# Polarized backgrounds of relic gravitons

@article{Giovannini2019PolarizedBO,
title={Polarized backgrounds of relic gravitons},
author={Massimo Giovannini},
journal={Physical Review D},
year={2019}
}
The polarizations of the tensor modes of the geometry evolving in cosmological backgrounds are treated as the components of a bispinor whose dynamics follows from an appropriate gauge-invariant action. This novel framework bears a close analogy with the (optical) Jones calculus and leads to a compact classification of the various interactions able to polarize the relic gravitons.
3 Citations

### Effective energy density of relic gravitons

The energy density, the pressure and the anisotropic stress of the relic gravitons do not have a unique gauge-invariant and frame-invariant expression since the equivalence principle ultimately

### Flat spectra of cosmic gravitons in the nHz and audio bands

• M. Giovannini
• Physics
Journal of Cosmology and Astroparticle Physics
• 2022
The spectra of the relic gravitons are customarily normalized in the low-frequency domain where the signal of the concordance paradigm is expected to peak and this is why their contribution to the

## References

SHOWING 1-10 OF 30 REFERENCES

### Spectra of relic gravitons and the early history of the Hubble parameter.

• Physics
Physical review. D, Particles and fields
• 1991
It is shown how one can reconstruct the time dependence of the very early Hubble parameter and matter energy density from a measured frequency-dependent spectrum of relic gravitational waves.

### Effective field theory for inflation

The methods of effective field theory are used to study generic theories of inflation with a single inflaton field. For scalar modes, the leading corrections to the R correlation function are found

### String theoretic axion coupling and the evolution of cosmic structures

• Physics
• 2000
We examine the effects of the axion coupling to RRon the evolution of cosmic structures. It is shown that the evolutions of the scalar- and vector-type perturbations are not affected by this axion

### Graviton Creation by Small Scale Factor Oscillations in an Expanding Universe

• Physics
• 2016
We treat quantum creation of gravitons by small scale factor oscillations around the average of an expanding universe. Such oscillations are predicted both by modied gravity theories with a term

### Quantum Fields in Curved Space

• Physics
• 1980
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

### Quantized Gravitational Wave Perturbations in Robertson-Walker Universes

• Physics
• 1977
We consider the theory of quantized gravitational wave perturbations in the three types of Robertson-Walker universes. In a gauge analogous to the Coulomb gauge in electrodynamics it is possible to

### Chern-Simons modification of general relativity

• Physics
• 2003
General relativity is extended by promoting the three-dimensional gravitational Chern-Simons term to four dimensions. This entails choosing an embedding coordinate v_\mu -- an external quantity,

### Cosmological signature of new parity violating interactions

• Physics
• 1999
Are there any manifestations of parity violation other than those observed in weak interactions? A map of the cosmic microwave background (CMB) temperature and polarization will provide a new

### Post-inflationary thermal histories and the refractive index of relic gravitons

We investigate the impact of the post-inflationary thermal histories on the cosmic graviton spectrum caused by the inflationary variation of their refractive index. Depending on the frequency band,