Physicists have discovered an odd twist of space-time that may mimic black holes — until you get too close. Generally known as “topological solitons,” these theoretical kinks in the material of space-time could lurk throughout the universe – and finding them could push forward our understanding of quantum physics, in line with a brand new study published April 25 within the journal Physical Review D.
Black holes are perhaps essentially the most frustrating object ever discovered in science. Einstein’s general theory of relativity predicts their existence, and astronomers understand how they form: All it takes is for a large star to collapse under its own weight. With no other force available to withstand it, gravity just keeps pulling in until all of the star’s material is compressed into an infinitely tiny point, referred to as a singularity. Surrounding that singularity is an event horizon, an invisible boundary that marks the sting of the black hole. Whatever crosses the event horizon can never get out.
However the principal problem with that is that points of infinite density cannot really exist. So while general relativity predicts the existence of black holes, and we’ve got found many astronomical objects that behave exactly as Einstein’s theory predicts, we all know that we still haven’t got the complete picture. We all know that the singularity should be replaced by something more reasonable, but we do not know what that something is.
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Figuring that out requires an understanding of extremely strong gravity at extremely small scales — something called quantum gravity. So far, we’ve got no viable quantum theory of gravity, but we do have several candidates. One in all those candidates is string theory, a model that implies all of the particles that make up our universe are really fabricated from tiny, vibrating strings.
To clarify the wide range of particles inhabiting our universe, those strings cannot just vibrate in the standard three spatial dimensions. String theory predicts the existence of additional dimensions, all curled up on themselves at some unfathomably small scale — so small that we won’t tell those dimensions are there.
And that act of curling up extra spatial dimensions at incredibly tiny scales can result in very interesting objects.
In the brand new study, researchers proposed that these compact extra dimensions can provide rise to defects. Like a wrinkle that you just just cannot get out of your shirt irrespective of how much you iron it, these defects can be stable, everlasting imperfections within the structure of space-time — a topological soliton. The physicists suggested that these solitons would largely look, act and possibly smell like black holes.
The researchers studied how rays of sunshine would behave when passing near one in every of these solitons. They found that the solitons would affect the sunshine in almost the identical way as a black hole would. Light would bend across the solitons and form stable orbital rings, and the solitons would forged shadows. In other words, the famous images from the Event Horizon Telescope, which zoomed in on the black hole M87* in 2019, would look almost the exact same if it were solitons in the middle of the image, somewhat than a black hole.
But up close the mimicry would end. Topological solitons will not be singularities, so that they do not need event horizons. You could possibly get as close as you desired to a soliton, and you could possibly all the time leave when you desired to (assuming you packed enough fuel).
Unfortunately we’ve got no black holes close enough to dig around in, and so we are able to only depend on observations of distant objects. If any topological solitons are ever discovered, the revelation would not just be a significant insight into the character of gravity, however it would enable us to directly study the character of quantum gravity and string theory as well.