30 research outputs found
Scalar QNMs for higher dimensional black holes surrounded by quintessence in Rastall gravity
The spacetime solution for a black hole, surrounded by an exotic matter
field, in Rastall gravity, is calculated in an arbitrary d-dimensional
spacetime. After this, we calculate the scalar quasinormal modes of such
solution, and study the shift on the modes caused by the modification of the
theory of gravity, i.e., by the introduction of a new term due to Rastall. We
conclude that the shift strongly depends on the kind of exotic field one is
studying, but for a low density matter that supposedly pervades the universe,
it is unlikely that Rastall gravity will cause any instability on the probe
field.Comment: 6 figures, 11 page
Rainbows without unicorns: Metric structures in theories with Modified Dispersion Relations
Rainbow metrics are a widely used approach to metric formalism for theories
with Modified Dispersion Relations. They have had a huge success in the Quantum
Gravity Phenomenology literature, since they allow to introduce
momentum-dependent spacetime metrics into the description of systems with
Modified Dispersion Relation. In this paper, we introduce the reader to some
realizations of this general idea: the original Rainbow metrics proposal, the
momentum-space-inspired metric, the standard Finsler geometry approach and our
alternative definition of a four-velocity-dependent metric with a massless
limit. This paper aims to highlight some of their properties and how to
properly describe their relativistic realizations.Comment: 10 pages. Discussion on the role of connections was added. Matches
published versio
Thermal quantum correlations in two gravitational cat states
We consider the effect of a thermal bath on quantum correlations induced by
the gravitational interaction between two massive cat states. Entanglement
(measured by the concurrence) and quantum coherence (measured by the
-norm) are analyzed from the thermal quantum density operator. We
investigate and discuss the behavior of these quantities under temperature
variations in different regimes, including some that are expected to be
experimentally feasible in the future.Comment: 8 pages, 9 figures. Added references and corrected typo
Cloud of strings in f(R) gravity
We derive the solution for a spherically symmetric string cloud configuration
in a d-dimensional spacetime in the framework of f(R) theories of gravity. We
also analyze some thermodynamic properties of the joint black hole - cloud of
strings solution. For its Hawking temperature, we found that the dependence of
the mass with the horizon is significantly different in both theories. For the
interaction of a black hole with thermal radiation, we found that the shapes of
the curves are similar, but shifted. Our analysis generalizes some known
results in the literature.Comment: Version accepted for CP
Muon accelerators -- Muon lifetime measurements as window to Planck scale physics
A prominent effective description of particles interacting with the quantum
properties of gravity is through modifications of the general relativistic
dispersion relation. Such modified dispersion relations lead to modifications
in the relativistic time dilation. A perfect probe for this effect, which goes
with the particle energy cubed over the quantum gravity scale
and the square of the particle mass would be a very light
unstable particle for which one can detect the lifetime in the laboratory as a
function of its energy to very high precision. In this article we conjecture
that a muon collider or accelerator would be a perfect tool to investigate the
existence of an anomalous time dilation, and with it the fundamental structure
of spacetime at the Planck scale.Comment: 12 pages, 2 figures. Matches version published in Classical and
Quantum Gravity Focus Issue: "Focus on Quantum Gravity Phenomenology in the
Multi-Messenger Era: Challenges and Perspectives