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Published byBasil Wheeler Modified over 5 years ago
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Outline Part II. Structure Formation: Dark Matter
5. Linear growth of fluctuations by gravitational Instability 6. Statistics of fluctuations: initial fluctuations and the cold-dark-matter scenario 7. Nonlinear growth of structure: spherical collapse, virial equilibrium, Zeldovich approximation and the cosmic web, N-body simulations 8. Hierarchical clustering: Press-Schechter halo distribution, EPS merger trees, galaxy/halo biasing, HOD and correlation function 9. Dark-matter halos: universal profile, the cusp/core problem, dynamical friction, tidal effects, halo shape 10. Substructure of dark-matter halos, phase-space density
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Outline cont. Part III. Galaxy Formation: Including gas and Stars
11. Angular momentum: tidal-torque theory, halo spin, disk formation, the AM problem 12. Galaxy bimodality: observations, virial shock heating, star formation and quenching mechanisms, downsizing 13. Dwarf galaxies and supernova feedback 14. Formation of elliptical galaxies by mergers: missing dark matter? origin of scaling relations, origin of red sequence and downsizing 15. Galaxy formation at high redshift: cold streams, clumpy disks and compact spheroids 16. Massive black holes in galaxies: AGN feedback 17. Semi-analytic modeling of galaxy formation
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Linear Growth of Fluctuations by Gravitational Instavility
2dF WMAP
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2dF Galaxy Redshift Survey ¼ M galaxies 2003
1/4 of the horizon CFA Survey 1980
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History Early Universe Cosmic Microwave Background Today time
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Cosmological Epochs recombination last scattering
380 kyr z~1000 recombination last scattering CMB transparent optical opaque: “dark ages” 180 Myr z=8.81.5 first stars reionization galaxy formation: optical transparent → see galaxies today 13.8 Gyr
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Gravitational instability
small-amplitude fluctuations: gravitatinal instability: galaxy cluster void
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גידול הפלקטואציות - המארג הקוסמי
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Gravitational Instability: linear, matter-era
Continuity Euler Poisson
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gravity pressure
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pressure gravity
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Properties of the linear growing mode:
The Jeans scale in an expanding universe:
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Statistics of Fluctuations:
Lecture Statistics of Fluctuations: The Cold Dark Matter Scenario
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The Initial Fluctuations
At Inflation: Gaussian, adiabatic a realization of an ensemble fluctuation field ensembe average ~ volume average Fourier Power Spectrum rms M δ k Pk
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Scale-Invariant Spectrum (Harrison-Zel’dovich)
mass M t time M
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Cosmological Scales mass teq zeq~104 t0 time
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growth when matter is self-gravitating
CDM Power Spectrum mass t time teq growth when matter is self-gravitating Meq mass CDM Pk kpeak m h k CDM HDM HDM free streeming
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Formation of Large-Scale Structure
Fluctuation growth in the linear regime: rms fluctuation at mass scale M: Typical objects forming at t: example M 1 CDM: bottom-up M 1 free streaming HDM: top-down
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Micro-Macro Connection
Cold Dark Matter Hot Dark Matter
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2dF redshift survey 25% of horizon
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2dF and Mocks
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Power Spectrum
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Success of the LCDM Power Spectum
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