Do black holes really exist?

Do black holes really exist?

Black holes from my knowledge are created from the collapse of a star's own gravity crushing itself, Now my question is well two questions, is it really infinitely dense to where space-time can be distorted to the point where it just stops? if so, this would mean objects caught in the event horizon would freeze and time would be stopped how is the black hole itself not effected by it's own mass wouldn't it just cease to exist in the first place?

The literal answer to your question is "yes". We can see clear astronomical evidence of black holes of a variety of sizes in this and other galaxies. It is possible of course that all that evidence is actually the result of some unknown physical process(es) and not black holes, but it would be a remarkable coincidence that it looks so much like we would expect black holes to look.

So I'll take your question as asking for a way to understand what black holes are. The best answer to that question is basically just equations -- solutions to the governing equations of general relativity that have event horizons, but I'm going to assume that is not what you want here.

So we are left looking for a better intuitive explanation or understanding, bearing in mind that this is at best inexact, and at worst misleading. If you have a lot of matter in a small region of space, and you look at it from the outside you see that the light coming from the surface of the region is red-shifted and (which is basically the same thing) that clocks on the surface seem to run more slowly. As you pack the matter in more tightly this effect becomes more pronounced. But because the clocks are running more slowly, whatever process is packing the matter in also runs more slowly. Eventually, as seen from the outside the clocks on the surface approach a complete standstill, and you will receive a final few extremely red-shifted photons from the surface and then nothing. What you have is now a black hole. From your point of view it is "frozen" and all you can see of it from the outside is the gravitational field surrounding it (and maybe an electric field as well). No information can ever leave it (I'm ignoring Hawking radiation and quantum mechanics in this answer, which is reasonable for big black holes).

Relativity being relativity, things can look quite different from another point of view. If you are falling freely into the black hole (and it is big enough that tides don't rip you apart) everything seems fine, as in this simulation Light from the rest of the universe is blue-shifted and increasingly distorted by gravity, but locally everything is OK. However, no matter what you do, within a finite time (a few days for the largest black holes we know about) you will reach a singularity -- a place where the equations of general relativity break down, and some other physics must presumably apply. We don't know what happens there, but we do know that no information about it can come back out of the black hole, so we can't send in any kind of probe to tell us about it.

The honest answer is: Nobody knows for certain.

They exist only in theories. Physicists regularly construct elaborate mathematical equations, and the Black Hole is something they essentially created to fill the gaps in certain theories, or to artificially 'complete' them.

In other words, for many of their theories to be correct, Black Holes MUST exist.

In reality, though, we have no idea. Something that's infinitely dense and small destroys all logic, physics and observable reality.

Do black holes really exist?

The conventional view of a black hole includes an “event horizon” beyond which nothing can escape. But a new calculation suggests collapsing matter may never get dense enough to form an event horizon, and “black stars” would form instead (Illustration: XMM-Newton/ESA/NASA)

Black holes might not exist – or at least not as scientists have imagined, cloaked by an impenetrable “event horizon”. A controversial new calculation could abolish the horizon, and so solve a troubling paradox in physics.

The event horizon is supposed to mark a boundary beyond which nothing can escape a black hole’s gravity. According to the general theory of relativity, even light is trapped inside the horizon, and no information about what fell into the hole can ever escape. Information seems to have fallen out of the universe.

That contradicts the equations of quantum mechanics, which always preserve information. How to resolve this conflict?


One possibility researchers have proposed in the past is that the information does leak back out again slowly. It may be encoded in a hypothetical flow of particles called Hawking radiation, which is thought to result from the black holes’ event horizons messing with the quantum froth that is ever-present in space.

But other researchers argue the information may never have been cut off in the first place. Tanmay Vachaspati and his colleagues at Case Western Reserve University in Cleveland, Ohio, US, have tried to calculate what happens as a black hole is forming. Using an unusual mathematical approach called the functional Schrodinger equation, they follow a sphere of stuff as it collapses inwards, and predict what a distant observer would see.

