Possible quantum effects at the transition from cosmological deceleration to acceleration

  title={Possible quantum effects at the transition from cosmological deceleration to acceleration},
  author={Bruno Alexandre and Jo{\~a}o Magueijo},
  journal={Physical Review D},
The recent transition from decelerated to accelerated expansion can be seen as a reflection (or “bounce”) in the connection variable, defined by the inverse comoving Hubble length ( b = ˙ a , on-shell). We study the quantum cosmology of this process. We use a formalism for obtaining relational time variables either through the demotion of the constants of Nature to integration constants, or by identifying fluid constants of motion. We extend its previous application to a toy model (radiation and… 

The Universe that came out of the wall

We re-examine the Hartle-Hawking wave function from the point of view of a quantum theory which starts from the connection representation and allows for off-shell non-constancy of Λ (as in unimodular

Quantum analysis of the recent cosmological bounce in the comoving Hubble length


The Hubble constant tension: current status and future perspectives through new cosmological probes

Maria Dainotti,a,b,c,∗ Biagio De Simone, Giovanni Montani, f ,g Tiziano Schiavone and Gaetano Lambiase National Astronomical Observatory of Japan, 2 Chome-21-1 Osawa, Mitaka, Tokyo 181-8588, Japan



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