First theorized in 1935 by Albert Einstein and as part of the theory of general relativity, wormholes were originally known as "Einstein-Rosen bridges," and are thought of as holes through space-time. Although there's math that can prove they exist, they've never been created or spotted anywhere in the universe.
However, scientists at the Autonomous University of Barcelona have created a magnetic wormhole that appears to transfer a magnetic field through "an extra special dimension." Magnetic wormholes aren't space-time wormholes, but they work in a similar way: space-time wormholes are a manipulation of gravitational energy, whereas magnetic wormholes are a manipulation electromagnetic energy.
Using metamaterials the scientists were able to create a tunnel of magnetic energy last year. This year, they made the tunnel invisible. Space-time wormholes connect two points in the universe through an unseen bridge, but this wormhole connects two magnetic fields through an unseen bridge.
A normal magnet has two poles-- north and south, with a magnetic field connecting them. In this case, their wormhole separated the poles, singling them out, creating a monopole, which is something that does not happen in nature. Researchers can't tell where the magnetic field that connects those monopoles is, which gives the illusion it's in a "special dimension." This device makes a monopole pop into existence, with no detectable connection to that pole on the other side.
A 2007 study in Physical Review Letters made headlines when it manipulated electromagnetic energy to create an "invisibility cloak," and that is essentially what these Spanish researchers have done. This wormhole can't move anything from one place to another or through time. It doesn't really do anything super practical at the moment, but it may be a proof-of-concept for some exciting future technology.
“Wormholes are fascinating cosmological objects that can connect two distant regions of the universe. Because of their intriguing nature, constructing a wormhole in a lab seems a formidable task.”
“The metal sphere lets one magnetic field pass through another undetected, which could lead to improvements in medical imaging.”