Quantum Gravity Constraints from Unitarity and Analyticity
read the original abstract
We derive rigorous bounds on corrections to Einstein gravity using unitarity and analyticity of graviton scattering amplitudes. In $D\geq 4$ spacetime dimensions, these consistency conditions mandate positive coefficients for certain quartic curvature operators. We systematically enumerate all such positivity bounds in $D=4$ and $D=5$ before extending to $D\geq 6$. Afterwards, we derive positivity bounds for supersymmetric operators and verify that all of our constraints are satisfied by weakly-coupled string theories. Among quadratic curvature operators, we find that the Gauss-Bonnet term in $D\geq 5$ is inconsistent unless new degrees of freedom enter at the natural cutoff scale defined by the effective theory. Our bounds apply to perturbative ultraviolet completions of gravity.
This paper has not been read by Pith yet.
Forward citations
Cited by 10 Pith papers
-
Full positivity bounds for anomalous quartic gauge couplings in SMEFT
Complete positivity bounds for the 22 aQGC coefficients in SMEFT restrict the viable parameter space to approximately 0.0313% of the naive total.
-
Negative running of gravitational positivity
Non-minimal three-point interactions induce negative one-loop running of Wilson coefficients in gravitational EFTs, yet graviton loops generate positive IR contributions that dominate the bounds after smearing if the ...
-
Positivity with Long-Range Interactions
Defines IR-finite amplitudes M_E that preserve analyticity and unitarity to derive positivity bounds on EFTs including electromagnetism and gravity in D=4.
-
Multipositivity Constrains the Chiral Lagrangian
Multipositivity bounds derived from planar tree-level scattering amplitudes constrain Wilson coefficients of the chiral Lagrangian from below by the chiral anomaly.
-
The Equivalence Principle at High Energies Completes the Spectrum
Tree-level gravitational scattering under the equivalence principle mandates single-particle states in all irreducible representations constructible from a single seed charge, with equal interaction strengths.
-
Amplitudes and partial wave unitarity bounds
Develops spinor-helicity formalism generalizing partial wave unitarity bounds for multi-particle scattering and spin-2 or higher-spin theories.
-
Positivity in Amplitudes and Quantum Entanglement
Links amplitude positivity to S-matrix entanglement consistency for flavored states, analyzes disentanglers, and introduces wave-packet regularization for entanglement expressions.
-
Theoretical and Observational Bounds on Dynamical Chern-Simons Gravity as an Effective Field Theory
Dynamical Chern-Simons gravity is bounded by causality and perturbativity to produce only tiny corrections on macroscopic gravitational systems.
-
Higgs pair production in gluon fusion to higher orders in Higgs Effective Field Theory
Consistent NLO power counting in HEFT for di-Higgs gluon fusion requires higher-dimensional operators beyond leading order, affecting kinematic benchmarks used in experiments.
-
On Thermodynamics of Charged Black Holes, Swampland, and Dark Matter
Authors use black hole thermodynamics with dynamical cosmological constant to connect swampland conjectures and approach dark matter via scalar fields and Kaluza-Klein reduction.
discussion (0)
Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.