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What Was Before the Big Bang? Framework Space-Time Cosmology of the Very Early Universe Std Early Universe R. Branden- berger Cosmology What was before the Big Bang? Framework Space-Time Cosmology of the Very Early Universe Std. Cosmology Inflation String gas Robert Brandenberger Conclusions McGill University February 21, 2013 1 / 68 Outline Early Universe R. Branden- berger 1 What is Cosmology? Cosmology Framework 2 Space-Time Framework Std. Cosmology Space-Time Inflation Standard Big Bang Cosmology String gas Conclusions 3 Inflationary Cosmology 4 String Cosmology 5 Conclusions 2 / 68 Plan Early Universe R. Branden- berger 1 What is Cosmology? Cosmology Framework 2 Space-Time Framework Std. Cosmology Space-Time Inflation Standard Big Bang Cosmology String gas Conclusions 3 Inflationary Cosmology 4 String Cosmology 5 Conclusions 3 / 68 Goals of Early Universe Cosmology Early Universe R. Branden- berger Cosmology Framework 1. Understand origin and early evolution of the universe. Space-Time Std. Cosmology What is the “Big Bang"? Inflation Was there a “Big Bang"? String gas Conclusions What was before the “Big Bang"? 2. Explain observed large-scale structure. 4 / 68 Goals of Early Universe Cosmology Early Universe R. Branden- berger Cosmology Framework 1. Understand origin and early evolution of the universe. Space-Time Std. Cosmology What is the “Big Bang"? Inflation Was there a “Big Bang"? String gas Conclusions What was before the “Big Bang"? 2. Explain observed large-scale structure. 4 / 68 Goals of Early Universe Cosmology Early Universe R. Branden- berger Cosmology Framework 1. Understand origin and early evolution of the universe. Space-Time Std. Cosmology What is the “Big Bang"? Inflation Was there a “Big Bang"? String gas Conclusions What was before the “Big Bang"? 2. Explain observed large-scale structure. 4 / 68 Goals of Early Universe Cosmology Early Universe R. Branden- berger Cosmology Framework 1. Understand origin and early evolution of the universe. Space-Time Std. Cosmology What is the “Big Bang"? Inflation Was there a “Big Bang"? String gas Conclusions What was before the “Big Bang"? 2. Explain observed large-scale structure. 4 / 68 Goals of Early Universe Cosmology Early Universe R. Branden- berger Cosmology Framework 1. Understand origin and early evolution of the universe. Space-Time Std. Cosmology What is the “Big Bang"? Inflation Was there a “Big Bang"? String gas Conclusions What was before the “Big Bang"? 2. Explain observed large-scale structure. 4 / 68 Optical Telescopes: Gemini Telescope Early Universe R. Branden- berger Cosmology Framework Space-Time Std. Cosmology Inflation String gas Conclusions 5 / 68 Galaxies: Building Blocks of the Cosmology Early Universe R. Branden- berger Cosmology Framework Space-Time Std. Cosmology Inflation String gas Conclusions 6 / 68 Large-Scale Structure Early Universe R. Branden- berger Cosmology Framework Space-Time Std. Cosmology Inflation String gas Conclusions From: talk by O. Lahav 7 / 68 Microwave Telescopes on the Earth: ACT Telescope Early Universe R. Branden- berger Cosmology Framework Space-Time Std. Cosmology Inflation String gas Conclusions 8 / 68 Microwave Telescopes on the Earth: SPT Telescope Early Universe R. Branden- berger Cosmology Framework Space-Time Std. Cosmology Inflation String gas Conclusions 9 / 68 Microwave Telescopes in Space: WMAP Telescope Early Universe R. Branden- berger Cosmology Framework Space-Time Std. Cosmology Inflation String gas Conclusions 10 / 68 Isotropic CMB Background Early Universe R. Branden- berger Cosmology Framework Space-Time Std. Cosmology Inflation String gas Conclusions 11 / 68 Anisotropies in the Cosmic Microwave Background (CMB) Early Universe R. Branden- berger Cosmology Framework Space-Time Std. Cosmology Inflation String gas Conclusions Credit: NASA/WMAP Science Team 12 / 68 Quantification of the CMB data Early Universe R. Branden- berger Cosmology Framework Space-Time Std. Cosmology Inflation String gas Conclusions Credit: NASA/WMAP Science Team 13 / 68 Goals of Early Universe Cosmology Early Universe R. Branden- berger 1. Understand origin and early evolution of the universe. Cosmology What is the “Big Bang"? Framework Space-Time Was there a “Big Bang"? Std. Cosmology What was before the “Big Bang"? Inflation String gas Conclusions 2. Explain observed large-scale structure. Patterns in the distribution of galaxies on large scales. Anisotropies in CMB maps. 3. Make predictions for future observations. 14 / 68 Goals of Early Universe Cosmology Early Universe R. Branden- berger 1. Understand origin and early evolution of the universe. Cosmology What is the “Big Bang"? Framework Space-Time Was there a “Big Bang"? Std. Cosmology What was before the “Big Bang"? Inflation String gas Conclusions 2. Explain observed large-scale structure. Patterns in the distribution of galaxies on large scales. Anisotropies in CMB maps. 3. Make predictions for future observations. 