Alumnae and Alumni

Hideki Tanimura
Position
Project Researcher (from 2022/10/01 to 2024/03/31)
Current Affiliation
Office for Enhancing Institutional Capacity, Hokkaido University
Research Administrator

PHOTO

Last Update 2024/04/08

The aspect of cosmology that attracts me the most is the prospect that we can use the universe as a laboratory to learn about fundamental physics. The existence of dark matter and dark energy clearly point to physics beyond the Standard Model of particle physics, though we are far from understanding what that physics is. Upcoming cosmological observations are likely to test it.

The evolution of large-scale structure, from its very simple gaussian initial conditions to the magnificent cosmic web, poses many challenges to our understanding. On the very largest scales, the evolution is relatively simple, but as we drill down to smaller scales, structures become nonlinear and baryonic physics begins to become important. One of the key tracers of the large-scale structure are clusters of galaxies: these objects are the most massive bound systems in the universe and they roughly mark the transition from the simple larger scales to the more complicated smaller scales. Baryonic physics is known to play an important role in the evolution of cosmic structure from roughly cluster scales "to smaller scales", but observational probes of baryonic gas on these scales are difficult to come by. One such probe is the Sunyaev-Zel'dovich (SZ) effect: the inverse Compton scattering of CMB photons by free electrons along the line of sight. A key feature of the SZ effect is that its strength is independent of the redshift of the scattering gas, making it a powerful probe of gas evolution. The primary focus of my research is to study the properties of gas in the large-scale structure using the SZ effect as a tracer.


Back to Member List.