Massive, massless and ghost modes of gravitational waves from higher-order gravity

• Main Authors: Bogdanos, Charalampos, Capozziello, Salvatore, De Laurentis, Mariafelicia, Nesseris, Savvas
• Format: Journal Article
• Language: English
• Published: 26-01-2010
• Subjects: Physics - General Relativity and Quantum Cosmology
• DOI: 10.48550/arxiv.0911.3094

Astropart.Phys.34:236-244,2010 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), the theory contains also spin-0 and
spin-2 massive modes with the latter being, in general, ghost modes. Then, we
investigate the possible detectability of such additional polarization modes of
a stochastic gravitational wave by ground-based and space interferometric
detectors. Finally, we extend the formalism of the cross-correlation analysis,
including the additional polarization modes, and calculate the detectable
energy density of the spectrum for a stochastic background of the relic gravity
waves that corresponds to our model. For the situation considered here, we find
that these massive modes are certainly of interest for direct detection by the
LISA experiment.