3 ms·
> why we suppose there has to be dark matter and energy in the universe. PBS Space Time has a set of short videos[1] that do a very good job of explaining dark
by pdkl95 10y ago
> why we suppose there has to be dark matter and energy in the universe.
PBS Space Time has a set of short videos[1] that do a very good job of explaining dark {matter,energy}. It starts with Einstein's field equations and GR, then walks through what the Friedmann equations say about the expansion of the universe.
[1] https://www.youtube.com/watch?v=xZTb6sfHEX8 https://www.youtube.com/watch?v=xZTb6sfHEX8 (and the next few videos: https://www.youtube.com/pbsspacetime/videos https://www.youtube.com/pbsspacetime/videos )
- dwaltrip 10y agoFor those who haven't seen yet any of the PBS Space Time videos and are interested in physics and cosmology, it is really well done. I recommend checking it out. Each episode is pretty short, entertaining, and jam packed with well explained information. I'm now hooked on the series, and feel like I am more informed about our latest understanding of physics and the universe.