Inflationary Parameters and Swampland Conjectures in Various Scenarios of Gravity

Abstract

The purposeofthisthesisistoinvestigatethein°ationaryparameters and swamplandconjecturesinthepresenceofscalar¯eldandChaplygin gas models.Weinvestigatethein°ationaryparameterssuchasslowroll parameters, scalarpowerspectrum,tensorpowerspectrum,spectralin- dex, tensor-to-scalarratiointhepresenceofscalar¯eldandChaplygingas modelsandalsodiscusstherecentlyproposedswamplandconjectures.The in°ationary scenarioisassumedtobeworkingunderastandardscalar¯eld having¡asdecayratio.Thisdecayratiohasdependenceintheformof generic power-lawofscalar¯eld Á along withthermalbathtemperature T, that is,¡(Á; T) = CÁ Ta Áa¡1 , where CÁ is dimensionlessparameterand a is in°ation decayrate.Assumingthatourmodelbendsaccordingtostrong dissipativeregime(R À 1), westudythebackgroundandperturbativedy- namics aswellasin°ationaryobservableasthescalarpowerspectrum PR, scalar spectralindex ns, dissipativeratio R, thetensor-to-scalarratio r, run- ning ofthescalarspectralindex dns d ln k and generalizedratioofSwampland de-Sitter conjecture ¶ TV ¶ V T for threedi®erentpotentials V (Á) = 3H2inf 8¼ e 2Á p(Á+1) , V = M4µ Á Mp¶2µ1 + ¯ Á2 M2p ¶ and V = 3 4M2(1 ¡ ep 2 3Á)2 respectively.