Galaxies and Cosmology Key figures in relativistic cosmology Friedman de Sitter Einstein Lemaitre
General Relativity
The Galaxy
The Galaxy
Distances SMC by Fred Espenak
The Expanding Universe
The Expanding Universe Hubble and Humason, 1931
The Steady State
The Less Rapidly Expanding Universe... part 1 MB = -4.35 log P + 3.98 MB = -1.33 log P + 0.24 MB = -2.59 log P - 0.67 W Vir stars (Type II Cepheids) – magnitude of about -1 at log P = 1 m – M = 5 log(d/10) If ΔM = 2, d changes by factor of 102/5 = 2.5 Classical (Type I) Cepheids – magnitude of about -3 at log P = 1
The Less Rapidly Expanding Universe... part 2 red plate; H II regions marked blue plate; star marked Allan Sandage, ApJ 127 (1958) 123
Hubble’s (not-very) Constant Sandage recognises HII regions (not stars) Jan Oort Baade discovers Pop II
Radio Source Counts
Cosmic Background Wilkinson Peebles Dicke Herman – Gamow – Alpher Wilson Penzias Wilkinson Peebles Dicke
Cosmic Background Boynton, Stokes & Wilkinson, 1968 COBE satellite, 1990
Big Bang Nucleosynthesis Wagoner, Fowler and Hoyle (1967)
Hubble Wars Gerard de Vaucouleurs Allan Sandage
Hubble Peace?
Hubble Peace?
Inflation
CMB Anisotropies David Spergel