Physicists May Have Discovered the Protophobic Fifth Force of Nature
So far we have understood the universe in terms of four fundamental forces: gravitational, electromagnetic, and the strong and weak nuclear forces. All this can change if a recent finding by theoretical physicists at the University of California, Irvine is considered. What we are talking about here is a potential protophobic force, whose existential evidence can create a separate way of studying the dark sector, i.e. the unification of forces and dark matter.
It all started when the UCI researchers came across a mid-2015 finding by the experimental scientists at the Hungarian Academy of Sciences. The scientists were basically searching for ‘dark photon’ to further the study of the dark matter which makes up around 85 percent of the universe according to physicists. During their study, they uncovered a radioactive anomaly which indicated that a light particle around 30 times heavier than an electron may actually exist.
Back then the experimentalists made no claims whether this new force was a matter particle or a force-carrying particle because they were not sure about the particle that they had stumbled upon.
After studying the Hungarian researchers’ data and earlier experiments on the same subject, the UCI group found the new force to be neither a matter particle nor a dark photon. Hence, they came to infer that this discovery could be that of a fifth fundamental force.
As presented by the UCI group, this particle could be a ‘protophobic X boson’ instead of a dark photon. ‘X boson’ here stands for an unknown boson as none of its characteristics have been observed before. A ‘boson’ (named after Indian physicist Satyendra Nath Bose) in quantum mechanics is a fundamental particle that conforms to the Bose-Einstein statistics. Photon is one example of a boson. But unlike other electric forces which interact with electrons and protons, this new particle only interacts with electrons and neutrons.
Although the particle is not very heavy and laboratories have been equipped with energies required to create it since the 50s and 60s, the reason why it has been detected only recently is because of its weak interactions; something that the laboratories back then had not been fully equipped with to detect.
The continuous anomalies found in the results in known systems and the theoretical explanation of how this particle would interact with other systems, for which experiments are yet to be conducted, posit the occurrence of a new force-carrying particle. This is exactly how the early stages of discovery of a new and valid fundamental force would look like.
Now that various experimental groups know where to look for, given the light weight of the new particle, new breakthroughs are quite imminent, and these breakthroughs can lead to entirely new fields of study.
With this evidence, the possibilities are on the rise. This fifth force along with the other fundamental forces may give way to one more grand and fundamental force. On the basis of the understanding of the standard model of particle physics, physicists also cite the possibility of a dark sector with its own matter and forces. Once its existence is proved, this force will allow us to understand dark matter in a better way, and our current notions of the universe and its forces may well be redefined.