World View of the Universe

Based on Hubble's law and the CMBR, our world view of the Universe is rather firm. On the assumption that our interpretation that v = H(now) x D is due to an uniform expansion of the Universe is true, models have been constructed for the Universe based on Einstein's General Theory of Relativity (GR). Einstein himself made models for the Universe (circa 1910-1920's). Unfortunately, Einstein was led astray because he believed in a homogeneous, isotropic, and static Universe (on philosphical grounds).

• in a gravitating Universe, a static solution is not possible because gravity is always attractive, i.e., it always tries to pull things closer together
• to get around this tendency to contract, Einstein postulated the existence of a large-scale repulsive force which would counteract gravity on large distances
• this force is paramtrized by what is referred to as The Cosmological Constant (represented by the Greek letter capital Lambda)

When Hubble's result became known (1929), Einstein immediately withdrew his suggestion of a Cosmological Constant as there was no need for a large-scale repulsive force in a non-static Universe. However, note that today, the idea of a Cosmological Constant has been resurrected.

I will first view the Universe from a theoretical slant:

• General solutions

  (plus a physical interpretation of the GR results in terms of Newtonian physics)

• Realistic evolutionary scenarios

• Speculation about the first 10**(-43) seconds

I will then direct my attention to more observational issues (with implications for theory):

• Large-scale structure in the Universe ====> Life