Up until the early 1900s, Newton’s theory of gravity held supreme. It was the idea that all objects in the Universe—including you and me—have an innate force within us that attracts other objects. The larger an object, the greater this intrinsic gravitational pull. This explains why we “stick” to the Earth instead of flying off into space.
But in 1915, Albert Einstein completely tore that idea apart. He theorized that gravity is actually the result of a warping in spacetime (a combination of space and time into one continuum). Essentially, an object’s very existence deforms space and time around itself, creating an imprint on the universe.
And it’s this deformation of space-time that gives rise to gravity’s effects. “Suppose that there’s you and another mass. You deform the spacetime around you and the mass deforms the space-time around it, and you’re both falling into each other’s wells,” says Richard Holman, a physics professor at Carnegie Mellon University.
Now here's the part where this all ties into wormholes. According to Einstein and his colleague Nathan Rosen, a wormhole is actually deformed space that has warped in such a way to connect two different points in space-time. The result is a tunnel-like structure that could be straight or curved, linking two areas of the Universe that are incredibly far apart.
Einsteinian mathematical models predict that wormholes exist, but none have ever been found. Fumio Abe, an astrophysicist at Nagoya University, has proposed a way to search for large wormholes (big enough for a spaceship) by looking at a star’s brightness when it moves in front of the tunnel. An effect called gravitational lensing would cause the brightness to fluctuate in a unique way.