225 citations · 1.8k across the 31 of their papers we have counts for
20 papers · 1 filter
The Cosmological Tree Theorem
Santiago Agui-Salcedo, Scott Melville
A number of diagrammatic "cutting rules" have recently been developed for the wavefunction of the Universe which determines cosmological correlation functions. These leverage pertu…
Orbital Precession and Hidden Symmetries in Scalar-Tensor Theories
Anne-Christine Davis, Scott Melville
We revisit the connection between relativistic orbital precession, the Laplace-Runge-Lenz symmetry, and the -channel discontinuity of scattering amplitudes. Applying this to sca…
The Analytic Wavefunction
Santiago Agui Salcedo, Mang Hei Gordon Lee, Scott Melville +1
The wavefunction in quantum field theory is an invaluable tool for tackling a variety of problems, including probing the interior of Minkowski spacetime and modelling boundary obse…
Positivity bounds from multiple vacua and their cosmological consequences
Scott Melville, Johannes Noller
Positivity bounds - constraints on any low-energy effective field theory imposed by the fundamental axioms of unitarity, causality and locality in the UV - have recently been used…
Natural Selection Rules: New Positivity Bounds for Massive Spinning Particles
Joe Davighi, Scott Melville, Tevong You
We derive new effective field theory (EFT) positivity bounds on the elastic scattering amplitudes of massive spinning particles from the standard UV properties of unitarity…
Cosmological Cutting Rules
Scott Melville, Enrico Pajer
Primordial perturbations in our universe are believed to have a quantum origin, and can be described by the wavefunction of the universe (or equivalently, cosmological correlators)…
Positivity Bounds without Boosts
Tanguy Grall, Scott Melville
We derive the first positivity bounds for low-energy Effective Field Theories (EFTs) that are not invariant under Lorentz boosts. "Positivity bounds" are the low-energy manifestati…
Quantum Corrections to Generic Branes: DBI, NLSM, and More
Garrett Goon, Scott Melville, Johannes Noller
We study quantum corrections to hypersurfaces of dimension embedded in generic higher-dimensional spacetimes. Manifest covariance is maintained throughout the analysis and…
On the time evolution of cosmological correlators
Sebastian Cespedes, Anne-Christine Davis, Scott Melville
Developing our understanding of how correlations evolve during inflation is crucial if we are to extract information about the early Universe from our late-time observables. To tha…
UV Constraints on Massive Spinning Particles: Lessons from the Gravitino
Scott Melville, Diederik Roest, David Stefanyszyn
Self-interacting massive particles with spin unavoidably violate unitarity; the question is at what scale. For spin- the strong coupling scale (at which perturbative un…
Gravitational Rainbows: LIGO and Dark Energy at its Cutoff
Claudia de Rham, Scott Melville
The recent direct detection of a neutron star merger with optical counterpart has been used to severely constrain models of dark energy that typically predict a modification of the…
Positivity Bounds for Massive Spin-1 and Spin-2 Fields
Claudia de Rham, Scott Melville, Andrew J. Tolley +1
We apply the recently developed positivity bounds for particles with spin, applied away from the forward limit, to the low energy effective theories of massive spin-1 and spin-2 th…
Improved Positivity Bounds and Massive Gravity
Claudia de Rham, Scott Melville, Andrew J. Tolley
Theories such as massive Galileons and massive gravity can satisfy the presently known improved positivity bounds provided they are weakly coupled. We discuss the form of the EFT L…
UV complete me: Positivity Bounds for Particles with Spin
Claudia de Rham, Scott Melville, Andrew J. Tolley +1
For a low energy effective theory to admit a standard local, unitary, analytic and Lorentz-invariant UV completion, its scattering amplitudes must satisfy certain inequalities. Whi…
Unitary null energy condition violation in cosmologies
Claudia de Rham, Scott Melville
A non-singular cosmological bounce in the Einstein frame can only take place if the Null Energy Condition (NEC) is violated. We explore situations where a single scalar field drive…
Massive Galileon Positivity Bounds
Claudia de Rham, Scott Melville, Andrew J. Tolley +1
The EFT coefficients in any gapped, scalar, Lorentz invariant field theory must satisfy positivity requirements if there is to exist a local, analytic Wilsonian UV completion. We a…
Positivity Bounds for Scalar Theories
Claudia de Rham, Scott Melville, Andrew J. Tolley +1
Assuming the existence of a local, analytic, unitary UV completion in a Poincaré invariant scalar field theory with a mass gap, we derive an infinite number of positivity requireme…
Generalised matter couplings in massive bigravity
Scott Melville, Johannes Noller
We investigate matter couplings in massive bigravity. We find a new family of such consistent couplings, including and extending known consistent matter couplings, and we investiga…
The coupling to matter in Massive, Bi- and Multi-Gravity
Johannes Noller, Scott Melville
In this paper we construct a family of ways in which matter can couple to one or more `metrics'/spin-2 fields in the vielbein formulation. We do so subject to requiring the weak eq…
Wilson line approach to gravity in the high energy limit
S. Melville, S. G. Naculich, H. J. Schnitzer +1
We examine the high energy (Regge) limit of gravitational scattering using a Wilson line approach previously used in the context of non-Abelian gauge theories. Our aim is to clarif…