Looking for lost antimatter in Los Alamos

Wouter Dekens , PhD student at the Van Swinderen Institute of the University of Groningen, will be able to conduct research fort wo years at the Los Alamos National Laboratory in the USA thanks to the Rubicon grant awarded by the Netherlands Organisation for Scientific Research (NWO). Wouter Dekens will be studying the possible asymmetry between matter and antimatter.

The NWO Rubicon programme enables young talented researchers to acquire international research experience at a top institute abroad to help kick-start their academic careers. A total of 97 applications for Rubicon grants were submitted to NWO in this round, of which 21 were approved.

Lost antimatter

The research Wouter Dekens will be conducting in Los Alamos is entitled ‘ A window on the universal matter-antimatter asymmetry’. With the Big Bang both matter and antimatter were released. Yet, it is unknown to us why the Universe of today contains matter and hardly any antimatter. This might be explained by an asymmetry between matter and antimatter particles occurring shortly after the Big Bang. However, such a scenario is not covered by the elementary particles theory. At the Los Alamos National Laboratory Dekens will use state-of-the-art measurements to find out whether the asymmetry scenario is feasible.

On October 16^th, Wouter Dekens will defend his thesis ‘ Discrete symmetry breaking beyond the standard model’ in the Aula of the Academy Building.

Abstract Rubicon project Wouter Dekens

A window on the universal matter-antimatter asymmetry

The existence of matter in the present-day universe derives from a tiny imbalance between matter and antimatter, generated shortly after the Big Bang. This asymmetry requires violation of CP, the symmetry between particles and antiparticles. Currently, the most successful theory describing elementary particles, does not violate CP strongly enough to generate the matter-antimatter imbalance. Therefore our very existence calls for unknown CP-violating physics. Discovering this uncharted territory is paramount to understand why there is something rather than nothing.

A host of cutting-edge experiments, ranging from high-precision measurements at low energies to the ultra-high-energy proton collisions at CERN, aim to discover additional CP violation. Such a ground-breaking discovery would naturally raise the question: Which new-physics scenario is responsible? For this purpose, I aim to develop new measurement strategies to distinguish between such scenarios, and derive constraints from the experimental results. I will focus on interactions involving the recently discovered Higgs boson, which could itself be significantly CP-violating and thereby essential to understand the matter-antimatter imbalance.

Furthermore, I will derive quantum Boltzmann equations necessary to describe the build-up of the matter-antimatter asymmetry in new-physics scenarios. This will ultimately allow one to determine whether such scenarios can correctly predict this still unexplained asymmetry.