New shape for cross-bispectra in Chern-Simons gravity
Abstract Chern-Simons gravity is known to suffer from graviton ghost production during inflation, which suppresses the parity-violating power spectrum at scales relevant to cosmic microwave background observations. In this work, we show that allowing the initial conditions of inflation to deviate from the standard Bunch-Davies state can enhance parity-violating non-Gaussianity in the scalar-tensor cross-bispectra. Our results reveal a significant additional contribution to the cross-bispectra in the flattened configuration, offering a new avenue to constrain parity-violating gravity.
Authors
- Maria Mylova (ORCID: https://orcid.org/0000-0003-1772-7014)
- Perseas Christodoulidis (ORCID: https://orcid.org/0000-0003-0223-0064)
- Jinn-Ouk Gong
- Misao Sasaki
- Wei‐Chen Lin (ORCID: https://orcid.org/0000-0001-9233-4494)
Institutions
- Korea Institute for Advanced Study (KR)
- Ewha Womans University (KR)
- Kavli Institute for the Physics and Mathematics of the Universe (JP)
- National Taiwan University (TW)
- Perimeter Institute (CA)
- Kyoto University (JP)
- Asia Pacific Center for Theoretical Physics (KR)
- Pusan National University (KR)
- The University of Tokyo (JP)
Publication Details
- Journal
- Journal of Cosmology and Astroparticle Physics
- Published
- 2025-01-01
- DOI
- https://doi.org/10.1088/1475-7516/2025/01/037
- Citations
- 3
- Primary Topic
- Cosmology and Gravitation Theories
- Type
- article
- Field-Weighted Citation Impact
- 3.46