To earthlings looking into space, our solar system appears to be surrounded by billions of stars in the Milky Way. But if we looked further, would it be possible to find evidence that we were in something more amazing, like a black hole?
Black holes are places in the universe where gravity is so strong that it warps time and space around them; Once inside, nothing—not even light—can get out.
In one scenario, the Earth could have been swallowed up by a black hole long ago. But if this happened, the gravity would be catastrophic Gaurav Khanna, a black hole physicist at the University of Rhode Island. As Earth approaches the black hole, time slows down. And depending on the size of the black hole, matter in it can expand Spaghetti-like shapes. Khanna told Live Science that even if the planet survived this “spaghettitation,” the Earth would be bound by a dense, small singularity, where it would be incinerated by the pressure and temperature of an unfathomable gravitational force.
We can therefore rule out the possibility that a black hole may have swallowed the Earth at some point in its history; Khanna said it would have been erased in a split second.
Related: How is a black hole formed?
But there’s another way Earth might have ended up in the belly of a black hole: it might have formed there.
“A black hole looks a lot like the Big Bang in reverse,” Khanna said. “The math looks the same.” As a black hole collapses onto a tiny point of extreme density, the Big Bang exploded from this point.
One theory posits that the Big Bang was the beginning of a black hole singularity in a larger universe. Khanna said the dense center is compressed and compressed “until it somehow explodes and a mini universe forms inside the black hole.”
This theory, known as Schwarzschild cosmology, suggests that our universe now expanding inside a black hole is part of an original universe. Theoretically, this scenario could mean that universes can exist within universes, like Russian nesting dolls, and that returning through a black hole — a feat likely impossible, since light can’t even make a reverse trip — would open up worlds unknown, Khanna said. .
However, this theory is unlikely to ever be proven; Nothing can travel through a Black hole event horizon.
But if Earth is inside a black hole, experts have some estimates of the size of the chasm of space. He said: “If we are in a black hole, then it must be very massive.” Scott FieldAssociate Professor of Mathematics at the University of Massachusetts Dartmouth. Not only is the Earth immersed in a black hole the size of a planet or even a hole the size of the solar system. If that were the case, Field told Live Science, scientists would have taken note. There would be observable fingerprints of the black hole’s spin. Or we might see subtle distortions caused by intense gravity – such as the slowing of time and the expansion of matter – as people move inside the black hole.
If Earth were contained in an Earth-size black hole, for example, people would notice the effects of tidal forces, such as macaroni veins and slow time, as they moved from one spot on the globe to another, said Field, who works on gravity modeling and simulations, Including the collision of the black hole.
Any black hole called Earth would have to be supermassive, Field said, about the size of the universe and too vast for us to travel far enough or fast enough to detect gravitational distortions.
From inside a black hole universe, Khanna said, “Earthlings would have no way of knowing that there was another original universe in existence.” We will be oblivious to that. So finding our global ancestor would be difficult, to say the least. However, he said, “It would be cool” if this theory were true.