Shengqi Yang is interested in understanding galaxy evolution and star formation environments at high redshift, in particular the galaxy assembly era z~3 and the epoch of reionization at redshift higher than 6. Studying the physical properties of galaxy interstellar medium (ISM) is a key step to achieve this goal because ISM hosts star formation activities and stores information about the galaxy formation history. She is developing first principle models for strong ISM tracers, including CII and OIII fine structure emission lines, to interpret ISM properties from recent ALMA measurements in a physics-grounded manner. Another emerging technique that probes ISM over wide cosmic volume is line intensity mapping (LIM). Yang is developing empirical sub-millimeter line emission models, cosmological mocks, and foreground removal techniques to assist LIM survey forecasts.

Yang is also interested in studying the interplay between the host and satellite dark matter halos, and further probe the nature of dark matter with semi-analytic models and simulations.