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The Curvature of Space. The Isotropic and Homogeneous Universe. What does curved space look like?. The Expansion of the Universe. The Doppler Effect. Galaxy Spectra are Redshifted. Edwin Hubble (1889-1953). Hubble Diagram (1929). V = H r H ~ 500 km/s / Mpc (first measurement!).
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The Curvature of Space The Isotropic and Homogeneous Universe What does curved space look like?
Edwin Hubble (1889-1953) Hubble Diagram (1929) V = H r H ~ 500 km/s / Mpc (first measurement!)
Cosmological expansion Expansion causes wavelength of light to increase - REDSHIFT For distant galaxies, distance is proportional to redshift – related by the Hubble constant Redshift surveys = measuring the redshifts of many galaxies… distance and look-back time 13 to 14 Gyr (billion yrs) = age of Universe
Cosmic expansion Comoving coordinates remain the same