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What are wormholes and do they exist? – Chinglembi D., 12, Silchar, Assam, India
Imagine two cities on two opposite sides of a mountain. The people in these towns would probably have to go all the way up the mountain to visit each other. But if they wanted to get there faster, they could dig a tunnel straight through the mountain to create a shortcut. This is the idea behind a wormhole.
A wormhole is like a tunnel between two distant points in our universe that cuts the travel time from one point to the other. Instead of traveling for many millions of years from one galaxy to another, under the right conditions a wormhole could theoretically be used to reduce the travel time to hours or minutes.
Since wormholes represent shortcuts through spacetime, they could even act as time machines. You can exit one end of a wormhole at a time earlier than when you entered the other end.
Although scientists have no proof that wormholes actually exist in our world, they are great tools to help astrophysicists like me think about space and time. They can also answer age-old questions about what the universe is like.
Fact or fiction?
Scientists call the points where you would enter and exit a wormhole ‘mouths’, while they call the tunnel itself a ‘throat’. Victor Habbick Visions/Science Photo Library via Getty Images
Because of these interesting features, many science fiction writers use wormholes in novels and movies. However, scientists have been just as captivated by the idea of wormholes as writers.
Although researchers have never found a wormhole in our universe, scientists often see wormholes described in the solutions to important physics equations. Most notably, the solutions to the equations behind Einstein’s theory of spacetime and general relativity include wormholes. This theory describes the shape of the universe and how stars, planets, and other objects move through it. Since Einstein’s theory has been tested many, many times and found to be correct every time, some scientists expect that there are wormholes somewhere in the universe.
But other scientists think that wormholes cannot exist because they would be too unstable.
The constant pull of gravity affects all objects in the universe, including Earth. So gravity would also have an effect on wormholes. Scientists who are skeptical of wormholes believe that after a short time the center of the wormhole would collapse under its own gravity, unless it had a force pushing outward from inside the hole of worm to counteract this force. The most likely way to do this is to use what are called “negative energies,” which would oppose gravity and stabilize the wormhole.
But as far as scientists know, negative energies can only be created in amounts too small to counteract a wormhole’s own gravity. It is possible that the Big Bang created tiny, tiny wormholes with small amounts of negative energies at the beginning of the universe, and over time these wormholes have spread as the universe has expanded.
In this short Fusion video, a Caltech professor summarizes what wormholes are and the stability question scientists are discovering.
Just like black holes?
Although wormholes are interesting object structures to think about, they are not yet accepted in mainstream science. But that doesn’t mean they aren’t real: Black holes, which astrophysicists know abound in our universe, weren’t accepted when scientists first suggested they existed in the 1910s.
Einstein first formulated his famous field equations in 1915, and German scientist Karl Schwarzschild found a way to mathematically describe black holes only a year later. However, this description was so peculiar that leading scientists at the time refused to believe that black holes could actually exist in nature. It took 50 years for people to start taking black holes seriously—the term “black hole” wasn’t even coined until 1967.
The same could be true of wormholes. It may take some time for scientists to reach a consensus on whether or not they can exist. But if they find strong evidence pointing to the existence of wormholes, which they can do by looking at strange motions in stellar orbits, the discovery will shape how scientists see and understand the universe.
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