They find that the gravity of the collapsing mass starts to disrupt the quantum vacuum, generating what they call “pre-Hawking” radiation. Losing that radiation reduces the total mass-energy of the object – so that it never gets dense enough to form an event horizon and a true black hole. “There are no such things”, Vachaspati told New Scientist. “There are only stars going toward being a black hole but not getting there.”

Has anybody ever seen one?

That’s a slightly misleading question. Remember, the gravitational pull of a black hole is so strong that light cannot escape from it. And the only reason we can see things is light be emitted or reflected from them. So, if you ever saw a black hole, that’s exactly what it would look like: a black hole, a chunk of space devoid of light.

The nature of black holes means that they do not emit any signals – all electromagnetic radiation (light, radio waves etc.) travels at the same speed, c (approximately 300 million meters per second and the fastest speed possible) and is not fast enough to escape the black hole. Thus, we cannot ever directly observe a black hole from Earth. You can’t observe something that won’t give you any information, after all.

Luckily, science has moved on from the old idea of seeing being believing. We can’t directly observe subatomic particles, for example, but we know they’re there and what properties they have because we can observe their effects on their surroundings. The same concept can be applied to black holes. The laws of physics as they stand today will never allow us to observe anything beyond the event horizon without actually crossing it (which would be somewhat fatal).

The Ergosphere

A spinning black hole is more like a whirlpool than a pothole. The swirling water in this analogy is spacetime itself. It’s pulled around as the black hole rotates. This region of twisted spacetime is called the ergosphere. It is impossible to stand still in this region.

A spinning black hole has kinetic energy bound up in its spin, in the same way that a spinning top is more energetic than a top lying down. That energy can be tapped into and transferred to other things in the black hole’s environment. (The term ergosphere comes from the Greek word for “work.”) Astronomers think that a black hole powers its jets with energy from its spin.

New Class of Low-Mass Black Holes May Exist, Astronomers Say

In a paper published in the November 1, 2019 issue of the journal Science, a team of astronomers offers a new way to search for stellar-mass black holes, and shows that it is possible there is a class of black holes smaller than the smallest known black holes in the Universe.

An artist’s rendition of a giant star in orbit around a low-mass black hole. Image credit:

Stellar black holes often exist in something called a binary system. This simply means that two stars are close enough to one another to be locked together by gravity in a mutual orbit around one another.

When one of those stars dies, the other can remain, still orbiting the space where the dead star — now a black hole or neutron star — once lived, and where a black hole or neutron star has formed.

For years, stellar black holes astronomers knew about were all between 5 and 15 times the mass of the Sun. The known neutron stars are generally no bigger than about 2.1 solar masses — if they were above 2.5 solar masses, they would collapse to a black hole.

But in 2017, the LIGO Observatory detected two black holes merging together in a galaxy about 1.8 million light years away. One of those black holes was about 31 times the mass of the Sun the other about 25 times the mass of the Sun.

“Immediately, everyone was like ‘wow,’ because it was such a spectacular thing,” Ohio State University’s Professor Todd Thompson.

“Not only because it proved that LIGO worked, but because the masses were huge. Black holes that size are a big deal — we hadn’t seen them before.”

Professor Thompson and colleagues had long suspected that stellar black holes might come in sizes outside the known range, and LIGO’s discovery proved that they could be larger. But there remained a window of size between the biggest neutron stars and the smallest black holes.

The scientists decided to see if they could solve that mystery.

They used data from the Apache Point Observatory Galactic Evolution Experiment (APOGEE), which collected light spectra from around 100,000 stars across the Milky Way.

The spectra could show whether a star might be orbiting around another object: changes in spectra — a shift toward bluer wavelengths, for example, followed by a shift to redder wavelengths — could show that a star was orbiting an unseen companion.

The researchers narrowed the APOGEE data to 200 stars that might be most interesting.

They then analyzed images of each potential binary system from the All-Sky Automated Survey for Supernovae (ASAS-SN).

