age of the universe albert einstein anisotropy arno allan penzias astronomy and astrophysics boomerang experiment big bang big bang nucleosynthesis big crunch binary icosahedral group carl friedrich gauss closed manifold closed set compact space constant curvature cosmic gravitational wave background cosmic inflation cosmic microwave background radiation cosmic neutrino background dark energy earth edwin hubble ekpyrotic euclidean geometry euclidean space fifth dimension fluid dynamics frame of reference franz taurinus friedmann equations fundamental group future of an expanding universe galaxy filament galaxy formation and evolution geodesic geodesic manifold geometrization conjecture geometry george gamow george smoot hubble volume hyperbolic geometry icosahedral symmetry infinity klein bottle lambda-cdm model large-scale structure of the cosmos light cone manifold metric expansion of space multiplicative inverse observable universe observational cosmology physical cosmology picard horn pseudosphere pythagorean theorem radius redshift relativity of simultaneity riemannian manifold robert woodrow wilson simply connected space sloan digital sky survey special relativity spherical geometry stephen hawking structure formation theorema egregium theory of relativity timeline of cosmology timeline of the big bang topology torus ultimate fate of the universe universe vera rubin wilkinson microwave anisotropy probe