black holes

Record-Breaking Stellar Black Hole Found Lurking Close to Earth.

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An artist’s impression of the star’s orbit with the black hole. (ESO/L. Calçada)

You never really know what you might find hiding in your own backyard, especially if those things are particularly adept at escaping detection.

Just 1,924 light-years from the Solar System, in the constellation of Aquila, astronomers have just discovered a black hole.

And it’s not just any black hole. Named Gaia BH3, or BH3, the object is the most massive stellar-mass black hole we’ve ever spotted in the Milky Way, clocking in at a hefty 33 times the mass of the Sun.

It’s the second-closest black hole we’ve found to our homeworld, and it’s just hanging out, quietly in space, minding its own black hole business. The only reason we know it’s there is because it’s in a binary orbit with a companion star whose motion can’t be explained any other way.

To be clear, BH3 poses absolutely no threat. A black hole’s gravitational field is no stronger than that of a star of equivalent mass, and BH3 is just doing its own thing. But as the third dormant black hole discovered in Gaia data, it does raise the question about how many more of these beasts are out there, zooming around undetected.

BH3 compared with the closest (left) and the second most massive (middle) stellar black holes in the Milky Way. (ESO/M. Kornmesser)

“No one was expecting to find a high-mass black hole lurking nearby, undetected so far,” says astronomer Pasquale Panuzzo of the National Centre for Scientific Research (CNRS) in France, member of the Gaia collaboration, and first author on the paper describing the object.

“This is the kind of discovery you make once in your research life.”

Black holes broadly fall into different mass categories. There are supermassive ones that can be millions to billions of times the mass of the Sun; those are usually found at the centers of galaxies, and we’re not sure how they form.

The smaller, stellar-mass ones form from the collapse of stellar cores when massive stars go supernova. These can be up to about 65 times the mass of the Sun (although larger ones can form from mergers).

Estimates put the number of stellar-mass black holes in the Milky Way at up to 100 million, but they’re not very easy to detect, since black holes famously don’t emit any light.

We might occasionally spot a flare from one if it slurps down some material from a passing or binary companion star, since that process generates a lot of heat. Otherwise, they just hang about being dormant and invisible. We’ve only found around 20 so far, with a few more candidates.

There are a few ways we can detect dormant stellar-mass black holes, and one of them involves not the black hole itself but any stars in companion orbits, close enough to be gravitationally bound to the black hole but not close enough to be devoured. These stars will move around oddly in space, describing an orbit with something we cannot see.

This is where Gaia comes in. A spacecraft sharing Earth’s orbit around the Sun, Gaia has been operational since 2013. It maps the three-dimensional positions and motions of stars in the Milky Way with the highest precision yet. The more time it spends staring at the stars, the more precise its measurements become.

The fourth Gaia data release isn’t expected before the end of 2025, but the discovery of BH3 as astronomers checked the data was too exciting to sit on.

“We took the exceptional step of publishing this paper based on preliminary data ahead of the forthcoming Gaia release because of the unique nature of the discovery,” says astronomer Elisabetta Caffau of the CNRS.

An artist’s impression of the BH3 system. (ESO/L. Calçada)

What we know about the system is that the two objects are separated by a distance of about 16 times the distance between Earth and the Sun, and orbit each other every 11.6 years. The black hole clocks in at about 32.7 solar masses.

The star, by contrast, is small, clocking in at just 76 percent of the Sun’s mass, but nearly five times its size. It’s very poor in heavy elements, a property that means it must be very old, since stars didn’t incorporate these elements into their formation until previous generations of stars had produced them and sprayed them out into the Universe.

The star also shows no sign of pollution from the material that the black hole precursor must have ejected as it went supernova, suggesting that the two came together in their orbital dance after the black hole had already formed.

Stars with cores large enough to form a black hole nearly 33 times the Sun’s mass are challenging to explain. However, models suggest that this can be achieved if the massive precursor star also had low metallicity.

Hopefully, the discovery represents a teaser of what is to come. The researchers anticipate finding even more black holes upon the fourth release of Gaia data.

Webb’s “Astonishing Discovery” of Huge Black Holes in Early Universe – “Thought To Be Impossible”

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The transition in star formation rates and black hole growth as redshift decreases from regimes where positive feedback dominates to a later epoch when feedback is largely negative. Credit
Steven Burrows, Rosemary Wyse, and Mitch Begelman

The James Webb Space Telescope’s discovery of early galaxies with massive black holes challenges traditional galaxy formation theories, proposing a synchronous development of black holes and stars, a finding that could reshape our understanding of cosmic evolution.

Astronomers have long sought to understand the early universe, and thanks to the James Webb Space Telescope (JWST), a critical piece of the puzzle has emerged. The telescope’s infrared detecting “eyes” have spotted an array of small, red dots, identified as some of the earliest galaxies formed in the universe.

