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

Space background showing a black hole and galaxy.
(Image credit: Shutterstock)

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.

Related: 9 ideas about black holes that will blow your mind

Welcome to a holographic superconductor

There are all sorts of potential, hypothetical black holes: ones with or without electric charge, ones spinning or stationary, ones surrounded by matter or those floating in empty space. Some of these hypothetical black holes are known for certain to exist in our universe; for example, the rotating black hole surrounded by infalling matter is a pretty common presence. We've even taken a picture of one.

But some other kinds of black holes are purely theoretical. Even so, physicists are still interested in exploring them — by diving into their mathematical foundations, we can realize new relationships and implications of our physical theories, which can have real-world consequences. 

One such theoretical black hole is an electrically charged black hole surrounded by a certain kind of space known as anti-de Sitter. Without getting into too much of the nitty-gritty, this kind of space has constant negative geometric curvature, like a horse saddle, which we know is not a good description of our universe. (A cosmos with anti-de Sitter space, all else being the same, would have a negative cosmological constant, which means that any matter would tend to condense into a black hole, versus the known accelerating expansion that is flinging the universe apart. 

This horse-saddle space doesn't exist in our universe, But that's okay: It turns out that these exotic black holes still have surprisingly intricate structures worth exploring.

Related: The 18 biggest unsolved mysteries in physics

One of the reasons it's worth exploring is that charged black holes share a lot of similarities with rotating black holes, which certainly do exist in our universe, but charged black holes are mathematically simpler to grapple with. So by studying charged black holes we can gain some insights into real-world rotating black holes. 

Also, physicists have found that when these black holes become relatively cool, they build up a "haze" of quantum fields around their surfaces. This haze sticks to the surface, pulled inward by the never-tiring gravity of the black hole itself, but pushed outward by the electric repulsion of the same black hole. A haze of quantum fields operating in stability on a surface is also known as a superconductor. Superconductors have real-world applications (namely, they can transmit electric current with no resistance), so seeing how superconductors play out in these exotic scenarios helps us understand their mathematical structures, which can potentially lead to new insights with actual applications. 

In a study published Aug. 28 to the preprint database arXiv, a team of researchers has recently used the language of superconductivity to discover what lies farther beneath the surface of these hypothetical black holes.

Let's dive in.

The almost-wormhole

"Normal" charged black holes — those surrounded by a typical garden-variety space-time that you might find in our universe — have a few quirks on their inside. First, beyond the event horizon (the boundary of every black hole, where once you fall in you can't get out) lies something called an inner horizon, a region of intense quantum energies. Beyond that is a wormhole, a bridge to a white hole in some other lonely section of the universe (at least, according mathematics). 

Related: Where do black holes lead?

I should note here that we don't really know whether wormholes like this exist in real life, because the mathematics of charged black holes breaks down at the inner horizon, and nothing more can be learned until we develop new physics. Fortunately, the charged black holes surrounded by anti-de Sitter space, which for now we'll call superconductor black holes, avoid this problem.

The good news is that the inner horizon of a superconductor black hole breaks down, allowing you to smoothly sail past it without getting spaghettified as you would in an ordinary, stationary black hole. The bad news is that the wormhole bridge inside a superconductor black hole also tears itself apart, so you don't get to transport yourself to the distant stars.

But that doesn't mean that nothing interesting happens to you. Just inside what would have been the inner horizon, the interior of a superconductor black hole gets a little frothy.

Normally, particles in a real-life superconductors can oscillate, supporting waves sloshing back and forth in an effect known as Josephson Oscillations. And deep inside these black holes, space itself vibrates back and forth. If you were to physically fall into one of these beasts, you'd be in for a bumpy ride.

A strange universe

But once you made it past the vibrating space-time, what comes next is truly mystifying. The researchers discovered that the innermost regions of a superconductor black hole can feature an expanding universe in grotesque miniature, a place where space can stretch and deform at different rates in different directions.

Related: 5 reasons we may live in a multiverse

What's more, depending on the temperature of the black hole, some of these regions of space can trigger a new round of vibrations, which then create a new patch of expanding space, which trigger a new round of vibrations, which then create a new patch of expanding space, and so on and so on at ever smaller scales.

It would be a mini fractal universe, repeating endlessly from large scales to small. It's downright impossible to describe what it would be like to traverse such a landscape, but it would surely be weird.

At the center of this strange fractal, chaotic mess is the singularity: the point of infinite density, the place where every bit of matter that ever fell into the black hole resides.

Unfortunately, even with their super-charged superconducting mathematical techniques, the researchers can't describe what happens at the singularity. All known physics breaks down, requiring new theories of gravity to fully describe. 

Who knows what you'll find at the center of a superconductor black hole, but at least you'll enjoy the ride down.

Originally published on Live Science.

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Paul Sutter
Space.com Contributor

Paul M. Sutter is an astrophysicist at SUNY Stony Brook and the Flatiron Institute in New York City. Paul received his PhD in Physics from the University of Illinois at Urbana-Champaign in 2011, and spent three years at the Paris Institute of Astrophysics, followed by a research fellowship in Trieste, Italy, His research focuses on many diverse topics, from the emptiest regions of the universe to the earliest moments of the Big Bang to the hunt for the first stars. As an "Agent to the Stars," Paul has passionately engaged the public in science outreach for several years. He is the host of the popular "Ask a Spaceman!" podcast, author of "Your Place in the Universe" and "How to Die in Space" and he frequently appears on TV — including on The Weather Channel, for which he serves as Official Space Specialist.