14 / 68 Plan Early Universe R. Branden- berger 1 What is Cosmology? Cosmology Framework 2 Space-Time Framework Std. Cosmology Space-Time Inflation Standard Big Bang Cosmology String gas Conclusions 3 Inflationary Cosmology 4 String Cosmology 5 Conclusions 15 / 68 Framework Early Universe R. Branden- The Universe is: berger Space-time Cosmology Framework Matter which lives in space-time. Space-Time Std. Cosmology To describe the Universe: Inflation String gas Space-time described by Einstein’s theory of General Conclusions Relativity. Matter as described by Physics. More specifically: matter described on large scale by classical physics, on small scales by quantum mechanics and on even smaller scales by superstring theory? 16 / 68 Framework Early Universe R. Branden- The Universe is: berger Space-time Cosmology Framework Matter which lives in space-time. Space-Time Std. Cosmology To describe the Universe: Inflation String gas Space-time described by Einstein’s theory of General Conclusions Relativity. Matter as described by Physics. More specifically: matter described on large scale by classical physics, on small scales by quantum mechanics and on even smaller scales by superstring theory? 16 / 68 Framework Early Universe R. Branden- The Universe is: berger Space-time Cosmology Framework Matter which lives in space-time. Space-Time Std. Cosmology To describe the Universe: Inflation String gas Space-time described by Einstein’s theory of General Conclusions Relativity. Matter as described by Physics. More specifically: matter described on large scale by classical physics, on small scales by quantum mechanics and on even smaller scales by superstring theory? 16 / 68 Framework Early Universe R. Branden- The Universe is: berger Space-time Cosmology Framework Matter which lives in space-time. Space-Time Std. Cosmology To describe the Universe: Inflation String gas Space-time described by Einstein’s theory of General Conclusions Relativity. Matter as described by Physics. More specifically: matter described on large scale by classical physics, on small scales by quantum mechanics and on even smaller scales by superstring theory? 16 / 68 Framework Early Universe R. Branden- The Universe is: berger Space-time Cosmology Framework Matter which lives in space-time. Space-Time Std. Cosmology To describe the Universe: Inflation String gas Space-time described by Einstein’s theory of General Conclusions Relativity. Matter as described by Physics. More specifically: matter described on large scale by classical physics, on small scales by quantum mechanics and on even smaller scales by superstring theory? 16 / 68 Framework Early Universe R. Branden- The Universe is: berger Space-time Cosmology Framework Matter which lives in space-time. Space-Time Std. Cosmology To describe the Universe: Inflation String gas Space-time described by Einstein’s theory of General Conclusions Relativity. Matter as described by Physics. More specifically: matter described on large scale by classical physics, on small scales by quantum mechanics and on even smaller scales by superstring theory? 16 / 68 Framework Early Universe R. Branden- The Universe is: berger Space-time Cosmology Framework Matter which lives in space-time. Space-Time Std. Cosmology To describe the Universe: Inflation String gas Space-time described by Einstein’s theory of General Conclusions Relativity. Matter as described by Physics. More specifically: matter described on large scale by classical physics, on small scales by quantum mechanics and on even smaller scales by superstring theory ? 16 / 68 Framework Early Universe R. Branden- The Universe is: berger Space-time Cosmology Framework Matter which lives in space-time. Space-Time Std. Cosmology To describe the Universe: Inflation String gas Space-time described by Einstein’s theory of General Conclusions Relativity. Matter as described by Physics. More specifically: matter described on large scale by classical physics, on small scales by quantum mechanics and on even smaller scales by superstring theory ? 16 / 68 Space-Time as Described by General Relativity Early Universe R. Branden- berger Cosmology Framework Space-Time Std. Cosmology Space-time dynamical (no longer absolute like in Inflation Newtonian theory) String gas Conclusions Matter curves space-time. 17 / 68 Space-Time as Described by General Relativity Early Universe R. Branden- berger Cosmology Framework Space-Time Std. Cosmology Space-time dynamical (no longer absolute like in Inflation Newtonian theory) String gas Conclusions Matter curves space-time. 17 / 68 Mass curves Space-Time Early Universe R. Branden- berger Cosmology Framework Space-Time Std. Cosmology Inflation String gas Conclusions 18 / 68 Space-Time as Described by
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