Snowmass2021 Cosmic Frontier White Paper: Cosmological Simulations for Dark Matter Physics

Abstract

Over the past several decades, unexpected astronomical discoveries have been fueling a new wave of particle model building and are inspiring the next generation of ever-more-sophisticated simulations to reveal the nature of Dark Matter (DM). This coincides with the advent of new observing facilities coming online, including JWST, the Rubin Observatory, the Nancy Grace Roman Space Telescope, and CMB-S4. The time is now to build a novel simulation program to interpret observations so that we can identify novel signatures of DM microphysics across a large dynamic range of length scales and cosmic time. This white paper identifies the key elements that are needed for such a simulation program. We identify areas of growth on both the particle theory side as well as the simulation algorithm and implementation side, so that we can robustly simulate the cosmic evolution of DM for well-motivated models. We recommend that simulations include a fully calibrated and well-tested treatment of baryonic physics, and that outputs should connect with observations in the space of observables. We identify the tools and methods currently available to make predictions and the path forward for building more of these tools. A strong cosmic DM simulation program is

Snowmass2021 Theory Frontier White Paper: Data-Driven Cosmology

“…As detailed in other Snowmass contributions, the observational facilities of the next decade or two can provide tremendous insight into the nature of dark matter (e.g., [195][196][197][198][199][200][201][202][203]). However, this opportunity can only be realized with a strong theory and simulation program.…”

“…The opportunities and challenges are detailed in Ref. [199] (see also Ref. [203]), which we summarize here.…”

Snowmass2021 Computational Frontier White Paper: Cosmological Simulations and Modeling

“…Different dark matter models may require the addition of new treatments of local interactions, or may not be accessible to an N-body approach at all (as in the case of fuzzy dark matter models). For further details on the last topic, we refer the reader to a related White Paper on simulations focusing on dark matter [19].…”

“…Many of these candidates demand different simulation approaches from that of the cold dark matter (CDM) given their different properties. Below we list some examples of dark matter candidates and their related simulation demands or challenges, which are further summarized in a companion white paper focusing on cosmological simulations for dark matter physics [19].…”

Snowmass 2021 Cross Frontier Report: Dark Matter Complementarity (Extended Version)

“…Instruments, observations, and theorists that study extreme astrophysical environments should be supported as an essential means to constrain the expanding landscape of DM models and search strategies. • Numerical simulations of structure formation and baryonic physics are critical to robustly interpret observational studies and disentangle new DM physics from astrophysical backgrounds [16], the necessary condition for addressing particle physics questions about the nature of DM. HEP computational expertise and resources can be combined with astrophysical simulation expertise to rapidly advance numerical simulations of DM physics.…”