzzling: if the supermassive black hole got yeeted out into space, it should have left evidence of its passage. But there's no sign of it in the material surrounding the galactic centre, either. ...

FULL STORY: https://www.sciencealert.com/somehow-a-colossal-supermassive-black-hole-is-missing-in-action
 

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There should be a maximally huge supermassive black hole in the core of galaxy cluster Abell 2261...
It's one thing losing teaspoons, but...

"... even among BCGs, Abell 2261's BCG (named, in fact, A2261-BCG, and located about 2.7 billion light-years away) stands out. It's about a million light-years across - up to to 10 times the size of the Milky Way galaxy - and it has a huge, puffy core 10,000 light-years across, the largest galactic core ever seen".

The scale of this is just ridiculously impossible to take in!

An extraordinary story and once again illustrates how much science can now actually envisage, even if the explanation might be a mystery at present.

"We know, now, thanks to gravitational wave astronomy, that merging supermassive black holes send gravitational waves rippling across space-time. It's possible that, if the gravitational waves were stronger in one direction, then the gravitational recoil could kick the merged black hole in the opposite direction.

Finding evidence of this would be amazing".

A compelling read, even if I don't understand half of it. :atom:
 

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Cygnus X-1 black hole 50% more massive than previously thought

making it the heaviest stellar-mass black hole ever observed directly.

Based on new observations, an international team of researchers estimate the black hole is 21 times the mass of our sun and spinning faster than any other known black hole.

In the new study, researchers estimated the mass of Cygnus X-1 using a tried-and-tested method of measuring the distances of stars from Earth, called parallax. As Earth orbits the sun, astronomers measure the visible movement of stars relative to the background of more distant stars, and with a bit of trigonometry, they can use that movement to calculate the star's distance from Earth.

In addition, Cygnus X-1's black hole is slowly devouring its bright blue companion star by sucking in that star's outer layers, forming a bright disk rotating around the black hole. As the matter falls into the black hole, it gets heated to millions of degrees and emits brilliant X-ray radiation. Some of this matter narrowly escapes the black hole and is spit out in powerful jets emitting radio waves detectable on Earth.

They found that Cygnus X-1 is around 7,200 light-years from Earth, surpassing the previous estimate of 6,000 light-years. The updated distance suggests the blue supergiant companion star is brighter and more massive than previously thought, at 40 times more massive than our sun. And given the orbital period of the black hole, they were able to give a new estimate for the black hole's mass — a whopping 21 solar masses.

"Using the updated measurements for the black hole's mass and its distance away from Earth, we were able to confirm that Cygnus X-1 is spinning incredibly quickly — very close to the speed of light and faster than any other black hole found to date,"
 

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Lab-grown black hole analog behaves just like Stephen Hawking said it would

Article: 2 March, 2021

In 1974, Stephen Hawking theorized that the universe's darkest gravitational behemoths, black holes, were not the pitch-black star swallowers astronomers imagined, but they spontaneously emitted light — a phenomenon now dubbed Hawking radiation.

The problem is, no astronomer has ever observed Hawking's mysterious radiation, and because it is predicted to be very dim, they may never will. Which is why scientists today are creating their own black holes.

Researchers at the Technion-Israel Institute of Technology did just that. They created a black hole analog out of a few thousand atoms. They were trying to confirm two of Hawking's most important predictions, that Hawking radiation arises from nothing and that it does not change in intensity over time, meaning it's stationary.

"A black hole is supposed to radiate like a black body, which is essentially a warm object that emits a constant infrared radiation," study co-author Jeff Steinhauer, an associate professor of physics at Technion-Israel Institute of Technology, told Phys.org. "Hawking suggested that black holes are just like regular stars, which radiate a certain type of radiation all the time, constantly. That's what we wanted to confirm in our study, and we did."

[...]

https://www.livescience.com/black-hole-analog-confirms-hawking.html
 

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Lab-grown black hole analog behaves just like Stephen Hawking said it would
From another related article:

"According to Hawking, black holes can spontaneously emit photons at the event horizon thanks to transient quantum fluctuations known as virtual particles. Despite their name, virtual particles are indeed real particles — it’s just that they pop in and out of existence for a fleeting time".

https://www.zmescience.com/science/...e-in-the-lab-confirm-stephen-hawkings-theory/

Of course I understand it all...