This surprising discovery is not just a visual marvel, it’s a clue that could unlock the secrets of how galaxies and their enigmatic black holes began their cosmic journey.

“The astonishing discovery from James Webb is that not only does the universe have these very compact and infrared bright objects, but they’re probably regions where huge black holes already exist,” explains JILA Fellow and University of Colorado Boulder astrophysics professor Mitch Begelman. “That was thought to be impossible.”

Begelman and a team of other astronomers, including Joe Silk, a professor of astronomy at Johns Hopkins University, published their findings in The Astrophysical Journal Letters, suggesting that new theories of galactic creation are needed to explain the existence of these huge black holes.

“Something new is needed to reconcile the theory of galaxy formation with the new data,” elaborates Silk, the lead author of the potentially groundbreaking study.

The Traditional Tale of Galaxy Formation

Astronomers had previously posited a somewhat orderly evolution when thinking about how galaxies formed. Conventional theories held that galaxies form gradually, assembling over billions of years. In this slow cosmic evolution, stars were thought to emerge first, lighting up the primordial darkness.

“The idea was that you went from this early generation of stars to the galaxies really becoming mainly dominated by stars,” adds Begelman. “Then, towards the end of this process, you start building these black holes.”

Supermassive black holes, those enigmatic and powerful entities, were believed to appear after the first stars, growing quietly in the galactic core. They were seen as regulators, occasionally bursting into action to temper the formation of new stars, thereby maintaining a galactic balance.

Challenging Conventional Wisdom

Thanks to the observations of the “little red dots” by the JWST, the researchers found that the first galaxies in the universe were brighter than expected, as many showed stars coexisting with central black holes known as quasars.

“Quasars are the most luminous objects in the universe,” explains Silk. “They are the products of gas accretion onto massive black holes in galaxy nuclei that generate immense luminosities, outshining their host galaxies. They are like monsters in the cuckoo’s nest.”

Seeing the coexistence of stars with black holes, the researchers quickly realized that the conventional theories of galaxy formation had to be flawed. “[This new data] looks like [the process is] reversed, that these black holes formed along with the first stars, and then the rest of the galaxy followed,” says Begelman. “We’re saying that the growth of the black hole, at first, promotes the stars. And only later, when conditions change, does it flip into a mode of turning off the stars.”

From this proposed new process, the researchers found that the relationship between star formation and black hole formation seemed closer than expected, as each initially amplified the growth of the other via a process known as positive feedback.

“Star formation accelerates massive black hole formation, and vice versa, in an inextricably connected interplay of violence, birth, and death that is the new beacon of galaxy formation,” says Silk.

Then, after almost a billion years, the nurturing giants became suppressive, depleting the gas reservoirs in their galaxies and quenching star formation. This “negative feedback” was due to energy-conserving outflows—powerful winds that drove gas out of the galaxies, starving them of the material needed to create new stars.

A New Galactic Timeline

Armed with the revelation of the black holes’ nurturing behavior, the researchers proposed a new timeline for the shift from positive to negative feedback in early galaxy formation. By looking at the different light spectra and chemical signatures emitted from these “little red dots,” the researchers suggested that this shift occurred around 13 billion years ago, one billion years after the Big Bang, a period astronomers classify as “z ≈6.”

Identifying this transition epoch helps astronomers target specific periods in the universe’s history for observation. It can guide future observational strategies using telescopes like JWST and others to study the early universe more effectively. Additionally, by understanding when this shift occurred, astronomers can better contextualize the characteristics of modern galaxies, including size, shape, star composition, and activity level.

Validating A Novel Process

To validate this new theory of collaborative galactic formation between the stars and black holes, and provide further insight into the processes involved, computer simulations are needed.

“This will take some time,” Begelman says. “The current computer simulations are rather primitive, and you need high resolution to understand everything. It takes a lot of computing power and is expensive.”

Until then, there are other steps the astronomy community can take to review and validate this new theory.

“The next steps will come from improved observations,” Silk adds. “The full power of JWST to study the spectra of the most distant galaxies will be unleashed over the next years.”

Both Begelman and Silk are optimistic about the rest of their field adopting their proposed idea.

“As far as I know, we’re the first to go in quite this extreme direction,” adds Begelman. “I was kind of pushing the envelope over the years with my collaborators working on this black hole formation problem. But JWST shows us that we didn’t think outside the box enough.”

‘Twisty’ new theory of gravity suggests information can escape black holes after all

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There’s a proverb in astronomy that goes something like, “black holes have no hair.” This indicates that black holes are extremely straightforward entities under the framework of general relativity. The only necessary characteristics of a black hole are its mass, electric charge, and spin rate. You now know everything there is to know about black holes just from those three numbers. That is to say, they are bare; they lack any further data.

