The Study Of Kaluza-klein Particle Mass And Influence Of Extra Dimensions On Helium Abundances

In this thesis,we study the cosmological properties in the Kaluza-Klein gravitational model,the cosmological solutions with AdS3(?)S1(?)S3(?) S3 compactification of superstring and the cosmological solutions with D4 (?)M1(?)S5 compactillcation of chiral supergravity are obtained,the physical significance of these solutions is also discussed.In the Vl=R(?)S3(?)formal compactification,the corrected values of radion mass are calculated when the inner sphere space is deformed,the corrected spectra of radion mass in 1-sphere space deformation and 2-sphere space deformation are given,the influence of space dimensions and deformed parameters on radion mass is analyzed.The fluctuation equations of scale factor in 1-sphere and 2-sphere compactification are derived,it is proved that the fluctuation of the inner sphere space is the physical origin of radion mass generation.Moreover,the value of Helium abundance in the universe is calculated according toMukhanov’s modified reaction rate expression.When the extra dimension space exists,the modified equilibrium equation is deduced by using the change relation of the fine coupling constant α,the weak interaction coupling constant Gw and the gravitational coupling constant G.At the same time,the correction values of Helium abundance in the universe are calculated when the extra dimension d changes.When the change of the extra dimension scale factor is taken as the ε=10 2,10 3,the Helium abundance values are calculated respectively from d=2 to d=11.In addition,the Helium abundances values are also calculated if extra dimensional scale factor is oscillation varying with time,the results show that there has been some change of the Helium abundances values when the change of the extra dimension scale factor is taken as theε=10-2,the variation of Helium abundance is not obvious if change of the extra dimension scale factor is taken as the ε=10-3.The innovative work in this thesis is as follows:1.For the first time,the corrected values of radion mass are calculated when the inner sphere space is deformed,the correction spectra of radion mass in 1-spherical space deformation and 2-spherical space deformation are given.The fluctuation equations of scale factor in 1-sphere and 2-sphere compactification are derived,it is proved that the fluctuation of the inner sphere space is the physical origin of radion mass generation2.When the extra dimension space exists,the modified equilibrium equation is deduced by using the change relation of three coupling constants,the correction values of Helium abundances in the universe are calculated when the extra dimension d changes.In addition,the Helium abundance values are also calculated if extra dimensional scale factor is oscillation varying with time.