暗能量_2011.ppt

Dirac Cosmology and the Acceleration of Contemporary Universe Ru-Keng Su Fudan University, Shanghai,China Introduction Unified Theory of G.R. and Dirac Cosmology Numerical Solution with Matter and Radiation Solar System Test Summary and Discussion Introduction 1 Large number hypothesis The large dimensionless numbers provided by atomic physics and astronomy of our universe connect with each other the ratio of the electric to the gravitational force between an electron and proton the age of the universe expressed in the atomic unit Introduction 2 The mass of that part of the universe that is receding from with a velocity v c/2, expressed in the unit of proton mass Introduction 3 B Difficulties How to explain the contradiction between G.R. and Dirac cosmology Milne two time scale hypothesis Weyl’s geometry… All experiments at the scales of solar system and galaxies have not found the variation of G Introduction 4 The conservation of energy and momentum in local system Dirac suggested: Addition creation: the new matter creates uniformly in whole space Dark Energy? Multiplication creation: the new matter creates in the regions where the old matter exists Dark Matter? Introduction 5 Can we establish a possible unified theory of Dirac cosmology and G.R.? R.K. Su, S.W. Zhang, Proc of the 3rd Grassmann Meeting on G.R. P.1381 1983 ; Acta. Math. Sci. 3 1983 321; Kexue Tongbao Sci. Bullium of China 27 1982 944. Introduction 6 Basic idea: Though one would expect a constant value of G at the local system, it must be stressed that the cosmological observations still cannot put strong limits on the time variation of G in the cosmological scale Though Einstein G.R. has been proved to be correct by many experiments at the scales of local systems, it probably needs to be modified in the cosmological scale. Introduction 7 Local sys tem, , R , 0 Cosmological scale, matter dominate area , 1/2 Introduction Local system , Cosmological scale Di