This feature of black holes has been a major source of frustration for astronomers trying to figure out the inner workings of these cosmic behemoths. However, understanding black holes and their inner workings is impossible due to the absence of any kind of “hair” on their surfaces. Unfortunately, black holes continue to be among the universe’s most elusive and baffling features.

The present knowledge of general relativity, however, is essential to the “no-hair” black hole notion. The emphasis of this relativity illustration is on the curved nature of space-time. Any object with enough mass or energy to bend space-time around it will provide that object directions for movement.

However, this is not the only viable option for building a relativity theory. Space-time’s “twistiness,” as opposed to its curvature, is the subject of a whole distinct method. According to this interpretation, the presence of anything heavy or energetic causes localised distortions in space-time, which in turn direct the motion of nearby objects.

The two techniques, one based on curvature and the other based on twistiness, are mathematically equal. However, Einstein’s earlier development of the curvature-based language has led to its widespread use. There is a lot of possibility for interesting theoretical discoveries that aren’t clear in the curvature method in the twistiness approach, sometimes known as “teleparallel” gravity for its mathematical usage of parallel lines.

A group of theoretical physicists, for instance, has lately investigated how the concept of teleparallel gravity can tackle the “hairiness” of black holes. In July, they released a paper detailing their results on the arXiv preprint database. (The findings haven’t been examined by other scientists.)

Using a scalar field, a quantum phenomenon that exists in all of space and time, the group investigated possible additions to general relativity. The Higgs boson, which gives many particles their masses, is a well-known scalar field. Physicists have long employed scalar fields in attempts to explain the nature of cosmic mysteries like dark matter and dark energy, and it is possible that there are other scalar fields that inhabit the universe and subtly modify how gravity functions.

There is a finite number of ways to include scalar fields into general relativity based on regular curvature. In teleparallel gravity, though, you have a lot more leeway. Using the teleparallel framework, this research group found a technique to include scalar fields into general relativity. Then, scientists applied this method to see if these previously unseen scalar fields manifested themselves in the vicinity of black holes.

When seen via the teleparallel lens, the scalar fields introduced to general relativity end up giving black holes some facial hair.

The presence of a robust scalar field close to a black hole’s event horizon constitutes the “hair” in this context. This scalar field is crucial because it contains information about the black hole that might help scientists learn more about them without having to actually enter them.

Scientists have finally figured out how to give black holes hair, but now they need to address the observable repercussions of their findings. It’s possible that future measurements of gravitational waves will pick up on faint traces of these scalar fields when they manifest in black hole mergers, for instance.

Do Black Holes Die?

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Stephen Hawking’s suggestion that black holes “leak” radiation left physicists with a problem they have been attempting to solve for over 50 years.

Do black holes die? In what is arguably his most significant contribution to science, Stephen Hawking suggested that black holes can leak a form of radiation that causes them to gradually ebb away, and eventually end their lives in a massive explosive event.

This radiation ,  later called “Hawking radiation,” inadvertently causes a problem at the intersection of general relativity and quantum physics — the former being the best description we have of gravity and the universe on cosmically massive scales, while the latter is the most robust model of the physics that governs the very small.

The two theories have been confirmed repeatedly since their distinct inceptions at the start of the 20th century. Yet, they remain frustratingly incompatible.

This incompatibility , which mainly arises from the lack of a theory of “quantum gravity,” was compounded in the mid-1970s when Hawking took the principles of quantum physics and applied them to the edge of black holes. A paradox was born that physicists have been working to solve for over 50 years.

We may finally be on the verge of a solution thanks to review published in the journal Europhysics Letters in August 2022. In it, University of Sussex physics researchers Xavier Calmet and Stephen D. H. Hsu detail the problem of the so-called “Hawking paradox,”  and potential solutions to this cosmological problem.

What’s the Problem With Hawking Radiation?

In a 1974 letter entitled Black hole explosions? published in the journal Nature, a young Hawking proposed that quantum effects, usually ignored in black-hole physics, could become significant in the deterioration of mass of a black hole over a period of approximately 10¹⁷ (10 followed by 16 zeroes) seconds.

Black holes are created when massive stars reach the end of their lives and the fuel they use for nuclear fusion is exhausted. The cessation of nuclear fusion ends the outward pressure that supports a star against the inward force of its own gravity

This results in a core collapse that creates a point in which spacetime is infinitely curved — a central singularity that physics currently can’t explain. At the outer edge of this extreme curvature is the “event horizon” of the black hole, or the point at which not even light is fast enough to escape the gravitational pull of the black hole.

“Either we need to modify quantum mechanics or maybe Einstein’s theory of general relativity.”

