# Physicists Have Figured Out How To Make It Through A Wormhole

For years, physicists have used Einstein's theory of general relativity to assume that the center of a black hole contains a singularity - the point at which time and space effectively end. When an object approaches the event horizon, the point where the gravitational pull becomes too great for anything to escape, it would be crushed in one direction and stretched in the other. If the object stays in the black hole long enough to make it to the center, it would essentially be cosmic spaghetti.

But earlier this year, physicists from the University of Cambridge argued that there's no reason why a singularity necessarily has to be on the inside of a black hole. Instead, they suggested that in a universe with five or more dimensions, there is the possibility of a singularity not bound by an event horizon, dubbed a "naked singularity."

This theory would rattle our current understanding of how the laws of physics govern our universe, because it basically presupposes that Einstein's theory of relativity is wrong.

So, assuming that the stipulations of general relativity are flexible, the new study from the University of Lisbon, led by Diego Rubiera-Garcia, argues that if you replace the singularity in the center of a black hole with a naked singularity, you get a finite-sized wormhole. They then took this one step further, and calculated what would happen if various objects, known as observers, made it into the wormhole.

Rubiera-Garcia and his team modeled these observers as a group of points connected by physical or chemical interactions that holds everything together as it moves. As Rubiera-Garcia explains, "Each particle of the observer follows a geodesic line determined by the gravitational field. Each geodesic feels a slightly different gravitational force, but the interactions among the constituents of the body could nonetheless sustain the body." To clarify, a geodesic line is simply a path in spacetime that a free-falling object follows.

What Rubiera-Garcia and his team demonstrated was that finite forces, no matter how strong, could compensate for the impact of the gravitational field near and inside the wormhole on a physical body travelling through it. This means that while under the theory of general relativity, an object approaching a black hole will be spaghettified, under the "naked horizon" theory, the object can only be crushed just as much as the size of the wormhole.

In a broader sense, this means that an observer could survive a journey through the wormhole and make it to the other side -potentially to another universe- though it would be crushed to the size of a finite wormhole. "For a theoretical physicist, the suffering of observers is admissible (one might even consider it part of an experimentalist's job) but their total destruction is not," said Rubiera-Garcia.

Until we are able to actually interact with black holes in more ways, all of this work remains purely hypothetical. But, along with new technology to help us take the first ever real picture of a black hole, we are slowly uncovering more and more mysteries, truths, and theories about these terrifying space phenomenon.

But earlier this year, physicists from the University of Cambridge argued that there's no reason why a singularity necessarily has to be on the inside of a black hole. Instead, they suggested that in a universe with five or more dimensions, there is the possibility of a singularity not bound by an event horizon, dubbed a "naked singularity."

This theory would rattle our current understanding of how the laws of physics govern our universe, because it basically presupposes that Einstein's theory of relativity is wrong.

"If naked singularity exists, general relativity breaks down. And if general relativity breaks down, it would throw everything upside down, because it would no longer have any predictive power - it could no longer be considered as a standalone theory to explain the universe," Saran Tunyasuvunakool, a member of the University of Cambridge team, said in a statement (via Phys.org).

So, assuming that the stipulations of general relativity are flexible, the new study from the University of Lisbon, led by Diego Rubiera-Garcia, argues that if you replace the singularity in the center of a black hole with a naked singularity, you get a finite-sized wormhole. They then took this one step further, and calculated what would happen if various objects, known as observers, made it into the wormhole.

Rubiera-Garcia and his team modeled these observers as a group of points connected by physical or chemical interactions that holds everything together as it moves. As Rubiera-Garcia explains, "Each particle of the observer follows a geodesic line determined by the gravitational field. Each geodesic feels a slightly different gravitational force, but the interactions among the constituents of the body could nonetheless sustain the body." To clarify, a geodesic line is simply a path in spacetime that a free-falling object follows.

What Rubiera-Garcia and his team demonstrated was that finite forces, no matter how strong, could compensate for the impact of the gravitational field near and inside the wormhole on a physical body travelling through it. This means that while under the theory of general relativity, an object approaching a black hole will be spaghettified, under the "naked horizon" theory, the object can only be crushed just as much as the size of the wormhole.

In a broader sense, this means that an observer could survive a journey through the wormhole and make it to the other side -potentially to another universe- though it would be crushed to the size of a finite wormhole. "For a theoretical physicist, the suffering of observers is admissible (one might even consider it part of an experimentalist's job) but their total destruction is not," said Rubiera-Garcia.

Until we are able to actually interact with black holes in more ways, all of this work remains purely hypothetical. But, along with new technology to help us take the first ever real picture of a black hole, we are slowly uncovering more and more mysteries, truths, and theories about these terrifying space phenomenon.