Synthetic data has come to play a starring role in studies of fundamental physics with modern cosmological surveys. By analyzing mock data that closely resembles the information received by astronomical telescopes, scientists conduct error-controlled studies of systematics, test data reduction pipelines, and develop new cosmological inference techniques.
Present-day tools are pushed to their limits by the effort to meet the needs of ongoing and near-future surveys for large volumes of accurate, realistically complex cosmological data. The CPAC group at Argonne is involved in numerous ongoing efforts to generate synthetic skies. These activities are interdisciplinary, connecting fundamental physics with high-performance computing, advanced statistics, machine learning, galaxy formation science, and observational astronomy. Our group has led the development of cosmoDC2, the flagship synthetic galaxy catalog used by LSST-DESC in Data Challenge 2; we have generated MockBOSS, a collection of mock galaxy catalogs for the BOSS survey; we have developed synthetic microwave skies for studies of the SZ signal with SPT and ACT; we are actively involved in generating mocks for the DESI survey.