Constraining the variable generalized Chaplygin gas model in matter creation cosmology  

作　　者：Yogesh Bhardwaj C P Singh 

机构地区：[1]Department of Applied Mathematics,Delhi Technological University,Bawana Road,Delhi-110042,India

出　　处：《Communications in Theoretical Physics》2024年第10期119-134,共16页理论物理通讯（英文版）

摘　　要：We explore the variable generalized Chaplygin gas(VGCG)model in the theory of matter creation cosmology within the framework of a spatially homogeneous and isotropic flat Friedmann—Lemai tre—Robertson—Walker space-time.Matter creation cosmology is based on reinterpretation of the energy–momentum tensor in Einstein's field equations.This creation corresponds to an irreversible energy flow from the gravitational field to the created matter constituents.The variable Chaplygin gas(VCG)is also studied as a particular solution.We use the Markov chain Monte Carlo method to constrain the free parameters of three models,namely,Lambda-Cold-Dark matter(ΛCDM),VGCG and VCG models with and without matter creation from the latest observational data from baryon acoustic oscillations,cosmic chronometer,type Ia supernovae(Pantheon)including gamma-ray bursts,quasars and the local measurement of H_(0) from R21 data.Two different combinations of dataset provide a fairly tight constraint on the parameters of theΛCDM,VGCG and VCG models.The present values of various cosmological parameters are obtained,which are very close to theΛCDM model.Furthermore,we perform stability analysis,Bayesian evidence analysis and information criteria analysis for these models through studying the sound speed,Bayes factor,and Akaike information criteria(AIC)and Bayesian information criteria(BIC)selection criteria.The values of sound speed for VGCG and VCG models shows that both the models are stable.According to AIC,it is observed that VGCG and VCG models with matter creation are supported considerably less by current observations,while BIC shows that these models are not favoured by observational data.

关 键 词：cosmological model matter creation Chaplygin gas model dark energy 

分 类 号：P159[天文地球—天文学]