Wormholes are a strange consequence of Einstein’s theory of general relativity. These “shortcuts” through the fabric of space and time may link two different locations in the universe; they may even connect two different universes together. This also leads to the possibility that wormholes can allow travel between two points in time. These strange entities have provided science fiction stories with material for many years, but there is credible physics behind wormholes. Now it seems that in theory slowly-rotating wormholes may be able to generate their own magnetic field. Could this be used to detect the presence of wormholes in our observable Universe?
In a previous Universe Today article, I found some interesting research about the possibility of observing a wormhole using sensitive radio telescopes. What’s more, an observer may be able to see the light from another part of the Universe that has travelled along the wormhole and then emitted through the wormhole’s mouth. An observer could expect to see a bubble-like sphere floating in space, with emitted light intensifying around the rim.
In a publication last month, Mubasher Jamil and Muneer Ahmad Rashid from the National University of Sciences and Technology in Pakistan investigates the properties of a slowly rotating wormhole and the effect this would have on a surrounding volume of space. Their calculations assume a cloud of charged particles (i.e. electrons) are gravitationally attracted to the entity, and as the wormhole rotates, it drags the cloud of electrons with it. This approach had already been carried out when considering the effects of a slowly rotating compact star on surrounding stellar plasma.
This gravitational effect is known as “frame-dragging”. As the wormhole is predicted to have a gravitational influence on the space surrounding it, Einstein’s general relativity predicts that space-time will be warped. The best way to visualize this is to imagine a heavy ball on an elastic sheet; the ball causes the sheet to stretch downward, in a cone-shape. If the ball is spun on the sheet, friction between the ball and elastic will cause the sheet to distort in another way, it will begin to twist out of shape. If you apply this idea to space-time (the elastic sheet), and you have a slowly rotating wormhole (the ball), distortions in space-time will have a dragging effect on the surrounding particles, causing them to spin with the wormhole.
This is where Jamil and Rashid’s paper steps in. If you have a rotating mass of charged particles, a magnetic field may be generated (as a consequence of Maxwell’s equations). Therefore, in theory, a slowly-rotating wormhole could have its own magnetic field as a consequence of the electromagnetic field set up by the motion of charged particles.
So could a wormhole be detected by instrumentation? That depends on the magnitude of the warping of space-time a rotating wormhole has on local space; the smaller the wormhole, the smaller the density of rotating charged particles. As theorized natural wormholes are expected to be microscopic, I doubt there will be a large magnetic field generated. And besides, you’d have to be very close to the mouth of a wormhole to stand the chance of measuring its magnetic field. The possibility of detecting a wormhole may remain in the realms of science-fiction for a while yet…
Source: arXiv preprint server