Dark energy and cosmological horizon thermal effects

We investigate various dark energy models by taking into account the thermal effects induced from Hawking radiation on the apparent horizon of the Universe, for example, near a finite-time future singularity. If the dark energy density increases as the Universe expands, the Universe's evolution reaches a type II singularity (or sudden future singularity). The second derivative of the scale factor diverges, but the first derivative remains finite. Quasi-de Sitter evolution can change to sudden future singularity in the case of with an effective cosmological constant larger than the maximum possible value of the energy density of the Universe. Another interesting feature of the cosmological solution is the possibility of a transition between deceleration and acceleration for quintessence dark energy with a simple equation of state. Finally, we investigate which fluid component can remedy big rip singularities and other crushing-type singularities.

Automated summary

By considering the thermal effects induced from Hawking radiation on the apparent horizon of the Universe, various dark energy models were investigated. The study explored the evolution of dark energy density as the Universe expands, leading to different types of singularities, such as sudden future singularities and big rip singularities. The research also looked into the transition between deceleration and acceleration in quintessence dark energy, as well as the potential remedies for crushing-type singularities.