Particle Physics: What We Know We Don’t Know
It is the job of particle physicists to identify the fundamental building blocks of matter, learn their properties, and describe how they talk to one another. In spite of fantastic progress over the past several decades, there is still much we don’t understand. This evening, hosted online by the Aspen Center for Physics, Professor de Gouvêa will discuss some of the big questions – and there are only a few of them – that remain unanswered. He will concentrate on two puzzles: Why do neutrinos have nonzero masses? What is most of the universe made of?
Prof. de Gouvêa received his BSc and MA degrees at the Pontifícia Universidade Católica do Rio de Janeiro and his PHD from the University of California, Berkeley. He concentrates his research efforts on theoretical high-energy physics, more specifically on the phenomenology of the physics that lies beyond the standard model of particle physics.
Two concrete facts reveal there are phenomena to which there is no well-defined answer. First, there is the very strong, albeit indirect, evidence that most of the mass of the Universe is contained in the form of ‘dark matter.’ Equally strong is the evidence that the dark matter is not made up of any of the fields of the standard model (baryons, neutrinos). It is hence very likely that new fields, with unknown properties and interactions exist.
Second, it is established, beyond reasonable doubt, that neutrinos have non-zero masses. Non-zero neutrino masses are not allowed in the textbook version of the standard model, but can be accommodated in a variety of different ways if the model is modified. Most of de Gouvêa’s research efforts are concentrated on exploring, in different ways, these two known evidences of physics beyond the standard model.
