Astr 1050     Wed., Dec 3, 2003

The Hubble Law and the Age of the Universe
Ho = 72 ±8 km/s/Mpc

Hubble Law:  Everyone sees same expansion

Universal Expansion: Balloon Analogy

Early History of Universe?
Run time “backwards” to understand

Consider a molecular H2 , He gas as it gets hotter

Critical points with time running forward

First prediction from Big Bang model:
Cosmic Background Radiation

Cosmic Microwave Background Observations

Second prediction from Big Bang Model:
Abundance of the light elements

Main Tests of the Big Bang

Will the expansion stop?

General Relativistic Description

Mass and the Curvature of Space

How to test the amount of curvature

How high is the density?

Refining the Big Bang

Implications of Slowing Expansion Rate

Is the expansion rate slowing?

Measuring deceleration using supernovae

“Cosmological constant”

Tests using
 the Origin of Structure

Acoustic Peaks in Background

Cosmology
 as a testing ground for physics

Chapter 15: Cosmology