Remember the Big Bang? How the universe came to be? Well, there’s a lot we don’t understand about it. One being–the Big Bang should have produced matter and antimatter in equal quantities and immediately after, the two would annihilate each other and all that would have been left is light. Which means, we should not have existed.
Yet, we do exist. Along with a whole lot of matter and very little antimatter. So, what happened? Where did all that antimatter go? That is one of the biggest unsolved mysteries in Physics.
The recent discovery of a “left-handed” magnetic field across the universe could help explain that mystery, a group of scientists, led by Tanmay Vachaspati from Arizona State University with collaborators at Washington University and Nagoya University announced in their findings.
Vachaspati earlier published theoretical models to try to solve this puzzle, which predict that the entire universe is filled with helical (screw-like) magnetic fields. He suggested that even if matter and antimatter were created in equal amounts at the Big Bang, as they annihilated each other, they would have briefly created monopoles and antimonopoles–hypothetical particles with just one magnetic pole, north or south.
When these monopoles and antimonopoles in turn annihilated each other, they would produce matter and antimatter. But there is a quirk in the laws of physics, known as CP violation, which favors matter and leaves the universe biased toward matter. If that were true, the event would result in the matter-filled world of today.
Vachaspati also said that if that were the case, there would be evidence of it today. He and his team looked for the evidence of these fields in data from the NASA Fermi Gamma-ray Space Telescope.
The Fermi observes gamma rays from distant sources, like the supermassive black holes in distant galaxies. Gamma rays are sensitive to the magnetic field they travel through. On their way to Earth, if they cross a field that is helical, it will imprint a spiral pattern on the distribution of gamma rays.
Vachaspati and his team see such imprints in the Fermi data. There is not only a helical field, but that there is an excess of left-handedness—which might be an indication of why antimatter is absent.
However, there are more mysteries to be solved and questions to be answered, as in why the left-handedness is more that expected, whether the magnetic field could be caused by other events, and whether the CP violation could support the abundance of matter we see in the universe today.