Changing Gears: The Big Picture

Cosmology

Where are the Galaxies: Structure of the Universe

• cosmological principle: homogeneous & isotropic
• actual data: 2dF Galaxy Redshift Survey
  • survey geometry
  • maps: slices of the cosmos here, here, and here
  • results in 3-D

Galaxy Motion Relative to Us

• Hubble's law: orignal paper, modern update
• Hubble motion: artist's conception

The Expansion of the Universe

• demanded by homogeneity and isotropy
• scale factor
• raisin cake analogy
  balloon analogy

The Center of the Universe?

• demands of homogeneity and isotropy
• alternative location: a short drive southwest of campus
  Philo, IL: downtown landmark, zoom

The Future: Fate of the Universe

• Traditional view: gravity vs intertia
• New data: cosmic acceleration
• interpretations: dark energy or downfall of General Relativity?