Cosmology and particle astrophysics

We work in an interdisciplinary area which involves particle physics, field theory, astrophysics, fluid dynamics, and cosmology. In the past five years, we have spent efforts in the following directions:

1. Interacting dark energy. Recent astrophysical and cosmological observations have predicted dark energy, which constitutes 70% of the total mass of the Universe and provides an anti-gravity force to accelerate the cosmic expansion. We investigate the cosmological consequences of the interaction of dark energy with dark matter or electromagnetism, which give rise to CMB birefringence B-mode polarization and other cosmological effects.

2. Primordial gravitational waves and primordial black holes. We study the production of primordial black holes and associated gravitational waves in inflationary cosmology. These primordial black holes can be a candidate for dark matter and the gravitational waves can be detected by future gravity-wave experiments.

   Researchers: Kin-Wang Ng, Shu-Lin Cheng, Un Pang Chang, I-Tai Ho