Their data crunching found a giant star called 2MASS J05215658+4359220 that appeared to be orbiting a massive unseen companion.

This binary system has an orbital period of 83 days and lies in the constellation Auriga, approximately 12,068 light-years from Earth.

The massive companion emits no light, including X-rays. This indicates the presence of a black hole that is not currently consuming any material.

“Constraints on the giant’s mass and radius imply that the unseen companion is 3.3 solar masses, indicating that it is a noninteracting low-mass black hole or an unexpectedly massive neutron star,” the astronomers said.

“What we’ve done here is come up with a new way to search for black holes, but we’ve also potentially identified one of the first of a new class of low-mass black holes that astronomers hadn’t previously known about,” Professor Thompson said.

“The masses of things tell us about their formation and evolution, and they tell us about their nature.”

Do black holes really exist? - Astronomy

Do black holes really exist or is it all just imagination? "Black Holes". that word is a mystery to all astronomers in the world. How do we know they exist? And if they do . how do we prove that they really do? Black holes form when a star that burns out of fuel starts to collapse on its own mass for a period of time. Once this process is over, the star has squeezed all its mass into one point. This one point is called a singularity. People might not believe it but at this point both time and space stop. Black holes have been known to pull stars and other heavenly bodies into its center by its gravity. There is a limit to where nothing can escape and where nothing can get away. This invisible circle around a black hole is called the event horizon. Anything that goes past the event horizon will no doubt get sucked into the black hole. Anything beyond the event horizon will not get sucked in, but will orbit the black hole. My project centered around black holes and whether they could exist. My research concluded that very large galaxies such as NGC 3379 must contain a black hole because the stars orbiting its center are moving faster than they should and they have shifted their spectral lines to the red. The only conclusion would be that a very massive object is causing this. The only known object in the universe that would cause this would be a black hole.

Do Black Holes Really Exist?

Frequently one sees science press headlines describing observations of black holes: the discovery of a black hole at the galactic center or the discovery of a pair of orbiting super massive black holes in merging galaxies or the aLIGO detection of gravitational waves created in the spin-down merger of a pair of binary black holes. These days, there are so many astrophysical observations on Earth and in space that are attributed to black holes that questioning their existence seems rather absurd.

However, it is important to point out that a black hole's event horizon, the region where time comes to a complete halt, has never been observed. Further, Hawking radiation, the predicted emission of thermal photons arising from quantum effects at the event horizon, has never been detected. The fact is that the term "black hole" is commonly used to indicate any collapsed stellar object that is more massive than a neutron star. Most of the "black hole" observations that we hear about come from emissions from the accretion discs of such massive compact objects, which may or may not actually be black holes.

What is the difference between black holes and other massive compact objects? Black holes are a major prediction of Einstein's general theory of relativity (GR), currently our standard model for gravity. GR predicts that when a massive fuel-exhausted star can no longer be prevented from final collapse by the repulsion of nuclear forces, its core falls inward in a supernova explosion and a black hole forms, complete with an event horizon at the Schwarzschild radius rg given by rg=2GM/c 2 , where G is Newton's gravitational constant, c is the speed of light and M is the mass of the star. Half a radius outside the event horizon, black holes have a region called the photosphere. In other words, the photosphere has a radius of 3/2 times rg. In the surface of the photosphere light is bent into a circular orbit by gravity and can orbit the compact object.

The presence of an event horizon is the essential defining characteristic of a black hole. It is the surface within which gravity is so large that the time-slowing effect of the gravitational red shift causes time to stop altogether. To an external observer, any infalling object would appear to stop and freeze on the event horizon and would never go any farther in. On the other hand, according to GR an unfortunate observer who was falling into the black hole would notice no particular effect when crossing the event horizon.

The interior of a black hole inside the event horizon is causally disconnected from the outside, and nothing that enters the event horizon can escape (except for advanced waves see my book The Quantum Handshake, Sec. 6.21). Like Las Vegas, whatever happens inside the event horizon stays inside the event horizon. Furthermore, GR predicts the eventual formation of a pathological singularity within the event horizon. The singularity is completely isolated from the outside world, shielded from it by the event horizon. However, within the singularity's domain of influence the familiar laws of physics must break down, with unknown consequences.

There are a number of reasons why many physicists distrust the above GR description of black hole formation and behavior. The singularity, whether hidden or not, is considered by some to be an unphysical deal-breaker as a prediction of a physics theory. Further, the GR description ignores the effects of quantum mechanics. There is an intrinsic incompatibility between our present standard theories of general relativity and quantum mechanics, and we do not have a theory that correctly includes the effects of both. It is speculated the if we did have a more comprehensive theory of quantum gravity, it would significantly alter the scenario of black hole formation, particularly in the regions of the event horizon and the singularity.

One critic of GR is George Chapline of the Lawrence Livermore National Laboratory (see AV 129 in the September-2005 issue of Analog). Chapline has argued that, if properly applied, quantum mechanics will not permit gravitational time dilation to stop time altogether. He cites a similar situation that occurs within a cylinder of super-fluid helium, in which at a certain vertical location the speed of sound attempts to go to zero. He points out that a phase transition in super-fluid helium prevents this from happening, and he argues that a similar phase transition must occur in a collapsing star, which will prevent the formation of an event horizon. Protons and neutrons must transition to leptons and mesons, which must in turn transition to dark energy, and the repulsion generated by the dark energy halts the collapse before an event horizon can form. Chapline's work is but one example of the many GR critics who have proposed alternatives or modifications of GR that would qualitatively change the stellar collapse scenario and would prevent the formation of black holes with event horizons. This raises the question of whether these ideas and theories, questioning the very existence of black holes, can be tested by observation.

Recently, V. Cardoso and P. Pani of the University of Lisbon have proposed such an observational test. They first survey the various non-GR models of star collapse and divide the resulting collapsed stars into: (1) exotic compact objects (ECOs) with radii smaller than a neutron star but larger than the photosphere, (2) ultra-compact objects (UCOs) with radii near the photosphere radius, and (3) clean photosphere objects (ClePhOs) with radii only about 1.65% larger that the event horizon radius rg. All of these objects would have an accretion disc and, based strictly on observation of their emissions of light and radio waves, would be indistinguishable from a black hole. However, they are predicted to show distinguishable differences when gravitational waves are generated by a merger.

The aLIGO Detector, with sites in Hanford, Washington and Livingston, Louisiana, has now detected gravitational waves three times: on September 14, 2015, on December 26, 2015, and on January 4, 2017, with a fourth lower confidence event also detected on October 12, 2015. The analysis of these events indicates that all were produced by mergers of pairs of massive compact objects with masses ranging between 6 and 37 times the mass of our Sun.

The gravitational wave signature of such mergers is a "ringdown", a set of wiggles in the signal that rise in frequency during the transition from two massive compact objects to a single one. The ringdown is predicted to be slightly different for ECOs and UCOs than for black holes, and more precise observations of gravitational waves from mergers could reveal these differences. For ClePhOs Cardoso and Pani predict that the ringdown itself is the same as for black holes, but that a fraction of the gravity waves generated should be briefly trapped between the object's surface and its photosphere. In this case, the characteristic ringdown signal would be followed by a sequence of "echo" wiggles that would persist for a few hundred milliseconds after the primary signal. The magnitude of these echoes and how fast they die out would depend on the details of the ClePhO formation, permitting some discrimination between different models.

One group of physicists from Waterloo, Canada and Tehran, Iran has analyzed the three aLIGO events that were detected in 2015 in search of echo signals. Interestingly, they obtained a positive indication of the presence of echoes. However, because of the noise present in the data their result had a statistical significance of less than three standard deviations. A result must have six or more standard deviations to be considered a definite observation. Thus, it is inconclusive but tantalizing. Improved analysis of this type will probably have to wait for more events and for more new gravitational wave detectors to come online.

