Einstein’s equations deem wormholes theoretically possible—but so far, we haven’t been able to prove they exist.
Now, though, a group of scientists has fashioned a wormhole prototype out of a material commonly used in the fringeinvisibility cloak industry . Alvaro Sanchez of the Universitat Autònoma de Barcelona, lead author on a study just published in Scientific Reports , says they’ve built a device that, if put inside a magnetic field, will be magnetically undetectable. If a magnetic field travels through the device, the magnetic field disappears from space completely and pops out the other side, similar to the way a wormhole bends space-time so that two distant locations become connected. This creates the illusion of a magnetic monopole, a hypothetical object that does not truly exist in nature.
To make the wormhole, Sanchez transferred a magnetic field across space using a length of metal tubing. Then his team surrounded the tube with two layers of material, one superconducting and one ferromagnetic. Since superconductivity and ferromagnetism do not mix well together, the combination effectively renders the magnetic field inside the contraption invisible. The result is what’s called a metamaterial—an artificial type of matter that behaves according to the properties of the materials that make it up and the subtle ways they’re put together.
When the scientists tested the wormhole, they saw that as the magnetized cylinder moved through their new device, the magnetic field “seemed to wink out, only showing at the mouths of the wormhole,” as Jesse Emspak reported for Smithsonian . “While the cylinder wasn’t traveling faster than light, it was moving unperturbed and unseen between two regions of space, invoking the image of a classical wormhole.”
The study shows that you can shield magnetic fields so that they don’t interfere with one another—and that could have some astounding applications.
Here’s Joshua Sokol, writing for New Scientist:
Being able to cloak magnetic fields as they travel across space could help build better MRI scanners, Sanchez says. Wormholes could let multiple magnetic imagers work together without interfering with each other, or could be used to put some distance between bulky sensors and patients—all without changing the background magnetic field MRIs rely on. His team is planning to reach out to local doctors to guide future research.
The magnetic wormhole is an impressive demonstration of the power of metamaterials, Lassas says. “It makes the scientific work on invisibility cloaking a step—or in fact, a leap—closer to real life applications.”