21d14032141044f170cedc8b8c0af213.jpg
 

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Lab-grown black hole analog behaves just like Stephen Hawking said it would

Article: 2 March, 2021

In 1974, Stephen Hawking theorized that the universe's darkest gravitational behemoths, black holes, were not the pitch-black star swallowers astronomers imagined, but they spontaneously emitted light — a phenomenon now dubbed Hawking radiation.

The problem is, no astronomer has ever observed Hawking's mysterious radiation, and because it is predicted to be very dim, they may never will. Which is why scientists today are creating their own black holes.

Researchers at the Technion-Israel Institute of Technology did just that. They created a black hole analog out of a few thousand atoms. They were trying to confirm two of Hawking's most important predictions, that Hawking radiation arises from nothing and that it does not change in intensity over time, meaning it's stationary.

"A black hole is supposed to radiate like a black body, which is essentially a warm object that emits a constant infrared radiation," study co-author Jeff Steinhauer, an associate professor of physics at Technion-Israel Institute of Technology, told Phys.org. "Hawking suggested that black holes are just like regular stars, which radiate a certain type of radiation all the time, constantly. That's what we wanted to confirm in our study, and we did."

[...]

https://www.livescience.com/black-hole-analog-confirms-hawking.html
That's insanely cool :D
 

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There's a lot of them about.

black_hole_sky_map_cover_600.jpg


This image may look like a fairly normal picture of the night sky, but what you're looking at is a lot more special than just glittering stars. Each of those white dots is an active supermassive black hole.

And each of those black holes is devouring material at the heart of a galaxy millions of light-years away - that's how they could be pinpointed at all.

What makes the above image so special is that it covers the ultra-low radio wavelengths, as detected by the LOw Frequency ARray (LOFAR) in Europe. This interferometric network consists of around 20,000 radio antennas, distributed throughout 52 locations across Europe.

Currently, LOFAR is the only radio telescope network capable of deep, high-resolution imaging at frequencies below 100 megahertz, offering a view of the sky like no other. This data release, covering four percent of the Northern sky, is the first for the network's ambitious plan to image the entire Northern sky in ultra-low-frequencies, the LOFAR LBA Sky Survey (LoLSS).

more at link.
 

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There's a lot of them about.

black_hole_sky_map_cover_600.jpg


This image may look like a fairly normal picture of the night sky, but what you're looking at is a lot more special than just glittering stars. Each of those white dots is an active supermassive black hole.

And each of those black holes is devouring material at the heart of a galaxy millions of light-years away - that's how they could be pinpointed at all.



more at link.
It's just so incredibly hard to comprehend! Mind blowing.
 

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There's a lot of them about.

black_hole_sky_map_cover_600.jpg


This image may look like a fairly normal picture of the night sky, but what you're looking at is a lot more special than just glittering stars. Each of those white dots is an active supermassive black hole.

And each of those black holes is devouring material at the heart of a galaxy millions of light-years away - that's how they could be pinpointed at all.



more at link.

Just think. That could be all the alien civilisations that attempted to make one.
 

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Astronomers find ‘Goldilocks’ black hole

Early black holes may seed their more massive cousins

cosmosmagazine.com
30, March 2021

Last year, scientists used gravitational waves to detect an elusive intermediate-mass black hole for the first time. Now, Australian astronomers have spotted another – this time using gamma-ray bursts.

Black holes are formed when massive stars reach the end of their lives and collapse under their own gravity. But they aren’t all the same – stellar mass black holes are small, just a few times the mass of our Sun, while supermassive black holes at the hearts of galaxy are enormous, with masses millions or even billions of times greater than our sun.

Intermediate mass black holes are the missing link between these two populations, thought to span between 100 and 100,000 solar masses. The black hole discovered in 2020 was 142 solar masses – while this newly discovered monster is on the other end of the scale, at approximately 55,000 solar masses.

The study, published in Nature Astronomy, describes detecting the black hole through a gamma-ray burst – a flash of high-energy light emitted when two distant stars collided. But the researchers observed not one but two of these bursts reaching their detectors, because the signal had been gravitationally lensed by a massive object somewhere between the collision and Earth. The object – the black hole – distorted space time, producing multiple images of the same event.

This discovery could help astronomers understand how supermassive black holes form and grow as large as they do.

