Scientists are on the hunt for a ‘dark force’ of nature that could reveal the universe that lies hidden from view. Through this hunt, scientists expected to get a deep insight into the fundamental forces that associates the ordinary matter of the world around us and the invisible ‘dark sector’.
Though there are fewer chances of success, if found, it would rank among the most dramatic discoveries in the history of physics, predicted scientists.
All the stars, planets and galaxies that can be seen today make up just 4 percent of the universe. The other 96 percent is a mystery made up of dark matter, and the even more baffling dark energy.
Mauro Raggi, a researcher at the Sapienza University of Rome said, “At the moment, we don’t know what more than 90% of the universe is made of. If we find this force it will completely change the paradigm we have now. It would open up a new world and help us to understand the particles and forces that compose the dark sector.”
Despite the apparent complexity within the universe, there remain just four basic forces: Gravitational force, Electromagnetic force, Weak nuclear force, Strong Nuclear Force. These forces are responsible for all interactions known to science.
But, according to scientists, there may be other forces that have gone unnoticed. Such forces may be responsible for the behaviour of the so far unknown particles that constitute dark matter, and could potentially exert the most subtle effects on the forces we are more familiar with.
This month, Raggi and his colleagues will turn on an instrument at the National Institute of Nuclear Physics near Rome which is designed to hunt down a possible fifth force of nature. The instrument named PADME is a new experiment aiming to seek this type of event through the accurate reconstruction of the missing mass in the balance between the initial state, constituted by the electron-positron pair (using the positrons of the Beam Test Facility) and the final state in which only the ordinary photon is detected.
The Padme experiment will run until at least the end of the year, but there are tentative plans to move the instrument to Cornell University in 2021. There it would be hooked up to a more powerful particle accelerator than in Italy to broaden its search for dark photons.
The dark photon, if it exists, would have an imperceptible influence on what makes up the world we see. But knowing its mass, and the kinds of particles it can break down into would provide the first glimpse of what makes up the bulk of the universe that is beyond our perception.
Bryan McKinnon, a research fellow at Glasgow University said, “The dark photon if it exists, is effectively a portal. It lets us peer into the dark sector to see what is happening. It won’t open the floodgates, but it will allow us to have a little look.”