The exploration of the universe has recently entered a new era thanks to the multi-
messenger paradigm, characterized by a continuous increase in the quantity and quality of …

A large number of models have been analyzed in loop quantum cosmology, using mainly
minisuperspace constructions and perturbations. At the same time, general physics …

We derive an effective dynamics for scalar cosmological perturbations from quantum gravity,
in the framework of group field theory condensate cosmology. The emergent spacetime …

We analyse the emergent cosmological dynamics corresponding to the mean field
hydrodynamics of quantum gravity condensates, in the group field theory formalism. We …

A bstract We discuss the relational strategy to solve the problem of time in quantum gravity
and different ways in which it could be implemented, pointing out in particular the …

In cosmological group field theory (GFT) models for quantum gravity coupled to a massless
scalar field the total volume, seen as a function of the scalar field, follows the classical …

We analyze the size and evolution of quantum fluctuations of cosmologically relevant
geometric observables, in the context of the effective relational cosmological dynamics of …

A bstract In the tensorial group field theory approach to quantum gravity, the theory is based
on discrete building blocks and continuum spacetime is expected to emerge from their …

We derive the dynamics of (isotropic) scalar perturbations from the mean-field
hydrodynamics of full Lorentzian quantum gravity, as described by a two-sector (timelike and …

Canonical quantization of gravitational systems is obstructed by the problem of time. Due to
diffeomorphism symmetry the Hamiltonian vanishes: dynamics with respect to a background …