Einstein’s Theory of General Relativity allows wormholes to be a possibility. But no one has ever observed a wormhole yet. Black holes were theorised to exist as a result of General Relativity, and later observed as our tech improved. Our own Milky Way has one at the center called Sagittarius A*. Wormholes however, remain elusive – which relegates wormholes slightly towards the realm of science fiction. Just the spacetime ones though, because physicists have now managed to create ‘magnetic’ wormhole.
To understand a magnetic wormhole and its significance, we need an understanding of general spacetime wormholes.
The Physics of a Wormhole
Albert Einstein and Nathan Rosen proposed the wormhole concept in 1935 using General Relativity. A wormhole is a ‘bridge’ that connects two different regions of space-time across the universe. Imagine two blackholes connected to teach other – you get sucked in via one end and eject through the other. That’s a wormhole.
A wormhole is therefore, a very convenient way to achieve faster-than-light speeds to traverse the universe. Interstellar did its part popularising the concept to a mass audience.
You can travel long or short using wormholes. Additionally, you can also travel into the past or into the future using a wormhole. But all this is theoretical. No wormhole has been observed yet, and our math (and Stephen Hawking) tells us wormholes are likely to be highly unstable anyway. We’re centuries, maybe millennia away from exploiting wormholes as a space faring race, if that is even possible.
To compensate until then perhaps, physicists have created something else – a magnetic wormhole. Mind you, this involves no space-time travel. A magnetic wormhole is well, simply the magnetic equivalent of a spacetime wormhole. We cannot travel in between space-time, but we can transfer magnetic fields from one point of space-time to another. Just like a wormhole, physicists have been able to move or transfer magnetic field from one region of space-time to another. Researchers in the Autonomous University of Barcelona, Spain have transferred a magnetic field across space using a superconducting tube. There is a catch though, the external field can interact and distort the field inside the tube. Therefore, we need make it invisible to other fields. Scientists have to ‘cloak’ the tube.
(Image taken from New Scientist)
According to a report in the Scientific American. The researchers used ‘metamaterials’ that interact with electromagnetic fields in uncommon approaches. If we understand these ‘metamaterials’ completely, there’s potential to manufacture cloaks that are invisible to light (Predator-1987 anyone?). A shell is made of a high-temperature superconductor that bends the magnetic lines of force. While the outermost shell is a mu-metal that perfectly cancels out the bending of magnetic fields. The metamaterials makes the whole arrangement magnetically invisible. Essentially, when the field pops out in other region of the space-time, it should look like a magnetic monopole.
Magnetic wormholes are a purely artificial creation. They operate on entirely different principles compared to spacetime wormholes – making their natural occurrence rather unlikely. They remain incredibly useful, however. Discussions on their potential industrial applications are already ongoing, and there are plenty of ideas.
Wormholes fit rather beautifully in MRI scanning technology. We could tunnel the magnetic field from one corner of the room to the other corner; thereby scanning the human body with magnets placed far way will reduce the risk of MRI scans to great extent.
Scientists are working to use the technology using various geometries. Right now, they have experimented using a sphere (the most basic geometrical shape). We’re also looking at methods that allow us to exploit magnetic wormholes in other geometries. Apparently, a cylinder would be the most productive. We could also use this technology in tight places where we there is a need for huge magnetic fields.
We can’t estimate with any certainty how far off we are from discovering (or exploiting) spacetime wormholes. But magnetic wormholes? Check.