If such echo signals were actually observed with convincing statistical significance, the observation would have major consequences for gravitational physics. It would be interpreted as falsifying GR and supporting rival non-GR theories that predict compact objects with no event horizon. However, while the detection of gravitational waves by aLIGO has been a major triumph, the aLIGO system has been fighting noise since its original construction, and the present noise level only makes possible the unambiguous detection of the ringdown signal. The two aLIGO stations currently in operation are simply too noisy to observe the predicted ringdown differences or echoes.

However, this may change soon. The Virgo gravitational wave detector in Pisa, Italy is scheduled to join the aLIGO configuration next year, and there are also gravitational wave detector stations under development or construction in India, Germany, and Japan. Reduced noise from design improvements and signal averaging among more detector stations observing the same gravitational wave event may reduce the noise level significantly. The addition of more interconnected detectors positioned around the planet will also greatly improve that sensitivity of the system to the polarization of the gravitational waves. This is a crucial observable in distinguishing between GR and many of its alternatives.

On a longer timescale, the 2017 LISA space-based gravitational wave detector, re-planned several times, is now scheduled to be launched in the 2030s. This project of the European Space Agency is a gravitational wave detector in the form of an equilateral triangle 2.5 million kilometers on a side with a laser interferometer unit at each vertex. The 2017 LISA gravitational wave detector is presently planned to orbit the Sun at the Lagrange L3 point on the side of the Sun away from Earth, but in the same orbit as the Earth.

Earth-based gravitational wave detectors like aLIGO have sensitivity in the frequency range from 1 Hz to 30 kHz, which is the region where signals from massive black hole mergers are strongest. The 2017 LISA gravitational wave detector will have sensitivity in the 10 -5 Hz to 1 Hz region, where many binary star systems have their peak emission of gravitational waves. For technical reasons 2017 LISA cannot use the high-finesse Fabry-Pérot resonant-arm cavities and signal recycling systems used by aLIGO. For this reason, its absolute sensitivity to changes in arm length will be an order of magnitude poorer than aLIGO. However, since its arm lengths are a million times greater, this should not be a problem, and excellent low noise detections are expected from the 2017 LISA system.

In any case, in 2015 the aLIGO detection of gravitational waves opened a new window on the universe. The developing detector technology promises to make it possible to answer the question of whether the black holes, as predicted by Einstein's general theory of relativity, actually exist, or whether quantum effects and other considerations rule out black holes and indicate that collapsed stars have a different form. As more and better detectors come online, we can expect an answer to this important question.

John G. Cramer's 2016 nonfiction book (Amazon gives it 5 stars) describing his transactional interpretation of quantum mechanics, The Quantum Handshake - Entanglement, Nonlocality, and Transactions, (Springer, January-2016) is available online as a hardcover or eBook at: or

SF Novels by John Cramer: Printed editions of John's hard SF novels Twistor and Einstein's Bridge are available from Amazon at and His new novel, Fermi's Question may be coming soon.

Alternate View Columns Online: Electronic reprints of 212 or more "The Alternate View" columns by John G. Cramer published in Analog between 1984 and the present are currently available online at: .

Black Hole Existence Tests:

"Tests for the existence of horizons through gravitational wave echoes", Vitor Cardoso and Paolo Pani, Nature Astronomy 1, 586-591 (2017)

"Echoes from the Abyss: Evidence for Planck-scale structure at black hole horizons", J. Abedi, H. Dykaar, and N Afshordi, (December-2016) arXiv:1612.00266 [gr-qc] and

"Echoes from the Abyss: The Holiday Edition!", J. Abedi, H. Dykaar, and N Afshordi, (January-2017) arXiv:1701.03485 [gr-qc].

News: Do black holes really exist?

But you know this. Infinitely small, with huge gravity, warpers of time and space they’re simply cool to astronomer and the public alike.

Everything about them is interesting. They form when massive stars explode in titanic supernovae, they sit in the centers of big galaxies (like ours!) with masses millions or billions of times that of the Sun, and if they’re feeding on material around them they can form disks of swirling material which can easily outshine the rest of the galaxy combined.

