The Universe today is old, cold, low-density, and expanding. If we run
the expansion backwards, we will eventually find a Universe where all
the matter was in one place where the density and temperature are nearly
infinite. We call this hot, dense initial state of the Universe the Big
Bang. This lecture introduces the Big Bang model of the expanding
univ ... Show More
Jun 2009
Telescopes that Rocked Our World
This year marks the 400th anniversary of Galileo’s use of the first telescope. On this week’s show, we reflect on how telescopes have shifted our perspective on how small we are in size, space, and time. We also discuss how they help astronomers discover new and interesting aspec ... Show More
56 m