Quantum Hubble horizon

The article addresses the possibility of obtaining cosmologically relevant effects from the quantum nature of the Hubble horizon. Following the observation made by Bianchi and Rovelli (Phys Rev D 84:027502, 2011) we explore the relationship between the Planck scale discreteness of the Hubble horizon and deformations of the symmetry of rotations. We show that the so-called q-deformations in a natural way lead to a mechanism of condensation in the very early Universe. We argue that this provides a possible resolution of the problem of the initial homogeneity at the onset of inflation. Furthermore, we perform an analysis in terms of entropy of the quantum Hubble horizon and show that the ΛCDM model may arise from a linearly corrected Bekenstein–Hawking entropy (that is, linearly in area of the horizon). Based on this, we show that the current accelerating expansion can be associated with the entropy decrease in the Hubble volume. The results presented open new ways to explore the relation between the Planck scale effects and observationally relevant features of our Universe.