Conformal/Poincaré Coset, Cosmology, and Descendants of Lovelock Terms

Abstract

We calculate six invariant terms of a gravitational field theory that nonlinearly realizes the Conformal/Poincaré quotient, and reduce to the known conformal Galileons in the limit when only the conformal mode is kept. Five of the six terms are regular coset terms, while the sixth is a Wess-Zumino (WZ) term that gives the well-known gravitational action for the trace anomaly. The obtained terms can be embedded in a quantum effective field theory (EFT) without spoiling their key features, although at a cost of certain fine tunings. The additional massive modes that appear in the EFT would have been troublesome, however, for sub-Planckian curvatures their masses are (super)-Planckian and therefore the respective states are outside of the EFT regime. We discuss certain novel cosmological solution of this theory and their validity within the EFT. Furthermore, we show that the obtained 4D terms, except the WZ term, can also be derived from higher dimensional Lovelock terms by reducing the latter to the genuinely four dimensional terms according to a well-defined algorithm.

20 pages; v2: references added; published in PRD

References in corpus (15)

• Resummation of Massive Gravity
• Causality, Analyticity and an IR Obstruction to UV Completion
• Massive Gravity in Three Dimensions
• Galilean Genesis: an alternative to inflation
• A new cubic theory of gravity in five dimensions: Black hole, Birkhoff's theorem and C-function
• Is there a novel Einstein-Gauss-Bonnet theory in four dimensions?
• Derivation of Regularized Field Equations for the Einstein-Gauss-Bonnet Theory in Four Dimensions
• Galileons as Wess-Zumino Terms
• Subluminal Galilean Genesis
• Amplitudes and 4D Gauss-Bonnet Theory
• (Re-)Inventing the Relativistic Wheel: Gravity, Cosets, and Spinning Objects
• Inflation from Minkowski Space
• Nonlinear realizations of symmetries and unphysical Goldstone bosons
• Relativistic stars in a cubic Galileon Universe
• Three Dimensional Modified Gravities as Holographic Limits of Lancsoz-Lovelock Theories

Cited by in corpus (6)

• The 4D Einstein-Gauss-Bonnet Theory of Gravity: A Review
• Amplitudes and 4D Gauss-Bonnet Theory
• Higher-curvature Gravities from Braneworlds and the Holographic c-theorem
• A New Gravitational Action For The Trace Anomaly
• Black holes in a new gravitational theory with trace anomalies
• Inflation with the Trace Anomaly Action and Primordial Black Holes