1. Cosmology Overview David Spergel

2. Lecture Outline  THEME: Observations suggest that the simplest cosmological model, a homogenuous flat universe describes the universe on its largest scales I.General Relativity: Dynamics and Shape of the Universe II.Metric Theory III.Evidence for Isotropy IV.Tests of Metric Theories V.Open Questions and Future Observations

3. General Relativity: A Review  Space is not absolute. Only relative positions are meaningful.  Matter tells space how to curve  Curvature of space tells matter how to move: particles move on “straight lines”

4. Metric Theory

5. Particles move on straight lines NEWTONIAN LIMIT:

6. Matter Distribution determines curvature of space Riemann Tensor: Unique combination of second derivatives of metric Ricci tensorCurvature Scalar Einstein Equation Newtonian limit of Einstein equation

7. GR from Least Action Principle Least Action: Once you start adding terms, there may be no stopping: e.g., Carroll et al., astro-ph/0413001 What is this doing here?

8. Big Bang Cosmology Homogeneous, isotropic universe (flat universe) Freidmann Equation

9. Pseudo-Newtonian Cosmology Differentiate Friedmann equation: where

10. Homogeneous & Isotropic Universe

11. Homogeneity

12. Isotropy

13. MAP990045 Microwave Receiver The Cosmic Microwave Background  and y distortion constraints CMB is not a grey body! Not a sum of black bodies!

15. Density fluctuation versus scale

16. Quasar Correlation Function

17. Evolution of Scale Factor Matter: Radiation Vacuum Energy

18. Conformal Structure of Space-time

19. Redshift

20. Supernova Duration Goldhaber et al. (2001) ApJ 558, 359

21. Molaro et al. (2002) Expansion of the universe cools microwave background CI thermometer

22. Hubble Law Krisciunas, Phillips and Suntzeff (2004) ApJL 602:81

23. Rulers and Standard Candles Luminosity Distance Angular Diameter Distance

24. Supernova

25. Flat M.D. Universe D = 1500 Mpc for z > 0.5

26. Volume

27. Measuring Distances

28. Closed Universes

29. Distance Measurements

30. The universe appears to be remarkably simple in its geometry if not its composition