author={Mariafelicia De Laurentis and Salvatore Capozziello and Giuseppe Basini},
  journal={Modern Physics Letters A},
We linearize the field equations for higher order theories of gravity that contain scalar invariants other than the Ricci scalar. We find that besides a massless spin-2 field (the standard graviton), the theory contains also spin-0 and spin-2 massive modes with the latter being, in general, ghost modes. The rate at which such particles would emit gravitational Cherenkov radiation is calculated for some interesting physical cases. 
Gravitoelectromagnetism, Cherenkov radiation at finite temperature
Gravitoelectromagnetism (GEM) is a gravitational theory similar to electromagnetism. The GEM Lagrangian formalism is used to consider a study of the Cherenkov radiation. This allows us to consider
Maximal acceleration and radiative processes
We derive the radiation characteristics of an accelerated, charged particle in a model due to Caianiello in which the proper acceleration of a particle of mass m has the upper limit 𝒜m = 2mc3/ℏ. We
Testing local Lorentz invariance with gravitational waves
The effects of local Lorentz violation on dispersion and birefringence of gravitational waves are investigated. The covariant dispersion relation for gravitational waves involving gauge-invariant
Tests of Lorentz Symmetry in the Gravitational Sector
Lorentz symmetry is one of the pillars of both General Relativity and the Standard Model of particle physics. Motivated by ideas about quantum gravity, unification theories and violations of CPT
Constraints on Lorentz violation from gravitational Čerenkov radiation
Limits on gravitational Cerenkov radiation by cosmic rays are obtained and used to constrain coefficients for Lorentz violation in the gravity sector associated with operators of even mass
Signals for Lorentz violation in gravitational waves
Lorentz violations in gravitational waves are investigated. Plane-wave solutions for arbitrary gauge-invariant violations in linearized gravity are constructed. Signatures of Lorentz violation


Massive, massless and ghost modes of gravitational waves from higher-order gravity
Abstract We linearize the field equations for higher order theories that contain scalar invariants other than the Ricci scalar. We find that besides a massless spin-2 field (the standard graviton),
Probing the Brans-Dicke gravitational field by Cherenkov radiation
The possibility that a charged particle propagating in a gravitational field described by Brans-Dicke theory of gravity could emit Cherenkov radiation is explored. This process is kinematically
Higher-order gravity and thecosmological background of gravitational waves"
Abstract The cosmological background of gravitational waves can be tuned by the higher-order corrections to the gravitational Lagrangian. In particular, it can be shown that assuming R 1 + ϵ , where
Cerenkov radiation emitted by charged particles in a gravitational field
Charged particles propagating in an external gravitational field with negative Ricci tensor components can emit radiation by the Cerenkov process. The external gravitational field acts like an
Ghost constraints on modified gravity
Abstract We show that general infrared modifications of the Einstein–Hilbert action obtained by addition of curvature invariants are not viable. These modifications contain either ghosts or light
Deriving the mass of particles from Extended Theories of Gravity in LHC era
We derive a geometrical approach to produce the mass of particles that could be suitably tested at LHC. Starting from a 5D unification scheme, we show that all the known interactions could be
Quadrupolar gravitational radiation as a test-bed for f(R)-gravity
Abstract The debate concerning the viability of f(R)-gravity as a natural extension of General Relativity could be realistically addressed by using results coming from binary pulsars like PSR 1913 +
Massive and mass-less Yang-Mills and gravitational fields
Massive and mass-less Yang-Mills and gravitational fields are considered. It is found that there is a discrete difference between the zero-mass theories and the very small, but non-zero mass
Quantum Fields in Curved Space
This book presents a comprehensive review of the subject of gravitational effects in quantum field theory. Although the treatment is general, special emphasis is given to the Hawking black hole
Extended Theories of Gravity
Abstract Extended Theories of Gravity can be considered as a new paradigm to cure shortcomings of General Relativity at infrared and ultraviolet scales. They are an approach that, by preserving the