Horndeski in the Swampland

Abstract

We investigate the implications of string Swampland criteria for alternative theories of gravity. Even though this has not rigorously been proven, there is some evidence that exact de-Sitter solutions with a positive cosmological constant cannot be successfully embedded into string theory, and that the low energy effective field theories containing a scalar field $\pi$ with a potential $V$ in the habitable landscape should satisfy the Swampland criteria $|V^{\prime }|/V\ge c\sim \mathcal{O}(1)$. As a paradigmatic class of modified gravity theories for inflation and dark energy, we consider the extensively studied family of Horndeski Lagrangians in view of cosmological observations. Apart from a possible potential term, they contain derivative self-interactions as the Galileon and non-minimal couplings to the gravity sector. Hence, our conclusions on the Galileon sector can be also applied to many other alternative theories with scalar helicity modes containing derivative interactions such as massive gravity and generalized Proca. In the presence of such derivative terms, the dynamics of the scalar mode is substantially modified, and imposing the cosmological evolution constrained by observations places tight constraints on $c$ within the Swampland conjecture.

arXiv comment8 pages, 5 figues, published version

References in corpus (41)

• The Complete Light-curve Sample of Spectroscopically Confirmed Type Ia Supernovae from Pan-STARRS1 and Cosmological Constraints from The Combined Pantheon Sample
• Exploring the Expansion History of the Universe
• Accelerating Universes with Scaling Dark Matter
• The galileon as a local modification of gravity
• Resummation of Massive Gravity
• On the Geometry of the String Landscape and the Swampland
• Generalized G-inflation: Inflation with the most general second-order field equations
• From k-essence to generalised Galileons
• Covariant Galileon
• Dark Energy after GW170817: dead ends and the road ahead
• Cosmology and fundamental physics with the Euclid satellite
• Strong constraints on cosmological gravity from GW170817 and GRB 170817A
• Dark Energy after GW170817 and GRB170817A
• Distance and de Sitter Conjectures on the Swampland
• Implications of the Neutron Star Merger GW170817 for Cosmological Scalar-Tensor Theories
• Generalized Galileons: All scalar models whose curved background extensions maintain second-order field equations and stress tensors
• Imperfect Dark Energy from Kinetic Gravity Braiding
• On the Cosmological Implications of the String Swampland
• Generalization of the Proca Action
• A systematic approach to generalisations of General Relativity and their cosmological implications
• What if string theory has no de Sitter vacua?
• Cosmic Acceleration from Abelian Symmetry Breaking
• Derivative self-interactions for a massive vector field
• Dark energy in Horndeski theories after GW170817: A review
• On the de Sitter swampland criterion
• Cosmology of the Galileon from Massive Gravity
• Dark Energy in light of Multi-Messenger Gravitational-Wave astronomy
• Generalized Proca action for an Abelian vector field
• The dS swampland conjecture and the Higgs potential
• Dark Energy in the Swampland
• Beyond generalized Proca theories
• The zoo plot meets the swampland: mutual (in)consistency of single-field inflation, string conjectures, and cosmological data
• Massive Galileon Positivity Bounds
• Supersymmetry Breaking by Fluxes
• Weakly Broken Galileon Symmetry
• M-theory and Type IIA Flux Compactifications
• Quintessence Saves Higgs Instability
• A de Sitter Farey Tail
• Phenomenological Consequences of the Refined Swampland Conjecture
• Small-Field and Scale-Free: Inflation and Ekpyrosis at their Extremes
• Cosmology with a successful Vainshtein screening in theories beyond Horndeski

Cited by in corpus (20)

• Swampland conjecture in $f(R)$ gravity by the Noether Symmetry Approach
• Quantum aspects of chaos and complexity from bouncing cosmology: A study with two-mode single field squeezed state formalism
• A hint of matter underdensity at low $z$?
• Hyperbolic field space and swampland conjecture for DBI scalar
• Multi-field Inflation in High-Slope Potentials
• Relating the scalar weak gravity conjecture and the swampland distance conjecture for an accelerating universe
• Eternal Inflation, Entropy Bounds and the Swampland
• Swampland Criteria in the Slotheon Field Dark Energy
• Constraints on dark energy models from the Horndeski theory
• Stability, dark energy parameterization and swampland aspect of Bianchi Type-$V{I}_h$ cosmological models with f(R, T)-gravity
• Non-canonical kinetic structures in the swampland
• Scalar-Connection Gravity and Spontaneous Scalarization
• Axion Monodromy Inflation, Trapping Mechanisms and the Swampland
• Refined Swampland conjecture in deformed Starobinsky gravity
• The Stringy Origins of Galileons and their Novel Limit
• Exponential quintessence with momentum coupling to dark matter
• How Much NEC Breaking Can the Universe Endure?
• Hitchhiker's Guide to the Swampland: The Cosmologist's Handbook to the string-theoretical Swampland Programme
• Lanczos equation on light-like hypersurfaces in a cosmologically viable class of kinetic gravity braiding theories
• Cosmic acceleration from string induced Galileons