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The Cosmic Microwave Background (CMB): The Edge of the observable universe. Time. The History of the Universe. Start of the era of transparency (“surface of last scattering” or “edge of the observable universe”). High Energy & Temp. The Edge of the Observable Universe:
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The Cosmic Microwave Background (CMB): The Edge of the observable universe
Time The History of the Universe Start of the era of transparency (“surface of last scattering” or “edge of the observable universe”) High Energy & Temp
The Edge of the Observable Universe: As we look back in space we look back in time. We see: Light traveling from far away =from distant past Here & Now Long ago (about 14 Billion years) the Universe was so hot and dense it was opaque: The edge of the observable universe
Properties of the Edge of the Observable Universe: Similar to surface of Sun at time of emission • Today: • Only 2.726K above absolute Zero • “Microwave Radiation” (The “Cosmic Microwave Background”: CMB) • 1,000,000 times weaker than ambient radiation in a pitch dark room. Here & Now
CMB Temperature smooth to 3 Decimal places Red shifted CMB “dipole” (at the 0.1% level) Blue shifted Interpret CMB dipole as red/blue shits due to our motion and remove to get “cosmic anisotropies” Galaxy
A modern map of the “edge of the observable universe: The cosmic microwave background or CMB
Time The History of the Universe New Image of the “Last Scattering Surface” from NASA’s WMAP satellite released Feb 11 2003 High Energy & Temp
WMAP map of the “edge of the observable universe” plotted as a sphere
Note: we are really on the inside looking out WMAP map of the “edge of the observable universe” plotted as a sphere
The edge of the observable universe (from the COBE satellite) The Galaxy Temperature fluctuations (one part in 100,000)
CMB Temperature smooth to 3 Decimal places Red shifted CMB “dipole” (at the 0.1% level) Blue shifted Interpret CMB dipole as red/blue shits due to our motion and remove to get “cosmic anisotropies” Galaxy
NASA’s MAP(Microwave Anisotropy Probe) -Launched June 30 ’01 -Reached “L2” Oct 1 ’01 -April 1 ’02 First scanning of entire sky complete
Observing the Microwave Background, Past, present and future:
WMAP map of the “edge of the observable universe” plotted as a sphere
Note: we are really on the inside looking out WMAP map of the “edge of the observable universe” plotted as a sphere
Using the CMB to learn about the Universe Amount of “blobs” Size of blob (small ==>) solid=inflation model dashed=defect models (magenta=desperate attempt to produce sharp peak)
WMAP • Characteristic oscillations in the CMB power Inflation Temperature Power “Active” models Adapted from Bennett et al Feb 11 ‘03 Angular scale I.1 Successes
NASA’s WMAP(Microwave Anisotropy Probe) -Launched June 30 ’01 -Reached “L2” Oct 1 ‘01
WMAP • Characteristic oscillations in the CMB power Inflation Temperature Power “Active” models Adapted from Bennett et al Feb 11 ‘03 Angular scale I.1 Successes
Maps of the microwave sky (the “edge of the observable universe”) Real 1993 2009 Simulated 2003 Simulated
Maps of the microwave sky (the “edge of the observable universe”) Real 1993 Updated after WMAP announcement, Feb 2003 2009 Real Data! 2003 Simulated
Maps of the microwave sky (the “edge of the observable universe”) Real 1993 Updated after WMAP announcement, Feb 2003 2009 Real Data! 2006 Simulated
Cosmic acceleration Using supernovae (exploding stars) as cosmic “mileposts”, acceleration of the Universe has been detected. Preferred by modern data Amount of “antigravity” matter “Ordinary” non accelerating matter Supernova Amount of ordinary matter
Cosmic acceleration Using supernovae (exploding stars) as cosmic “mileposts”, acceleration of the Universe has been detected. Preferred by modern data Amount of “antigravity” matter “Ordinary” non accelerating matter Supernova Amount of ordinary matter
Cosmic acceleration Accelerating matter is required to fit current data Preferred by data c. 2003 Amount of w=-1 matter (“Dark energy”) “Ordinary” non accelerating matter Supernova Amount of “ordinary” gravitating matter
Cosmic acceleration Accelerating matter is required to fit current data Kowalski, et al., Ap.J.. (2008) Preferred by data c.2008 Amount of w=-1 matter (“Dark energy”) “Ordinary” non accelerating matter BAO Supernova Amount of “ordinary” gravitating matter