Astr 328 Mar 17, 2003: Observational cosmology  

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The flatness problem

The early universe is flat

SNIa experiment (cont)

Nagging details

Photometric systems

K correction

K correction is a function of galaxy type

K correction for SNe?

Supernova cosmology project

CfA high-z supernova search

Looks like we are stuck with lambda

Expansion dynamics

Exponential expansion for Lambda-dominated epoch

Plot of different options for expansion rate

Lookback times are extended

What did we do for standard candles before SNIa?

Used brightest cluster member

Other cosmological tests

Tests based on a standard rod

Use of RW metric in this case

angular size of rod

Define angular size distance

How angular size changes with z

What are some possible standard rods for use in cosmology?

Extragalactic radio sources??!!

Galaxy clusters??!!!

Distances in Cosmology article