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ASTR 2010 Cosmology. Week 14: Lecture 36 (26 Nov. 2012) The Big Bang. The “Big Bang” Cosmology:. Observations: - Hubble Expansion: V= HD t U ~ 1 / H ~ 13.7 x 10 9 yrs.
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ASTR 2010 Cosmology • Week 14: • Lecture 36 (26 Nov. 2012) • The Big Bang
The “Big Bang” Cosmology: Observations: - Hubble Expansion: V= HD tU ~ 1 / H ~ 13.7 x 109 yrs. Space expands (gravitationally unbound systems only!) - Elemental abundances: 30% of H => He in first minutes of Big Bang All other elements s ~1- 2 % by mass made in stars) - Cosmic Microwave Background (CMB) Radiation left over from a Hot Big Bang Universe is “flat” => Has critical density !
Distance vs. redshift => Accelerating expansion! • Type Ia • Supernovae • Standard candles • Nuclear detonation • 1.4 Mo white dwarf • ~ 1051 ergs
fainter brighter
Perlmutter, Riess, Schmidt (1998 +)- Dark energy (2011 Nobel Prize)
General relativity & Cosmology Alexander Friedmann: Scale factor evolution & cosmic geometry : a(t) depends on density
Omega ordinary matter = 0.04 Omega darkmatter = 0.23 Omega matter = 0.27 Omega = [density] / [critical density]
Omega dark energy = 0.73 Omega total = 0.04 + 0.23 + 0.73 = 1.0
The Fate of the Visible Universe • Hubble constant: expansion rate NOW • DARK MATTER: pulls expansion curves down • DARK ENERGY: pushes expansion curves up
The “Big Bang” Cosmology: Observations: - Hubble Expansion: V= HD tU ~ 1 / H ~ 13.7 x 109 yrs. Space expands (gravitationally unbound systems only!) - Elemental abundances: 30% of H => He in first minutes of Big Bang All other elements s ~1- 2 % by mass made in stars) - Cosmic Microwave Background (CMB) Radiation left over from a Hot Big Bang Universe is “flat” => Has critical density !
ASTR 2010 Cosmology • Week 14: • Lecture 37 (28 Nov. 2012) • The Big Bang - 2
Lambda-Cold Dark Matter (-CDM) Cosmology Time Space
Cosmology topics to be covered: - Black holes, worm holes, & Singularities: non-rotating, rotating - White holes, enthropy, & the arrow of time. Time reversal in singularities? - Inflation: Higgs field: false vacua, origins of mass, Higgs mechanism - Matter-antimatter asymmetry - Quark-gluon plasma => P, n, => H, He => stars & stellar nucleosynthsis - Acoustic oscillations, radiation pressure vs. gravity, “BAO” - CMB formation: Harmonics in the CMB: Roles of dark matter - Dark ages - Galaxy formation, evolution, cosmic structure formation - Fate of the Cosmos - String theory: Cosmic dimensionality - Multiverses: Type I, II, III, OIV (Tegmark classification) - Cosmic “Natural Selection & Reproduction” (Smolin & Darwinian evolution) - Black holes and cosmic reproduction: Roles of dark energy - Origin and fate of life. - The Anthropic principle: Why is the Universe friendly to life? - Engineering the next Universes: The Smolin-Harrison cosmology
The “Big Bang” Cosmology: Theory: - General Relativity (gravity) Friedmann Equation: Cosmic Evolution depends on density ofmatter + energy Space expands (gravitationally unbound systems only!) Emergence from a compact (ultra dense) state: From a singularity similar to one in a black hole? Planck-scale: 10-33 cm 10-43 sec 10-5 g 1094 g cm-3 - Quantum mechanics & particle physics: (electromagnetism, weak force, strong force + matter & energy) Matter Bosons (force carriers): photons, W+, W-, Z0 , gluons, gravitons Fermions (“matter”): electrons, quarks (neutrons, protons) Dark matter ? - “super-symmetry”? Dark energy ? - Vacuum energy (Einstein’s Cosmological constant, )?
ASTR 2010 Cosmology • Week 14: • Lecture 38 (30 Nov. 2012) • The Big Bang - 2
Quantum Mechanics: Relativistic Quantum Field Theory : All matter & energy are waves: E= h = hc / = mc2 = h / mv non-relativistic (V <<c) = h / mv relativistic: V ~ c; = 1 / (1 - v2 / c2)0.5 Energy <=> mass Symmetries:matter <=> anti-matter: Charge symmetry neutral neutral charge <=> opposite charge For h511keV:hhe-+e+ 1 eV = 1.6 x 10-12 erg For h1 GeV:hhp++p- Super-Symmetry:bosons <=> fermions (at > 1013 eV) Bosons (force carriers):photons (h, W+, W-, Z0, gluons, gravitons || | || | EMweak forcestrong gravity Fermions (“matter”):electrons, quarks (neutrons, protons), neutrinos Dark matter ? - photinos, neutralinos, selectons, squarks …. ?
Large Hadron Collider (LHC) Geneva, Switzerland
Large Hadron Collider (LHC) vacuum tubes in tunnel
Large Hadron Collider: TeV (1012 eV) proton - proton collision [u+2/3 u+2/3 d-1/3] <=> [u+2/3u+2/3 d-1/3] => u+2/3, d-1/3, s+2/3, c-1/3, t+2/3, b-1/3 =>short-lived particles => p+, n, e-, h,
Large Hadron Collider: TeV (1012 eV) proton - proton collision Example: top, bottom quarks => decay to p+, n, e-, h,
The “Big Bang” Cosmology: Theory: - Friedmann Equation: Cosmic Evolution depends on density ofmatter + energy Space expands (gravitationally unbound systems only!) Emergence from a compact (dense) state: A singularity as in a black hole? - The “Lambda Cold-Dark-Matter” (-CDM) cosmology Ultra-hot energy emerges from singularity 10-33 sec Inflation 10-26 sec Matter-antimatter asymmetry (matter dominates!) 10-3 sec Quark-gluon condensate 10-1 sec neutrons, protons 1 sec nucleosynthesis 300 sec Atomic Hydrogen + CMB 3.8 x 105 years Stars + galaxies ~3 x 108 years
Omega ordinary matter = 0.04 Omega darkmatter = 0.23 Omega matter = 0.27 Omega = [density] / [critical density]