Science fiction is full of amazing space phenomena. Some of those phenomena have gone from theory to reality — like black holes and pulsars.
But what about wormholes?
These portals through space are littered throughout pop culture, like the TV series Star Trek: Deep Space Nine and the film Interstellar.
Theoretical physicist Ron Gamble describes the hypothetical of wormholes as a subway tube. "So let's say you're getting in on Penn Station in New York and you get off at Grand Central. But the in-between ... just like the subways going underground, the wormhole is kind of like what we call like a hyperspace," he says.
That hyperspace is what Gamble calls a fifth dimension. Think of it as an extra layer to the space-time reality we live in, composed of three dimensions of space and one dimension of time.
Space-time is described by Albert Einstein's famous equations for general relativity.
Gamble wrote his PhD on funky solutions to those equations, of which there are many — like black holes and yes, wormholes.
In theory, a wormhole would be created by connecting a blackhole (an object nothing can escape) to a white hole (the theoretical opposite of a black hole that spews objects out of it).
To understand how a wormhole could exist and act like a subway line across the universe, it's important to remember a few things. First, space-time has shape. Second, massive objects bend that shape — that bending is known as gravity.
Case-in-point: Planet Earth orbits our massive Sun. "The Earth sits in the curved surface that the Sun creates, and that's why we're being attracted to it. That is that's general relativity in a nutshell," Gamble explains. Wormholes could take advantage of that curvature of space, connecting different curved parts of space-time.
So are wormholes cursed to remain a dream of science fiction?
Gamble says that mathematically, "there is a non-zero chance that we could find a wormhole."
Finding one in nature is a different story. To keep this portal open scientists would need exotic matter or energy that behaves in ways we have never witnessed. Something that would keep the wormhole open. That has huge implications for finding one. According to Gamble, "if we find a wormhole, that means someone else created it."
But don't worry: As far as we know, these wormholes cannot be tested or created right now.
Still, Gamble says there is value in studying them. He says it could give scientists clues about the wider universe, of which humankind has only observed an estimated 5%. Wormholes could be in the other 95%.
Want to hear about more hypotheticals physicists have to confront in their work? Email us at shortwave@nprg.org to let us know — and we might turn your idea into a whole episode!
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This episode was produced by Berly McCoy and Rachel Carlson. It was edited by Rebecca Ramirez. Tyler Jones checked the facts. The audio engineer was Jimmy Keeley.
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