Study On The Evolution And Related Properties Of Holographic Dark Energy Model With Generalized Entropy In The DGP Braneworld

The problem of accelerated expansion of the universe has been developed so far,and it is at the forefront of modern cosmology,both theoretically and experimentally.Physicists mainly explain it from two aspects:modified gravity and dark energy.The DGP braneworld model,as a modified gravity model,proposes an infinite Minkowski volume that is well suited to explain the acceleration of the late universe.Since the brane embedded volume has two different states,the DGP braneworld model consists of two independent branches,namely the self-accelerating branch and the normal branch.The self-accelerating branch appears to have no matter or energy on the brane,and it can automatically drive the late acceleration of the universe.In the case of the normal branch,a dark energy component needs to be added to the universe to realize the accelerated expansion of the late universe.In this paper,we consider a flat FRW universe filled with interacting dark energy and cold dark matter within the framework of the DGP braneworld.By assuming that the Hub-ble horizon is IR cutoff,the author studies the cosmological evolution properties and related thermodynamic problems of Tsallis holographic dark energy(THDE)and Renyi holographic dark energy(RHDE)models in the DGP braneworld.The main contents are as follows:Firstly,the cosmological evolution of holographic dark energy models with generalized entropy in the DGP braneworld is studied.The evolution laws of energy density parameters?deceleration parameters and EOS(equation of state)parameters of two kinds of holographic dark energy models with generalized entropy are researched in the case of no interaction and three different interactions.It is worth noting that the Tsallis holographic dark energy model can only pass through Phantom divide when the interaction is considered.In contrast,regardless of whether interaction is considered,the state parameters of the Renyi holographic dark energy model can slowly pass through-1 near the present value.Secondly,we will geometrically diagnose the models with the three ways of the statefinder hierarchy,Om(z)and composite null diagno-sis(CND).It can be found that these three kinds of diagnosis can distinguish the dark energy models with different interactions and coupling parameters from the ACDM model.Finally,the thermodynamic properties of two types of holographic dark energy models with generalized en-tropy under the framework of DGP braneworld are discussed in the case of interactions,and the validity of the generalized second law of thermodynamics and thermal equilibrium is verified by drawing images.