Conveners
Gravity - Dark Energy
- Shinji Mukohyama
Standard cosmological equations are written for the Hubble volume, while the real boundary of space-time is the event horizon. Within the thermodynamic approach to gravity, the dark energy term in cosmological equations appears as an integration constant, which we fix at the event horizon and obtain the observed value for the cosmological constant.
The EDGES experiment has observed an excess trough in the brightness temperature of the 21cm absorption line of neutral Hydrogen atom (HI) from the era of cosmic dawn. We consider possible interaction of Dark Matter and Dark Energy fluid along with the cooling off of the baryon matter by its collision with Dark Matter to explain the EDGES like excess absorption feature of the 21cm signal. We...
State-of-the-art observations tightly constrain the properties of Dark Energy on Cosmological scales, where its behaviour is very close to the one of a cosmological constant. Whilst several Dark Energy candidates are capable of mimicking such a behaviour within the experiments' precision, they may be very distinguishable on smaller astrophysical scales. A rather common feature is that they...
The nonextremal Kerr black holes have been considered to be holographically dual to two- dimensional (2D) conformal field theories (CFTs). In this talk, we present the holography for the asymptotically anti-de Sitter (AdS) rotating charged black holes in extended theories of gravity. We find that the scalar wave radial equation at the near-horizon region implies the existence of the 2D...
In this paper, we have shown the matter bounce scenario of the Universe in an extended symmetric teleparallel gravity, the $f(Q)$ gravity. Motivated by the bouncing scenario and loop quantum cosmology (LQC), the form of the function $f(Q)$ has been obtained at the backdrop of Friedmann-Lema$\hat{i}$tre-Robertson Walker (FLRW) space-time. Considering the background cosmology dominated by dust...