“Hawking investigated quantum effects close to the horizon of black holes realizing that pairs of particles would be spontaneously generated here,” Calmet tells Popular Mechanics. “Looking at a specific pair of particles, he could show that one of the two when produced at the event horizon would fall into the black hole never to be seen again. The other would escape and be in principle visible to an outside observer. This is the famous Hawking radiation.”

When these so-called virtual particles arise, they do so with equal and opposite charges to avoid violating the law of conservation of energy, which states that energy can neither be created nor destroyed. Like a bank, the vacuum of space has an overdraft facility, but this debt is usually quickly paid back by the particles annihilating each other.

If one particle escapes as Hawking radiation and avoids annihilation, the energy debt that remains has to be paid by the mass of the black hole. This causes it to gradually evaporate as more particles pop into existence and more Hawking radiation is emitted, sapping more mass.

“Hawking radiation is thermal, and thermal radiation is pretty much featureless. This means that it cannot carry information about the object that emitted it,” Calmet says. “This would be a serious issue for black holes.”

He points out that Hawking’s calculation implies that the information about what went into the black hole would be destroyed as the black hole evaporates.

“If true, this would be an issue for physics as one of the key properties of quantum mechanics called ‘unitarity’ implies that it is always possible to watch a movie backward. In other words, from the observation of the radiation emitted by a black hole, quantum mechanics tells us that we should be able to reconstruct all the history of the black hole, what went into it,” Calmet says. “If Hawking is right, we would need to accept that one of the well-established theories of physics is wrong. Either we need to modify quantum mechanics or maybe Einstein’s theory of general relativity.”

Fortunately, just last year, the physicists suggested an idea that could do away with the Hawking paradox by using existing mechanisms.

Black Holes May Have Hair After All

Despite being a powerful and mysterious spacetime phenomenon, black holes are fairly easy to describe. This is because they can only have three properties that we are sure of: mass, angular momentum, and electric charge. Theoretical physicist John Wheeler summed this up with the phrase “black holes have no hair.”

Calmet and Hsu suggest that information carried by swallowed matter may be encoded in the gravitational field of a black hole. By calculating corrections to gravity on a quantum level, they showed the potential of the star is sensitive to its internal conditions. This means black holes possess, for lack of a better term, “quantum hair” grown by its progenitor star’s composition.

black hole created after supernova, illustration

Black hole created after supernova event.

“When this star collapses to a black hole, the correction remains and black holes thus have a quantum hair,” Calmet explains. “In other words, black holes have some quantum memory of their progenitor star.”

The duo followed this by suggesting that Hawking radiation isn’t entirely thermal in nature. Instead, they believe it has informational quantum hair encoded into it.

“The very small departures from thermality are enough to explain how the information that is in the black hole remains accessible to an outside observer,” Calmet argues. “This is enough to preserve unitarity and thus, there is no paradox.”

The beauty of Calmet and Hsu’s theory is it requires no adjustments to quantum mechanics or general relativity, or extra mechanisms not already proposed by physics.

“In the end, all the ingredients to solve the problem have been around for quite a while, in a sense Hawking could have solved it himself if he had looked for a simple explanation,” Calmet says. “It is striking to me that solving the information paradox could be done without positing new physics despite what most people have believed for almost five decades.”

Other ideas to solve Hawking’s paradox aren’t nearly as conservative. Indeed, some could change our fundamental concept of the universe–or should that be “universes?”

Do Black Holes Die?

black hole, artwork

The concept of the “multiverse” is the idea that multiple universes exist in addition to our own, but are separated and unable to interact. One new iteration of this idea suggests that the singularity at the heart of a black hole — the infinitely curved point at which all laws of physics break down — is actually a separate and distinct infant universe.

“In my theory, every black hole is actually a wormhole or an ‘Einstein-Rosen bridge’ to a new universe on the other side of the black hole’s event horizon,” Nikodem Poplawski, a physics lecturer in the Department of Mathematics and Physics at the University of New Haven, tells Popular Mechanics.

This would mean each universe, like our own, could host billions of black holes, each containing its own baby universe. Poplawski says that this proposition resolves Hawking’s paradox naturally.

“The information does not disappear but goes to the baby universe on the other side of the black hole’s event horizon,” Poplawski continues. “The matter and information that falls into a black hole and emerges from a white hole [the opposite of a black hole which allows exit but not entry] in the baby universe.

While the theory doesn’t explicitly account for Hawking radiation, much like Einstein’s original theory of general relativity, it doesn’t disallow it. With regard to the eventual evaporation of the black hole, Poplawski says this event would just permanently seal off the infant universe from its parent.

