An important discovery in science in the past few decades is most mass and energy in the universe is dark. These clever forms of matter and energy are capable of speeding up the motion of stars and galaxies and the expansion of the universe, while eluding direct detection at the same time.
This lecture will provide a summary of the evidence for the existence of dark matter and dark energy, what it can and cannot be, and the ongoing research on these mysterious components of the universe.
在過去的幾十年中，科學上的一項重大發現是：宇宙中的大部分物質和能量是黑暗的。這些以機靈方式存在的物質和能量，能加速星球和星系的運動以及宇宙的膨脹，同時又規避了我們的直接偵測。
本演講將摘要地提供暗物質和暗能量存在的證據，它會是什麼和不會是什麼，以及針對這些宇宙的神祕成分，目前正在進行中的科學研究。
宇宙的碰撞
Cosmic Collisions
The universe is a dynamic place. The building blocks of the universe -- galaxies -- are not isolated, static islands of stars, gas, and dark matter. Rather, they collide with one another and merge to form larger galaxies.
During this process, the supermassive black holes lurking at the centers of galaxies can also coalesce into bigger black holes. This lecture will present highlights of current observations of galaxy mergers and discuss theoretical studies using supercomputer simulations to understand these cosmic collisions.
