Dark Energy and Cosmological Horizon Thermal Effects

• Main Authors: Astashenok, Artyom V, Odintsov, Sergei D, Oikonomou, Vasilis K
• Format: Journal Article
• Language: English
• Published: 17-01-2021
• Subjects: Physics - General Relativity and Quantum Cosmology
• DOI: 10.48550/arxiv.2101.06657

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
singularity of II type (or sudden future singularity). The second derivative of
scale factor diverges but the first remains finite. Quasi-de Sitter evolution
can change on sudden future singularity in the case of having an effective
cosmological constant larger than the maximum possible value of the energy
density of the Universe. Another interesting feature of 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.