We aim to understand the universe and exploit it as an ultimate laboratory to explore fundamental physics.
We have been bombarded with UNKNOWNS from cosmology since the end of the 20th century. They are about:
1. Initial condition of the universe: INFLATION does a great job.
2. Cosmic structure: Structure formation requires extra attractive gravity, probably from DARK MATTER, an unknown energy source of (attractive) gravity.
3. Cosmic expansion: The late-time accelerating expansion requires anti-gravity (repulsive gravity), probably from DARK ENERGY or MODIFIED GRAVITY, i.e., an unknown energy source of anti-gravity or unknown modification of the gravity law.
Another unknown is from particle physics:
4. NEUTRINO OSCILLATION and NEUTRINO MASS: They play a role not only in particle physics, but also in cosmology concerning cosmic structure formation.
We attempt to unravel these unknowns. Our research can be divided into three subjects: