ASTR 160 - Frontiers and Controversies in Astrophysics
Lecture 20 - Dark Matter. This lecture introduces an important concept related to the past and future of the universe: the Scale factor, which is a function of time. With reference to a graph whose coordinates are the Scale factor and time, the problem of dark matter is addressed again. Cosmological redshifts are measured to determine the scale of the universe. The discovery of the repulsive, anti-gravitational force of dark energy is explained. The lecture concludes with discussion of Einstein's biggest mistake: the invention of the cosmological constant to balance gravity. (from oyc.yale.edu)
| Lecture 20 - Dark Matter |
| Time | Lecture Chapters |
| [00:00:00] | 1. The Scale Factor |
| [00:04:41] | 2. Accounting for Dark Matter in Mass of Universe |
| [00:27:58] | 3. Discovery of Dark Energy |
| [00:42:06] | 4. Understanding Dark Energy and Einstein's Biggest Mistake |
| References |
| ASTR 160: Lecture 20 - Dark Matter Instructor: Professor Charles Bailyn. Class Notes Lecture 20 [pdf]. Problem Set 7 and Solutions [pdf]. Transcript [html]. Audio [mp3]. Download Video [mov]. |
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