  • David-J-Franks
    Admin said:
    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: charged black holes.

    A mini fractal universe may lie inside charged black holes (if they exist) : Read more
    From article;

    "At the center of this strange fractal, chaotic mess is the singularity: the point of infinite density, the place where every bit of matter that ever fell into the black hole resides."

    Paul Sutter, what is a point of infinite density?
    Reply
  • kristianna276
    In a hypothetical universe a trillion angles can dance on the head of a pin, in reality nobody has ever seen a tiny dancing angel. In the strange fractal universes where universe hide in plan sight within the stranger than strange black holes. This unproven model of factual models that places universes inside this universe, making an infinite array of universes. Since we accept the notion that nada exists outside our universe, we must look inward in order to discover the endless possibilities of limitless universes. Many have claimed that we are the only show in town, and that time has a beginning and time will have an end. Amen. Time, space and matter all began some 14 billion years ago. So nada existed before the BB (Big Bang). Maybe we should be looking for the smoking BB gun. Factually speaking, we want to prove that there are infinite number of us, we have to use self introspection in order to find the answer to source of our self awareness. The infinite universes that lie outside of ourselves that makes us aware of ourselves. A Blacker than Black, Black Hole would provide us with the insight to seeing the infinite through the gravitational lensing to see the finite. In theory a stranger than strange Black Hole could be the gateway to infinite universes. Like Alice through the Looking Glass, we tumble down the Rabbit hole of the infinite to emerge sound into a yet undiscovered universe. The possibilities are endless. Will we ever discover these Black Holes? Will we one day traverse the endless bounty of infinite realms of existence? Be damned if I know. It is all theory and no real logic.
    Reply
  • Atlan0001
    David-J-Franks said:
    From article;

    "At the center of this strange fractal, chaotic mess is the singularity: the point of infinite density, the place where every bit of matter that ever fell into the black hole resides."

    Paul Sutter, what is a point of infinite density?
    Unmeasurable.

    A density of mass far beyond any measure, in a point (and/or Point of points ( Infinitesimal of an infinity of infinitesimals)). The Big Crunch. And, at one the same time, the biggest, most continuous, Hole (of holes (Space of spaces)) you could ever imagine. The biggest, most continuous, Well of wells (Vortex of vortices) (Vacuum of vacuums) you could ever imagine. irresistible force of immovable object (The(!) Singularity of singularities).

    Maybe even the reverse of the coin of 'Renormalization'; to infinity rather than finite.

    And I wonder if I put enough superlative redundancies up there?
    Reply
  • kristianna276
    Can a point that is unmeasurable ever exist? The existence of this "strange" fractal is all speculative and does not exist in reality. We are just exploring the physics of Black Holes, and many of our cherished believes may have to be scraped to the science of reality. Believing in these Fractal Universes is like believing that the world is flat, and we are the center of the universe. If these universes do exist then they are gateways to universes outside our own. Space and time are limitless and the number of universes, outside our own, is limitless. Maybe wormholes exits through these Black Holes, but Fractal Universes don't exist.
    Reply
  • Atlan0001
    kristianna276 said:
    Can a point that is unmeasurable ever exist? The existence of this "strange" fractal is all speculative and does not exist in reality. We are just exploring the physics of Black Holes, and many of our cherished believes may have to be scraped to the science of reality. Believing in these Fractal Universes is like believing that the world is flat, and we are the center of the universe. If these universes do exist then they are gateways to universes outside our own. Space and time are limitless and the number of universes, outside our own, is limitless. Maybe wormholes exits through these Black Holes, but Fractal Universes don't exist.
    Every point of it is the exact center of an infinite Universe. There is no direction left or right of center, up or down from center, center point is every point everywhere whatsoever in such an infinite. Some of what you say is not bad, Not bad at all. But "fractal....does not exist in reality." "....., But Fractal Universes don't exist." There you imploded. Like the rest of us who make claims on cosmology and have to face naysayers, prove it! Prove fractal universes don't exist.

    An infinite Universe will include an infinity of differences, different universes, within the boundarylessness going away from every point. But, eventually, what goes away in the infinity of universes, as to differences, will begin to develop, come to, a difference that is the exact twin of the original point universe. Not exactly the same universe, not at all the same universe, but being an exact twin down to the very last particle, and everything else, of it.

    Even being an infinite distance apart, all of an infinity of such twins spread infinitely far apart across an infinity, being exact twins down to the last particle, I long ago began to wonder if there was the possibility of entanglement. If there is the possibility of "spooky action" at an distance. That would mean boundaries also entangling with boundaries...and on and on and on. At that point, in that realization of potential entanglement, you are now dealing in a hyper-finite rather than complete infinity. Or, rather, a hyper-finite along with, mixed with, infinity. Laid onto infinity (essentially singularly planed). The infinity still remains, fully remains, yet it also transforms, reduces, even rises, to fractalization (one fractal, mirrored to infinity in self-similarity). Chaos Theory's grain, smooth, grain, smooth.... (finite, infinite, finite, infinite...), vertical layering to infinity (ultimately to end in; is it grainy finite? Is it smooth infinity?).
    Reply