Presentation on theme: "3A03 – GR and Cosmology Ralph Pudritz Dept. of Physics & Astronomy McMaster University."— Presentation transcript:
3A03 – GR and Cosmology Ralph Pudritz Dept. of Physics & Astronomy McMaster University
Hubble Space Telescope – time machine This telescope has enabled our deepest probe at optical wavelengths, of the cosmos – the Hubble “deep field”.
Looking back in time – galaxies long ago This image, consists entirely of galaxies. Very faint ones are at cosmological distances: -smaller and “blotchier” than galaxies at present. -Evidence for for galactic evolution over cosmic time.
Mapping where galaxies are – “large scale structure” Da Costa et al (1994) (Center for Astrophysics survey ) - 9,325 galaxies shown - The largest structure yet seen: the “Great Wall”.
THE ORIGINS OF STRUCTRE IN THE UNIVERSE How did galaxies form? - Density fluctuations infinitesimal in size, originate from quantum fluctuations in spacetime soon after the Big Bang. - These are seen in fluctuations in CMBR – baby photo of galaxies!