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B.SadouletHubble Phys 24 2011 1
The Big Bang and the Hubble Constant
Where are we? Where are we coming from?MapsDynamics
The Hubble ConstantDistance ladder
B.SadouletHubble Phys 24 2011
Where are
Toutes les grandes civilizations se sont posées cette question.
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Map from Tupaia drawn by Cook 1769from The Trial of the Cannibal Dog: The Remarkable Story of Captain Cook’s Encounters in the South Seas, Anne Salmond, Yale University Press, 2003
Carte de Tupaia tracées par le Capitaine Cook 1769from The Trial of the Cannibal Dog: The Remarkable Story of Captain Cook’s Encounters in the South Seas, Anne Salmond, Yale University Press, 2003
B.SadouletHubble Phys 24 2011
Pratical Importance of AstronomyRemarkable precision: Importanceof astronomy for Polynesian sea farers
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Maps of directions, winds and waves
B.SadouletHubble Phys 24 2011
Our Place in the Universe
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B.SadouletHubble Phys 24 2011
Statute of Creation Stories
Very sophisticated mix ofFactsPractical informationQuestions about originInter-relationshipsMeaning and harmony
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Modern ScienceFactsPractical information: technologyTheoretical paradigmSome relationships
butSilent about meaning, harmony
B.SadouletHubble Phys 24 2011
Modern View
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B.SadouletHubble Phys 24 2011
The Milky Way and Beyong
Are Nebulae(=galaxies) inside or outside the Milky Way ≈ 1925?
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Curtis
Shappley
B.SadouletHubble Phys 24 2011
We are at the Edge of the Milky Way
Infrared image of our galaxy (Dirbe 2000)
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B.SadouletHubble Phys 24 2011
Cosmological Maps
SLOAN Digital Sky Survey
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B.SadouletHubble Phys 24 2011
Telescope Hubble (2004)
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B.SadouletHubble Phys 24 2011
Cosmic Microwave Background
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B.SadouletHubble Phys 24 2011
Reversing Perspective
The further away we observe, the earlier we in the age of the
Strong evidence that convergence to a point: The Big Bang
3 pillarsThe Hubble expansionRelic radiation ≈ 3000K: The Cosmic Microwave
BackgroundNuclear furnace => formation of light elements
In homogeneous, isotropic expect
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Georges Lemaître
B.SadouletHubble Phys 24 2011
The Hubble Expansion
Wrong by a factor 713
MountWilson
B.SadouletHubble Phys 24 2011
Distance Ladder
Basic idea: standard candle
We have to go very far not to be disturbed by infall
e.g. Andromeda1000 Million light years
Calibrate objects locally and work one’s way upEarthSolar system (Transit of Venus, radar)Parallax of stars in galaxy (Hipparcos)CepheidsSupernovae or calibrated galaxies
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B.SadouletHubble Phys 24 2011
An Historical Parenthesis
Transit of Venus 1769Lieutenant Cook
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B.SadouletHubble Phys 24 2011
Modern Determination
Distance LadderHubble TelescopeCepheids
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arXiv:astro-ph/0012376. 2001ApJ...553...47F
Latest valueA. Reiss et al. arXiv:1103.2976v1 [astro-ph.CO] 15 Mar 2011 H0 = 73.8 ± 2.4 km s−1 Mpc−1
