CoStaMM · Cosmological phase transitions of Standard Model Matter and their gravitational wave signatures

The Standard Model of particle physics is the theory of the strong, electromagnetic and weak interactions, describing the elementary particles of nature at microscopic length scales. The precise theoretical predictions of the Standard Model are put to the test in contemporary and future high-energy particle collider experiments. Besides explaining matter around us in the present, the Standard Model also predicts the distant past of our Universe, by describing the behavior of particles at temperatures as high as it used to be just fractions of seconds after the Big Bang. The relics of the cosmological phase transitions in this era of our Universe are actively soughtfor via their gravitational wave signatures in current and future observatories. Most of the relevant features of hot Standard Model matter are non-perturbative, implying that a first-principles treatment is only possible via computer simulations of the underlying field theories on space-time lattices. This proposal will use such large-scale lattice field theory simulations to determine the properties of cosmological phase transitions and thus significantly improve our understanding of how the early Universe cooled down and became the world that we know today.Specifically, we will perform the first full physical simulations of hot, electrically charged strongly interacting matter. We will also substantially improve on existing calculations of the weak and electromagnetic interactions at high temperature. The computational effort of the combined treatment of these forces is immense – we will overcome these challenges by employing optimized algorithms and cutting-edge technologies including machine learning methods. For both systems, we will determine the nature of the high-temperature transition and analyze the induced gravitational wave spectrum. Our results will provide the most accurate description of Standard Model matter in the early Universe.