The Standard Model, the main theory of particle physics, worked perfectly in predicting at a theoretical level what experimental physics could then observe, thanks to technological marvels such as the LHC, on the blocks that constitute matter. However, the theory is still incomplete: the Two Higgs Doublet Model hypothesis could perhaps be the right way to fill a gap.The Standard Model of particle physics is the theory that tries to explain the structure of the infinitely small of the universe as a whole. According to this vision, matter and antimatter were formed in equal quantities, with the Big Bang.
The Standard Model
The Standard Model is a model that has the function of describing both matter and the forces of the universe. In fact, this model describes the particles that constitute all the matter we know and three of the four fundamental forces observed in nature: the electromagnetic and the weak interaction (unified in the so-called electroweak interaction) and the strong one. Gravity at the moment remains outside, this is one of the reasons why the standard model can not be considered complete and definitive. However strong it may be, the Standard Model does not seem to be able to explain the current situation of the Universe, both for the problem of gravity and for the prevalence of matter on antimatter.
But what is Antimatter?
Nothing transcendental, antimatter is nothing but matter, only endowed with opposite electric charge, this characteristic means that if two particles, for example an electron and a positron (which is the antiparticle of the electron, an electron with a positive charge) come into direct contact, they annihilate, being reduced to nothingness in a catastrophic event that produces pure energy. It is believed that matter and antimatter were originally present in equal quantities.
Which method can be used to solve a similar problem?
One possibility is to hypothesize (and then try to find) new particles that can explain discrepancies, as in the case of the hypothesis known as Two Higgs Doublet Model (2HDM), which would like to add four particles to the Standard Model. At the moment it seems that this idea is in keeping with the observations made thanks to CERN’s LHC, the currently largest and most powerful particle accelerator in the world.
Along this path, a large group of researchers from different universities (from Norway, Finland, the Netherlands and the USA) has proposed to tackle the problem from a different point of view. It all starts from the hypothesis, so far confirmed by most scientists, that ten picoseconds after the Big Bang, while the Universe was only plasma, took shape the Higgs boson. At this point the team of researchers has applied the scientific method of dimensional reduction to try to reduce the number of variables and simplify the problem.
According to David Weir, physicist at the Institute of Physics in Helsinki, Finland, doing so they replaced the theory that describes the plasma with a simpler theoretical model. This model wants all the particles to follow a set of rules and shows that the heaviest particles do not undergo alterations under these rules. So the hypothesis seems valid, and it is less complicated to manage. Computer models of this approach have allowed these scientists to have a scenario that explains what could have happened when the Higgs boson appeared and what determined the asymmetry between matter and antimatter, using the Higgs hypothesis. A result of considerable interest, because this complex work demonstrates that, having established a set of rules, it is possible to explain the absence of antimatter in the Universe. In any case, if the Higgs boson has ignited so violently as the hypothesis on which the team’s work is based, it would have had to leave an echo in the plasma, which in turn would have produced gravitational waves. Now the researchers will have to look for those gravitational waves to cofirm their hypotheses, and they will do it thanks to the LISA project.