Many other ideas have been put forward to solve Hawking’s paradox, including information remaining in the black hole’s interior and emerging at the end of black hole evaporation. While none have quite wrapped the problem up in a neat bow, Calmet says some of the finest minds in physics are hard at work on the issue.

Hawking was a titan in his field, and his most significant work showed that not even cosmic titans like black holes can last forever—black holes really could die. Hawking’s successors are working to ensure this impermanence applies to the paradox that bears his name.

Bending light helps reveal one of the biggest black holes ever recorded

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An “ultramassive” black hole hundreds of millions of light years from Earth is one of the biggest on record, a new study reveals. It is 30 billion times the mass of our Sun, a scale rarely seen by astronomers.

The international team took advantage of a phenomenon known as gravitational lensing to spot the gigantic gravity well. The process occurs when galaxies warp the fabric of space, creating a natural “magnifying glass” that boosts light from distant background objects.

“This particular black hole, which is roughly 30 billion times the mass of our Sun, is one of the biggest ever detected and on the upper limit of how large we believe black holes can theoretically become, so it is an extremely exciting discovery,” says lead author Dr. James Nightingale from the Department of Physics at Durham University in a media release.

The effect provides an observation method to infer the presence of black holes and measure their size based on how significant the light bending is. Gravitational lensing opens the door to discovering far more black holes than previously thought, while also shedding light on how they grow so large.

“Most of the biggest black holes that we know about are in an active state, where matter pulled in close to the black hole heats up and releases energy in the form of light, X-rays, and other radiation,” Dr. Nightingale explains.

“However, gravitational lensing makes it possible to study inactive black holes, something not currently possible in distant galaxies. This approach could let us detect many more black holes beyond our local universe and reveal how these exotic objects evolved further back in cosmic time.”

YouTube video

The project began almost two decades ago when Durham astronomer Professor Alastair Edge noticed a giant arc of a gravitational lens when reviewing images of a galaxy survey. Dr. Nightingale and his colleagues’ discovery is based on a supercomputer’s simulations from extremely high-resolution images collected by NASA’s Hubble telescope.

Black holes with masses millions to billions of times greater than that of our own Sun sit at the center of nearly every galaxy. They are places in space where the pull of gravity is so strong that even light can’t escape it. This is what makes them invisible.

The team hopes this is the first step in enabling a deeper exploration of their mysteries. Future large-scale telescopes will help astronomers study even more distant black holes to learn more about their size and scale. The largest black hole in the known universe to date is 18.2 billion light years away. It has a mass equivalent to about 66 billion stars.

Listen to this eerie echo coming from Milky Way’s supermassive black hole

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 Scientists have detected a mysterious “echo” originating from the supermassive black hole at the center of the Milky Way. A team in France estimates that this eerie sound was made approximately 200 years ago, when the black hole stirred from a state of dormancy.

According to researchers with the National Center for Scientific Research (CNRS), this acoustic phenomenon signifies an intense period of activity in which our galaxy’s black hole consumed vast amounts of gas and dust. Particles were drawn towards the black hole’s event horizon, a point of no return from which even light cannot escape. As the massive black hole ingested this material, brilliant X-ray light bursts occurred, producing echoes that can be translated into sound waves here on Earth.

Dr. Frederic Marin, the corresponding author from Strasbourg University, explains that this discovery provides evidence of a past awakening of this gigantic entity – an object four million times more massive than the Sun. It sheds new light on the enigmatic and dynamic environment of supermassive black holes, which are incredibly dense regions at the centers of galaxies. These black holes exert a powerful gravitational pull, drawing in any surrounding gas and dust.

Sagittarius A* (Sgr A*), the supermassive black hole at the center of our own galaxy, is only 26,000 light-years away. Dr. Marin explains that their research reveals the missing evidence that X-rays from giant molecular clouds originate from the reflection of an intense but short-lived flare produced at or near Sgr A*. This discovery helps us understand the historical activity of our galaxy’s center.

Scroll down to hear what our galaxy’s black hole sounds like

image of a much wider view of the center of the Milky Way obtained by Chandra.
New data from NASA’s Imaging X-ray Polarimetry Explorer (IXPE) has provided evidence that the supermassive black hole at the center of the Milky Way Galaxy- known as Sagittarius A* (Sgr A*) – went through a very intense period of activity some 200 years ago after gobbling up gas and dust that came within its range. The IXPE data, which shows the echo of this past activity, can be seen in orange in the bottom image. It was combined with data from Chandra, another NASA X-ray observatory, seen in blue, which shows only direct light from the Galactic center. The top image is a much wider view of the center of the Milky Way obtained by Chandra. CREDIT © NASA/CXC/SAO/IXPE

One of the few black holes where matter flow can be observed, Sgr A* is challenging to study due to its absorption of all surrounding light. Scientists have spent decades looking for signs of black hole activity. To illustrate the black hole’s emergence from its dormant state, Dr. Marin likens it to a single glow-worm in a forest suddenly becoming as bright as the Sun.

