陳丕燊 Pisin Chen
Illuminating the Darkness
於幽暗處覓光明
Abstract:
The past two decades have seen dramatic progress in cosmology, the study of the large scale universe. After the revolutions in physics made in the 20th century, we suddenly realized, entering the new century, that 95% of the substance in the universe is made of the dark matter and the dark energy, the nature of which we know very little.
The explanation of these, especially that of the dark energy, necessarily touches the foundation of physics. Aside from these issues, we note that the universe is full of extremely high energy particles, such as neutrinos. The detection of those may help us resolve many additional mysteries, including the origin of the ultra-high energy cosmic rays and the challenge of Einstein's basic assumption in special relativity, that is, whether the speed of light at very high energies remains constant. In this talk I will give an overview of the outstanding puzzles in cosmology and how physicists have been trying to solve them. Thus far the progress is still modest and there are ample chances for the future generations of physicists to further contribute in illuminating the darkness in the universe.