scholarly journals Parity breaking signatures from a Chern-Simons coupling during inflation: the case of non-Gaussian gravitational waves

2017 ◽  
Vol 2017 (07) ◽  
pp. 034-034 ◽  
Author(s):  
Nicola Bartolo ◽  
Giorgio Orlando
Keyword(s):  
Gravitational Waves ◽  
Non Gaussian ◽  
Chern Simons ◽  
Parity Breaking

scholarly journals Inflationary birefringence and baryogenesis

2016 ◽  
Vol 25 (11) ◽  
pp. 1640013 ◽  
Author(s):  
Stephon Alexander
Keyword(s):  
Gravitational Waves ◽  
Lepton Number ◽  
Gauge Fields ◽  
Lepton Asymmetry ◽  
Complex Phase ◽  
Inflaton Field ◽  
Model Based ◽  
Cross Correlations ◽  
Chern Simons

A decade ago, the first leptogenesis model based on inflation was proposed, where the complex phase of the inflaton field carries lepton number [S. H. S. Alexander, M. E. Peskin and M. M. Sheikh-Jabbari, Phys. Rev. Lett. 96 (2006) 081301, arXiv:hep-th/0403069 ]. If the inflaton field is an axion, it can couple to gravitational waves and gauge fields via Chern–Simons invariants. Due to these couplings, birefringent gravitational and gauge primordial perturbations are created during inflation to generate a lepton asymmetry, establishing a possible connection between nonvanishing TB-parity-violating polarization cross-correlations and leptogenesis. We also discuss the prospect for a subset of these models which can directly source circular (V-mode) polarization in the CMB.

scholarly journals The holographic spacetime model of cosmology

2018 ◽  
Vol 27 (14) ◽  
pp. 1846005 ◽  
Author(s):  
Tom Banks ◽  
W. Fischler
Keyword(s):  
Dark Matter ◽  
Gravitational Waves ◽  
Structure Formation ◽  
Big Bang ◽  
Baryon Asymmetry ◽  
Gaussian Fluctuations ◽  
Primordial Gravitational Waves ◽  
Conventional Models ◽  
Non Gaussian ◽  
The Big Bang

This essay outlines the Holographic Spacetime (HST) theory of cosmology and its relation to conventional theories of inflation. The predictions of the theory are compatible with observations, and one must hope for data on primordial gravitational waves or non-Gaussian fluctuations to distinguish it from conventional models. The model predicts an early era of structure formation, prior to the Big Bang. Understanding the fate of those structures requires complicated simulations that have not yet been done. The result of those calculations might falsify the model, or might provide a very economical framework for explaining dark matter and the generation of the baryon asymmetry.

scholarly journals Measuring chiral gravitational waves in Chern-Simons gravity with CMB bispectra

2019 ◽  
Vol 2019 (01) ◽  
pp. 050-050 ◽  
Author(s):  
Nicola Bartolo ◽  
Giorgio Orlando ◽  
Maresuke Shiraishi
Keyword(s):  
Gravitational Waves ◽  
Chern Simons

scholarly journals Robust statistics for deterministic and stochastic gravitational waves in non-Gaussian noise: Frequentist analyses

2002 ◽  
Vol 65 (12) ◽  
Author(s):  
Bruce Allen ◽  
Jolien D. E. Creighton ◽  
Éanna É. Flanagan ◽  
Joseph D. Romano
Keyword(s):  
Gravitational Waves ◽  
Gaussian Noise ◽  
Robust Statistics ◽  
Non Gaussian

scholarly journals Gravitational waves propagation in nondynamical Chern–Simons gravity

2017 ◽  
Vol 26 (13) ◽  
pp. 1750148
Author(s):  
A. Martín-Ruiz ◽  
L. F. Urrutia
Keyword(s):  
Surface Layer ◽  
Domain Wall ◽  
Gravitational Waves ◽  
Electromagnetic Waves ◽  
Condensed Matter ◽  
Additional Contribution ◽  
Reflection And Transmission ◽  
First Derivative ◽  
Waves Propagation ◽  
Chern Simons

We investigate the propagation of gravitational waves in linearized Chern–Simons (CS) modified gravity by considering two nondynamical models for the coupling field [Formula: see text]: (i) a domain wall and (ii) a surface layer of [Formula: see text], motivated by their relevance in condensed matter physics. We demonstrate that the metric and its first derivative become discontinuous for a domain wall of [Formula: see text], and we determine the boundary conditions by realizing that the additional contribution to the wave equation corresponds to one of the self-adjoint extensions of the D'Alembert operator. Nevertheless, such discontinuous metric satisfies the area matching conditions introduced by Barrett. On the other hand, the propagation through a surface layer of [Formula: see text] behaves similarly to the propagation of electromagnetic waves in CS extended electrodynamics. In both cases, we calculate the corresponding reflection and transmission amplitudes. As a consequence of the distributional character of the additional terms in the equations that describe wave propagation, the results obtained for the domain wall are not reproduced when the thickness of the surface layer goes to zero, as one could naively expect.

scholarly journals Propagation of gravitational waves in Chern-Simons axion Einstein gravity

2019 ◽  
Vol 100 (8) ◽  
Author(s):  
Shin’ichi Nojiri ◽  
S. D. Odintsov ◽  
V. K. Oikonomou ◽  
Arkady A. Popov
Keyword(s):  
Gravitational Waves ◽  
Einstein Gravity ◽  
Chern Simons
Sign in / Sign up

Export Citation Format

Share Document