Einsteins Static Universe 1917 De Sitters Accelerating Universe

Einstein’s Static Universe (1917)

De Sitter’s Accelerating Universe Always expanding exponential curve R = exp[t /3] No matter – only It has no beginning and no end (1917) Willem De Sitter 1872 -1934

Friedmann’s universes 1922, 1924 1888 -1925

Edwin Hubble (1889 -1953) Hubble-Humason Law today Milton Humason (1891 -1972)

The Einstein-de Sitter Universe ‘I do not think the paper very important myself, but de Sitter was keen on it’ Einstein =0 1932 ‘the paper by Einstein and myself I do not myself consider the result of much importance, but Einstein seemed to think It was’ De Sitter

Lemaître's Universe 1927 The best description of the visible universe today >0

Tolman’s Oscillating Universe Richard Tolman and Einstein at Cal Tech 1932

Tolman includes the 2 nd Law of thermodynamics: Oscillations grow (1932) JDB + Dabrowski include the cosmological constant: Oscillations always end (1995)

Kasner’s Anisotropic Universe Volume abc time 1921 Edward Kasner (1878 -1955)

expansion shear rotation

Gödel's Rotating Universe Allows time travel to occur ! 1949

Real Universes Tend to Get Lumpy Is this the origin of galaxies ? Newton 1693 Jeans 1902 Lifshitz 1946

The Big Bang Universes

The Evidence of a Hot Early History

The Inflationary Universe A temporary lambda 1981

Even Smaller Beginnings

Chaotic Inflation Geography is more complicated than we thought

Eternal Inflation 77 10 More than 10 by-universes from our patch alone

The Universe is Accelerating Again >0 Lemaître's universe describes our visible universe to high precision

The Return of Lambda ? ?