No astronomer doubts that these gravitational objects actually exist. But astronomers Tanmay Vachaspati, Dejan Stojkovic, and Lawrence Krauss at Case Western Reserve University have written a new paper which has thrown a monkey in the wrench about the exact, well, “surface” of a black hole. Here’s how this works.

When a massive star ends its life, the core collapses. As the core shrinks, its surface gravity increases (that is, the gravity you would feel if you were standing on its surface). This means the escape velocity increases as well – this is how fast an object would have to move to be able to break free and escape to infinity. For the Earth it’s about 11 km/sec (7 miles/sec), and for the Sun it’s about 600 km/sec (400 miles/sec). The escape velocity of a body depends on how massive it is and how big it is. For a given mass, a smaller body has a higher escape velocity.

So as the core of the star shrinks, the escape velocity increases. At some point, if the core has enough mass, the escape velocity reaches the speed of light. This means that if you are standing there on the core’s surface, you would need to move at the speed of light to escape (actually, the situation is more complicated than this, but I’m simplifying). It’s like an infinitely deep hole any matter in it cannot get out.

If the core shrinks just a wee bit more, not even light can escape. To an outside observer, the core becomes black. So let’s see, it’s a hole, and it’s black. What should we call such a thing?

Anyway, the theory is that the mass inside the black hole shrinks all the way to a point, an object of infinitely small size, called a singularity. The region around it where the escape velocity equals the speed of light is called the event horizon. And this is where things get sticky.

Einstein showed that as gravity increases, your clock runs slower. Literally, if you have two people, one guy up high above a black hole, and another guy close in, the guy outside sees the close-in guy’s clock running slower. Literally, time flows more slowly near an object with gravity, and the stronger the gravity the slower time flows relative to an outside observer. For a black hole, time literally stretches to infinity at the event horizon. Clocks stop. Update: Well, I was being glib. Actually they continue to slow, ever approaching stopping but never actually reaching it. I was trying to simplify, but oversimplified – I make similar comments below in this entry, so where you read that things stop, think of it as “slowing almost to but never quite reaching zero”. Read the comments thread below for details.

This brings up a very interesting situation. If time takes forever to flow, then how does a black hole ever form? Imagine the core collapsing, and you’re looking at it from far away. You see it getting smaller, but the collapse also appears to be going more slowly because of the time dilation. Like Zeno’s paradox, you see the escape velocity approach the speed of light, but you’ll never see it actually get to the speed of light! Time would stretch out infinitely, and the collapse of the core would appear to you to stop.

But it gets worse. Years ago, Stephen Hawking discovered that black holes can in fact “leak” out mass. It’s very complicated, and has to do with entropy and quantum mechanics, so forgive me if I leave out details. Let’s just say that black holes can evaporate, and go from there.

From the black hole’s viewpoint, time flows just fine. It starts to form, and it starts to very slowly lose mass through Hawking radiation. Over time, billions of years or more, it eventually evaporates away.

But from your point of view, high above the black hole, the event horizon never quite actually forms. It gets closer and closer, remember, but slower and slower. Yet the Hawking radiation isn’t really affected by this. So the two effects compete: the event horizon never totally forms because it would take an infinite amount of time, but during that time the hole is losing mass. So the black hole will actually evaporate before it ever really becomes a black hole.

If you throw something, let’s say a wad of paper, into the black hole, you would actually see the black hole evaporate (if you could wait long enough) before you’d see the paper wad get to the event horizon. So the black holes loses mass faster than it can gain mass and the event horizon can never actually form.

This idea makes scientists nuts. And this is what the new paper is about. Some people have thought that if you take quantum mechanics into account, this paradox may be resolved. What the authors appear to have shown is that QM doesn’t help. The black hole itself, the event horizon, never really forms.

However, have a care here: there is still a massive, dense, highly gravitational object there! So we still have what are essentially black holes in the cores of galaxies and forming when stars explode and all that, it’s just that, technically, well, they aren’t actually black holes.

