4 papers
Covariant extrinsic curvature expansion of the nonlocal effective action for a massless scalar field on a manifold with boundary
A. Boasso, C. D. Fosco, B. C. Guntsche +1
We study the nonlocal effective action of a massless scalar field defined on a flat manifold with a curved boundary. Using a heat-kernel approach, we derive a covariant expansion o…
Nonlocal stress-energy tensor in time-dependent gravitational backgrounds
A. Boasso, F. D. Mazzitelli
We analyze the renormalized stress-energy tensor (RSET) of a massless quantum scalar field in time-dependent gravitational backgrounds. Starting from its formal expression obtained…
Vacuum polarization in the horizonless Bardeen metric
Andrés Boasso, Francisco D. Mazzitelli
We compute the renormalized stress-energy tensor for a massless quantum scalar field in the background of the horizonless Bardeen spacetime. Within the weak-field approximation, we…
Nonlocal effective action and particle creation in dimensions
Andrés Boasso, Sebastián Franchino-Viñas, Francisco D. Mazzitelli
We compute the particle creation rate in the context of quantum fields in curved spacetimes, by evaluating the imaginary part of the effective action up to second order in the curv…