Newtonian and Friedmann-Robertson-Walker cosmology

Cosmology (Winter, 2009)

January 19, 2009

In this lecture Prof Susskind starts with the concepts of Newtonian cosmology.  Discuss the extent to which Newtonian cosmology can extend our understanding of cosmology.  Prof Susskind discusses the connections with the F=ma within cosmology.  This lecture discusses the Friedman- Robertson Walker FRW equations of cosmology. We further cover some cosmological geometry. Further study some dynamics of cosmology.  Study how the scale factor change with time. How the universe expands.  Discuss what equations drive the expansion. Study in detail the Friedmann-Robertson-Walker (FRW) equations. Prof Susskind derives the form of Newton’s equation.  Prof Susskind starts with the idea of flat space.  Discuss the assumptions that the universe is homogenous and isotropic.  Prof Susskind further discusses the application of Hubble’s law.  We further discuss that the Hubble’s constant is not static, but rather dynamic and how it changes with time.  Prof Susskind further discusses how space can be flat yet the space-time can be curved. Prof Susskind introduces the discussion of what is dark energy, what is dark matter, and the cosmological constant.  Prof Sussking discusses why physicist think there is a lot more matter than what we can see. We further discuss the possibilities of K = + / - / 0 .  Where K =0 implies flat space.