I will note that this is how I understand the situation, and I may have it wrong. This is very complicated stuff! This paper is by no means the last word on the subject – even the experts argue incessantly about it, and I’m no expert. This is a very interesting situation, and I’m quite sure that it is nowhere near being resolved. I have many friends who study black holes and I’m sure they’ll have quite the reaction to this story. If I hear more I’ll post again. I guarantee that this idea won’t, ah, evaporate on its own anytime soon.

The Discovery of Stellar-Mass Black Holes

Because X-rays are such important tracers of black holes that are having some of their stellar companions for lunch, the search for black holes had to await the launch of sophisticated X-ray telescopes into space. These instruments must have the resolution to locate the X-ray sources accurately and thereby enable us to match them to the positions of binary star systems.

The first black hole binary system to be discovered is called Cygnus X-1. The visible star in this binary system is spectral type O. Measurements of the Doppler shifts of the O star’s spectral lines show that it has an unseen companion. The X-rays flickering from it strongly indicate that the companion is a small collapsed object. The mass of the invisible collapsed companion is about 15 times that of the Sun. The companion is therefore too massive to be either a white dwarf or a neutron star.

A number of other binary systems also meet all the conditions for containing a black hole. Table 1 lists the characteristics of some of the best examples.

Black hole news: 'Stupendously large black holes' could exist

Link copied

Black hole: Experts discuss &lsquooutlandish&rsquo theories

When you subscribe we will use the information you provide to send you these newsletters. Sometimes they'll include recommendations for other related newsletters or services we offer. Our Privacy Notice explains more about how we use your data, and your rights. You can unsubscribe at any time.

Astronomers already know of the existence of supermassive black holes (SMBHs), which can reach up to 10 billion masses of the Sun. However, new research has hinted that black holes could grow even bigger, with space experts giving them the tag stupendously large black holes or SLABS.


SMBHs form in the centre of a galaxy and grow to their enormous sizes by consuming stars and all other matter which crosses their paths.

This would mean there is an upper limit to the size they can reach as there is only so much around them which can be consumed.

SLABS, on the other hand, could have formed shortly after the Universe came into existence through the Big Bang.

Black holes which formed in the early Universe are known as primordial black holes.

Black hole news: 'Stupendously large black holes' could exist (Image: GETTY)

Known black holes can reach up to 10 billion masses of the Sun (Image: GETTY)

Professor Bernard Carr said: &ldquoWe already know that black holes exist over a vast range of masses, with a SMBH of four million solar masses residing at the centre of our own galaxy.

"Whilst there isn&rsquot currently evidence for the existence of SLABs, it&rsquos conceivable that they could exist and they might also reside outside galaxies in intergalactic space, with interesting observational consequences.

"However, surprisingly, the idea of SLABs has largely been neglected until now.

&ldquoWe&rsquove proposed options for how these SLABs might form, and hope that our work will begin to motivate discussions amongst the community.&rdquo

Black holes are terrifying entities (Image: GETTY)

Related articles

Primordial black holes did not form from collapsing stars, and there is not really a definitive theory on how they came to be.

One suggestion is that in the first moments of the Universe, fluctuations in mysterious dark matter could have resulted in some regions collapsing into black holes.

As a result, there is no upper limit to their size, and researchers from the Queen Mary University of London believe they could grow even more unfathomably large.

The research could also help experts understand more about dark matter.

What is a black hole? (Image: EXPRESS)

Related articles

Despite not knowing what exactly dark matter is, experts do know that it is essential to the Universe.

The likes of NASA believe dark matter is an invisible force which holds galaxies and clusters together, and has been key in the formation of the Universe.

The substance also adds mass to the galaxies, but a mass which cannot be seen or detected with scientific instruments.

Prof Carr added: &ldquoSLABs themselves could not provide the dark matter.

"But if they exist at all, it would have important implications for the early Universe and would make it plausible that lighter primordial black holes might do so.&ldquo