Universal bound on the strong coupling scale of a gravitationally coupled massive spin-2 particle

2018/06/30 by James Bonifacio, Kurt Hinterbichler
Mathematics · Physics and Astronomy · #Amplitude #Black Holes and Theoretical Physics #Classical mechanics #Cosmology and Gravitation Theories #Coupling (piping) #Curvature #Degrees of freedom (physics and chemistry) #Geometry #Gravitation #Graviton #Massive gravity #Mathematical physics #Mathematics #Noncommutative and Quantum Gravity Theories #Physics #Quantum mechanics #Scale (ratio) #Scattering amplitude #Spin (aerodynamics) #Unitarity #hep-th

paper · pdf · doi:10.1103/physrevd.98.085006

published as Phys. Rev. D 98, 085006 (2018) · 28 pages. v2 refs added

arxiv created 2018/08/08 · openalex publication_date 2018/10/08 · arxiv updated 2018/10/17 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05

Abstract

We find a model-independent upper bound on the strong coupling scale for a massive spin-2 particle coupled to Einstein gravity. Our approach is to directly construct tree-level scattering amplitudes for these degrees of freedom and use them to find the maximum scale of perturbative unitarity violation. The highest scale is \mathrm\ensuremathΛ₃=(m²M_P)^1/3, which is saturated by ghost-free bigravity. The strong coupling scale can be further raised to M_P if the kinetic term for one particle has the wrong sign, which uniquely gives the amplitudes of quadratic curvature gravity. We also discuss the generalization to massive higher-spin particles coupled to gravity.

Citations

• Electromagnetically Interacting Massive Spin-2 Field: Intrinsic Cutoff and Pathologies in External Fields
• Consistency Conditions on the S-Matrix of Massless Particles
• Scattering amplitudes in super-renormalizable gravity
• On gravitational interactions for massive higher spins in AdS3
• Intrinsic cutoff and acausality for massive spin 2 fields coupled to electromagnetism
• Theoretical Aspects of Massive Gravity
• Note on massive spin 2 in curved space
• Bimetric gravity from ghost-free massive gravity
• Resummation of Massive Gravity
• Tree-level unitarity constraints on the gravitational couplings of higher-spin massive fields
• Comments on Higher-Spin Fields in Nontrivial Backgrounds
• UV complete me: positivity bounds for particles with spin
• Scattering Amplitudes For All Masses and Spins
• Massive Gravity