The research also offers an explanation for the unusually bright galactic molecular clouds near Sgr A*, which are reflecting the X-rays emitted by the black hole two centuries ago. The international team integrated data from the IXPE (Imaging X-ray Polarimetry Explorer) space telescope and the Chandra X-ray Observatory to conduct their study.

Their findings suggest that the primary source of the emission is Sgr A*, as the polarization angle is consistent with this. The degree of polarization indicates that about 200 years ago, the X-ray luminosity of Sgr A* momentarily matched that of a Seyfert galaxy – a type of galaxy with an extremely active center producing strong radiation bursts.

Just as a compass points to its source, the polarized X-ray light emanates directly from Sgr A*. The scientists are now focusing on determining the physical mechanisms that enable a black hole to transition from a quiescent to an active state.

Black holes are formed when a dying star collapses under its own gravitational force, leading to a supernova, an extraordinarily powerful stellar explosion. These astronomical entities have such immense gravitational pull that even light cannot escape, rendering them invisible. Supermassive black holes, which can be billions of times larger than the Sun, are believed to be present at the center of all large galaxies.

Stephen Hawking’s unnerving theory confirmed: Everything in the universe will evaporate

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The late theoretical physicist, Stephen Hawking, is still showing his brilliance years after his death. Scientists have now confirmed one of Hawking’s more unnerving theories — stating that everything in the universe will eventually evaporate.

Scientists from Radboud University confirmed Stephen Hawking’s theory on black holes and their evaporation. Due to Hawking radiation, named for the famous scientist, black holes will eventually evaporate, but the event horizon is not as crucial to this as previously believed.The new study reveals that particles can be created and radiation can occur far beyond the event horizon. This means that not only black holes but also other large objects in the universe, like remnants of dead stars, will eventually cease to exist.

Combining quantum physics and Einstein’s theory of gravity, Hawking proposed that pairs of particles are spontaneously created near the event horizon of black holes, with one particle escaping while the other falls into the black hole. This process, which produces Hawking radiation, leads to the gradual evaporation of black holes over time.

black hole
This illustration depicts a star (in the foreground) experiencing spaghettification as it’s sucked in by a supermassive black hole (in the background) during a ‘tidal disruption event’. In a new study, done with the help of ESO’s Very Large Telescope and ESO’s New Technology Telescope, a team of astronomers found that when a black hole devours a star, it can launch a powerful blast of material outwards. (CREDIT: ESO/M. Kornmesser)

The researchers at revisited this phenomenon and explored the significance of the event horizon. Their interdisciplinary approach involving physics, astronomy, and mathematics investigated the creation of particle pairs in the vicinity of black holes. Surprisingly, they found that new particles can be created even beyond this specific point in space, challenging the previous understanding.

“We demonstrate that, in addition to the well-known Hawking radiation, there is also a new form of radiation,” says researcher Michael Wondrak in a media release.

“We show that far beyond a black hole the curvature of spacetime plays a big role in creating radiation. The particles are already separated there by the tidal forces of the gravitational field,” adds researcher Walter van Suijlekom.

“That means that objects without an event horizon, such as the remnants of dead stars and other large objects in the universe, also have this sort of radiation. And, after a very long period, that would lead to everything in the universe eventually evaporating, just like black holes. This changes not only our understanding of Hawking radiation but also our view of the universe and its future,” concludes Heino Falcke.

Who was Prof. Stephen Hawking?

Stephen Hawking was an English theoretical physicist, cosmologist, and author from Oxford in the United Kingdom. He is widely considered one of the greatest scientists of the 20th century.

Hawking was diagnosed with a rare, early-onset, slow-progressing form of motor neuron disease (also known as ALS or Lou Gehrig’s disease) that gradually paralyzed him over the decades. Despite his physical limitations, he continued to work and make significant contributions to the field of theoretical physics.

Stephen Hawking
Dr. Stephen Hawking, a professor of mathematics at the University of Cambridge, delivers a speech entitled “Why we should go into space” during a lecture that is part of a series honoring NASA’s 50th Anniversary, Monday, April 21, 2008, at George Washington University’s Morton Auditorium in Washington. Photo Credit: (NASA/Paul. E. Alers)

Hawking’s key scientific works revolved around the physics of black holes and the properties of the universe. He proposed that black holes are not completely black but emit small amounts of thermal energy — Hawking radiation.

In 1988, Hawking achieved international recognition with the publication of “A Brief History of Time.” The book aimed to present his theories about the universe so the general public could understand them. The book became a bestseller, making him a household name.