(...)

https://cosmosmagazine.com/space/astrophysics/astronomers-find-goldilocks-black-hole/
 

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String theory solves mystery about how particles behave outside a black hole photon sphere

phys.org
30 March, 2021

A paper by the Kavli Institute for the Physics and Mathematics of the Universe (Kavli IPMU) Director Ooguri Hirosi and Project Researcher Matthew Dodelson on the string theoretical effects outside the black hole photon sphere has been selected for the "Editors' Suggestion of the journal Physical Review D. Their paper was published on March 24, 2021.

In a quantum theory of point particles, a fundamental quantity is the correlation function, which measures the probability for a particle to propagate from one point to another. The correlation function develops singularities when the two points are connected by light-like trajectories. In a flat spacetime, there is such a unique trajectory, but when spacetime is curved, there can be many light-like trajectories connecting two points. This is a result of gravitational lensing, which describes the effect of curved geometry on the propagation of light.

In the case of a black hole spacetime, there are light-like trajectories winding around the black hole several times, resulting in a black hole photon sphere, as seen in the recent images by the Event Horizon Telescope (EHT) of the supermassive black hole at the center of the galaxy M87.

Released on April 10, 2019, the EHT Collaboration's images captured the shadow of a black hole and its photon sphere, the ring of light surrounding it. A photon sphere can occur in a region of a black hole where light entering in a horizontal direction can be forced by gravity to travel in various orbits. These orbits lead to singularities in the aforementioned correlation function.

However, there are cases when the singularities generated by trajectories winding around a black hole multiple times contradict with physical expectations. Dodelson and Ooguri have shown that such singularities are resolved in string theory.

(...)

https://phys.org/news/2021-03-theory-mystery-particles-black-hole.amp
 

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Can we solve the black hole information paradox with 'photon spheres'?

By Paul Sutter - Astrophysicist
livescience.com
19 July, 2021


Are black holes as simple as they appear, or is there more to their story?

Theories that attempt to resolve the so-called black hole information paradox predict that black holes are much more complicated than general relativity suggests. Future observations of photon spheres — swirling bands of light around the edges of black holes — will be able to test these theories.

According to Albert Einstein's theory of general relativity, black holes are surprisingly simple. If you know the mass, charge and spin of a black hole, you know everything there is to know about it. In fact, black holes are some of the simplest and most straightforward characters in the universe.

But that apparent simplicity gives rise to a troubling paradox. In the 1970s, famed astrophysicist Stephen Hawking realized that black holes aren't completely black. Instead, they emit radiation through a subtle quantum mechanical process operating at their event horizons, or the boundaries of black holes where nothing, not even light, can escape.

Because black holes are so simple and can be described with only three numbers, all the information about the material that falls into black holes is seemingly locked away forever. It doesn't matter if you build a black hole out of dead stars and interstellar dust or a black hole out of cats; as long as those two black holes have the same spin, mass and charge, they will be identical.

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https://www.livescience.com/black-hole-information-paradox-photon-spheres.html
 

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We Just Got an Image of a Plasma Jet From Another Supermassive Black Hole, And Whoa

By FIONA MACDONALD
sciencealert.com
19 July, 2021


Two years ago, the Event Horizon Telescope gave us the first breathtaking image of the supermassive black hole at the centre of the M87 galaxy.

Now, the same telescope has presented an unprecedentedly detailed view of a plasma jet being spat out by the supermassive black hole at the centre of the nearby Centaurus A galaxy.

This is a pretty huge announcement for a couple of reasons, so let's break it down.

First, the image is not only beautiful to look at but mind-boggling to consider – at an average distance of 12 million light-years away, the weirdly shaped Centaurus A galaxy is the closest radio-loud source to Earth. It's known for its black hole, which spits out powerful plasma jets that we can detect here on Earth.

In the new image, a jet is captured on less than a 'light-day' scale, showing us in never-before-seen detail what is happening in these plasma jets.

"Usually we see these jets ... at larger scales, and now we're really peering down into the center of the source," explains first author Michael Janssen from the Max-Planck-Institut für Radioastronomie, Bonn in Germany, in a video Q&A released alongside the paper.

"Centaurus A is the closest radio galaxy to Earth [and] was actually discovered as one of the first extragalactic radio sources. Because of that feedback we can resolve and see the outflow [of the jet] as it ploughs through the galaxy and what it does to the gas and how it may trigger star formation, which is a very broad research project."

Second, the high-resolution observations of the jet match what we'd expect to see based on general relativity – meaning once again, the Event Horizon Telescope's imaging shows Einstein was right.

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https://www.sciencealert.com/we-just-got-images-of-a-second-black-hole-spitting-out-plasma-jets
 
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