4 papers
Reflection positivity in a higher-derivative model with physical bound states of ghosts
Manuel Asorey, Gastão Krein, Miguel Pardina +1
The inclusion of higher derivatives is a necessary condition for a renormalizable or superrenormalizable local theory of quantum gravity. On the other hand, higher derivatives lead…
Isospectrality and non-locality of generalized Dirac combs
Giuliano Angelone, Manuel Asorey, Fernando Ezquerro +1
We consider a generalization of Dirac's comb model, describing a non-relativistic particle moving in a periodic array of generalized point interactions. The latter represent the mo…
New vacuum boundary effects of massive field theories
Manuel Asorey, Fernando Ezquerro, Miguel Pardina
Analytical arguments suggest that the Casimir energy in 2+1 dimensions for gauge theories exponentially decays with the distance between the boundaries. The phenomenon has also bee…
Stability of cosmological singularity-free solutions in quadratic gravity
M. Asorey, F. Ezquerro, M. Pardina
We introduce a large family of homogeneous and isotropic cosmological solutions in quadratic gravity which are singularity-free at early and late times. This kind of smooth solutio…