Hawking was a professor of mathematics at the University of Cambridge for three decades, until his retirement in 2009. He continued to work as a research director at the university until his death. Stephen Hawking passed away in March of 2018, but his influence continues to resonate in the fields of cosmology, general relativity, and quantum gravity, particularly among those studying black hole physics.

Why black holes unlock the quantum majesty of the Universe

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That scary swirling void from which nothing can escape is our perfect universal translation tool.

an astronaut contemplates a black hole

Key Takeaways

  • We can describe a vast array of natural phenomena, from photons to galaxies, using the language of mathematics.
  • The study of black holes has advanced quantum theory and the language of information and computing.
  • Information processing is a feature of our universe — and black holes are crucial to our cosmic understanding.

Excerpted from BLACK HOLES: The Key to Understanding the Universe by Brian Cox, Ph.D. and Jeff Forshaw, Ph.D. Copyright © 2023 by Brian Cox, Ph.D. and Jeff Forshaw, Ph.D. Reprinted by permission of Mariner Books, an imprint of HarperCollins Publishers.

Imagine you find a watch lying on the ground. On close inspection you are compelled to marvel at its delicate sophistication and exquisite precision. The mechanism was surely designed; there must have been a creator. Transpose ‘watch’ for ‘Nature’ and this is the argument for God presented by clergyman William Paley in 1802. We now understand that the argument is seriously undermined by the overwhelming evidence in support of Darwin’s theory of evolution by natural selection. The watchmaker is Nature, and it is blind. ‘There is grandeur in this view of life,’ wrote Darwin, ‘with its several powers, having been originally breathed into a few forms or into one; and that, while this planet has gone cycling on according to the fixed law of gravity, from so simple a beginning endless forms most beautiful and most wonderful have been, and are being, evolved.’ 

But what of the fixed law of gravity, a prerequisite for the existence of the planets on which the endless forms evolved? Or the laws of electricity and magnetism which glue the animals together? Or the menagerie of subatomic particles out of which we are made? Who or what laid down the laws; the framework within which everything cycles on? 

The story of modern physics has been one of reductionism. We do not need a vast encyclopedia to understand the inner workings of Nature. Rather, we can describe a near-limitless range of natural phenomena, from the interior of a proton to the creation of galaxies, with apparently unreasonable efficiency using the language of mathematics. In the words of theoretical physicist Eugene Wigner, ‘The miracle of the appropriateness of the language of mathematics for the formulation of the laws of physics is a wonderful gift which we neither understand nor deserve. We should be grateful for it.’

The mathematics of the twentieth century described a Universe populated by a limited number of different types of fundamental particles interacting with each other in an arena known as spacetime according to a collection of rules that can be written down on the back of an envelope. If the Universe was designed, it seemed, the designer was a mathematician. 

Today, the study of black holes appears to be edging us in a new direction, towards a language more often used by quantum computer scientists. The language of information. Space and time may be emergent entities that do not exist in the deepest description of Nature. Instead, they are synthesized out of entangled quantum bits of information in a way that resembles a cleverly constructed computer code. If the Universe is designed, it seems, the designer is a programmer. 

But we must take care. Like Paley before us, we are in danger of over-reaching. The role of information science in describing black holes may be pointing us towards a novel description of Nature, but this does not imply we were programmed. Rather we might conclude that the language of computing is well suited to describing the algorithmic unfolding of the cosmos. Put in these terms, there is no greater or lesser mystery here than Wigner’s miracle of the appropriateness of the language of mathematics for the formulation of the laws of physics. Information processing — the churning of bits from input to output — is not a construction of computer science, it is a feature of our Universe. Rather than spacetime-as-a-quantum-computer-code pointing to a programmer, we might instead take the view that earth-bound computer scientists have discovered tricks that Nature has already exploited. Viewed in this way, black holes are cosmic Rosetta Stones, allowing us to translate our observations into a new language that affords us a glimpse of the profoundest reason and most radiant beauty.

Black Holes May Be Engulfed In Dark Matter, Scientists Find

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By observing the orbits of stars in their pull, astronomers say they’ve found evidence that black holes are surrounded by substantial amounts of dark matter, according to a new study published in The Astrophysical Journal Letters.

Dark matter is tricky to study because you can’t observe it directly — even though it’s believed to make up some 27 percent of the universe, dwarfing the mere five percent of ordinary, or baryonic, matter that we can see.

We can, however, observe dark matter’s gravitational influence, which is where the stars come into play. The researchers looked at two nearby black holes, each forming a binary system where a companion star continues to orbit it. Normally, the orbits of these companion stars should gradually decay at an extremely minor rate of around 0.02 milliseconds per year.

In reality, what they observed blew that out of the water: an astonishingly higher rate of one millisecond per year — 50 times the theoretical estimation.

