Shedding Light on Dark Matter (part 4)

Shedding Light on Dark Matter (part 4) In the fall I'm giving a lecture series on topics ranging from the history of the universe to time travel. Dark Matter is one of those topics. In this final part of the series, we go over a very brief history of Dark Matter and some of its competitor theories, such as Modified Newtonian Dynamics (MOND) and Massive Compact Halo Objects (MACHOs).