cosmic structure formation宇宙结构形成.ppt

The Theory/Observation connectionlecture 1the standard model Will Percival The University of Portsmouth Lecture outline The standard model (flat Lambda CDM universe) GR cosmological equations constituents of the Universe redshifts, distances Inflation Curvature The Universe is expanding Metrics The FRW metric Tensors in 1-slide General Relativity in 1-slide Einstein’s Equations Application to Cosmology Time-time component of Einstein’s equations Space-space component of Einstein’s equations Decomposing the density Evolution of energy densities Non-relativistic matter (dust) Relativistic particles Acceleration vs deceleration Dark Energy Decomposing the density The constituents of the Universe Photon energy density Photon energy density redshift Distances: comoving distance Conformal time Distances: angular diameter distance Distances: luminosity distance Inflation: motivation Inflation: motivation Inflation: motivation Inflation = early dark energy Beyond the “standard model”: curvature Beyond the “standard model”: curvature What if w≠-1? Further reading Dodelson, SLAC lecture notes (formed basis for the first part of this lecture, and a number of the explanatory diagrams). Available online at /ssi/2007/lateReg/program.htm Dodelson, “Modern Cosmology”, Academic Press Peacock, “Cosmological Physics”, Cambridge University Press For a review of the effect of dark energy see Percival et al (2005), astro-ph/0508156 Critical densities are parameteric equations for evolution of universe as a function of the scale factor a All cosmological models will evolve along one of the lines on this plot (away from the EdS solution) Constant w models Scale factor a quantifies expansion Figure from Dodelson “modern cosmology” (as are a number of the explanatory diagrams in this talk) Coordinate differences on expanding grid are comoving distances. To get a physical distance dl, from a Set of coordinate differences, use the metric. The metric for distances on the surf