Gravitational Drag

Those findings, the researchers suspect, reeked of some dark matter meddling. So to corroborate the hunch, the researchers ran a computer simulation of a dark matter dynamical friction model, which helps calculate the loss of momentum of objects in space due to what is, in effect, “drag” caused by gravity.

They soon found that the simulated rate of orbital decay based on the dark gravity model lined up “precisely” with the rates of decay they observed in the companion stars, indicating that large amounts of dark matter, which would produce enough gravity to tamper with nearby orbits, are clumping around black holes.

“This is the first-ever study to apply the ‘dynamical friction model’ in an effort to validate and prove the existence of dark matter surrounding black holes,” Chan Man-ho, an astrophysicist at the Education University of Hong Kong, said in a statement. “The study provides an important new direction for future dark matter research.”

Easier Pickings

The team’s findings are some of the best evidence yet of a long-theorized “density spike” near black holes that should form from accreting dark matter.

Chan notes that previous studies relied on detecting gamma rays and gravitational waves, which are mostly produced by rare events like black hole mergers. Understandably, that doesn’t yield a lot of data for scientists to work with. Stars orbiting a black hole, on the other hand, are a little easier to come by.

“In the Milky Way Galaxy alone, there are at least 18 binary systems akin to our research subjects, which can provide rich information to help unravel the mystery of dark matter,” Chan said.

Light-bending gravity reveals one of the biggest black holes ever found

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An artist’s impression of a black hole, where the black hole’s intense gravitational field distorts the space around it. This warps images of background light, lined up almost directly behind it, into distinct circular rings. This gravitational “lensing” effect offers an observation method to infer the presence of black holes and measure their mass, based on how significant the light bending is. The Hubble Space Telescope targets distant galaxies whose light passes very close to the centers of intervening fore-ground galaxies, which are expected to host supermassive black-holes over a billion times the mass of the sun.

A team of astronomers has discovered one of the biggest black holes ever found, taking advantage of a phenomenon called gravitational lensing.

The team, led by Durham University, UK, used gravitational lensing—where a foreground galaxy bends the light from a more distant object and magnifies it—and supercomputer simulations on the DiRAC HPC facility, which enabled the team to closely examine how light is bent by a black hole inside a galaxy hundreds of millions of light years from Earth.

They found an ultramassive black hole, an object over 30 billion times the mass of our sun, in the foreground galaxy—a scale rarely seen by astronomers.

This is the first black hole found using the technique, whereby the team simulates light traveling through the universe hundreds of thousands of times. Each simulation includes a different mass black hole, changing light’s journey to Earth.

When the researchers included an ultramassive black hole in one of their simulations the path taken by the light from the faraway galaxy to reach Earth matched the path seen in real images captured by the Hubble Space Telescope.

The findings are published today in the journal Monthly Notices of the Royal Astronomical Society.

https://www.youtube.com/embed/thxU8PQUY7w?color=white A video showing how Astronomers used gravitational lensing to discover a black hole 30 billion times the mass of the sun in a galaxy 2 billion light years away. Credit: Durham University

Lead author Dr. James Nightingale, Department of Physics, Durham University, said, “This particular black hole, which is roughly 30 billion times the mass of our sun, is one of the biggest ever detected and on the upper limit of how large we believe black holes can theoretically become, so it is an extremely exciting discovery.”

A gravitational lens occurs when the gravitational field of a foreground galaxy appears to bend the light of a background galaxy, meaning that we observe it more than once.

Like a real lens, this also magnifies the background galaxy, allowing scientists to study it in enhanced detail.

Dr. Nightingale said, “Most of the biggest black holes that we know about are in an active state, where matter pulled in close to the black hole heats up and releases energy in the form of light, X-rays, and other radiation.”

“However, gravitational lensing makes it possible to study inactive black holes, something not currently possible in distant galaxies. This approach could let us detect many more black holes beyond our local universe and reveal how these exotic objects evolved further back in cosmic time.”

The study, which also includes Germany’s Max Planck Institute, opens up the tantalizing possibility that astronomers can discover far more inactive and ultramassive black holes than previously thought, and investigate how they grew so large.

The story of this particular discovery started back in 2004 when fellow Durham University astronomer, Professor Alastair Edge, noticed a giant arc of a gravitational lens when reviewing images of a galaxy survey.

Fast forward 19 years and with the help of some extremely high-resolution images from NASA’s Hubble telescope and the DiRAC COSMA8 supercomputer facilities at Durham University, Dr. Nightingale and his team were able to revisit this and explore it further.

The team hopes that this is the first step in enabling a deeper exploration of the mysteries of black holes, and that future large-scale telescopes will help astronomers study even more distant black holes to learn more about their size and scale.