Black hole superradiance is a powerful probe of light, weakly coupled hidden sector
particles. Many candidate particles, such as axions, generically have self-interactions that …

A bstract Quantum scattering amplitudes for massive matter have received new attention in
connection to classical calculations relevant to gravitational-wave physics. Amplitude …

A bstract We develop massive higher-spin theory as a framework for describing dynamics of
rotating compact objects, such as Kerr black holes. In this paper, we explore gauge …

A bstract We derive new effective field theory (EFT) positivity bounds on the elastic 2→ 2
scattering amplitudes of massive spinning particles from the standard UV properties of …

A bstract According to common lore, massive elementary higher spin particles lead to
inconsistencies when coupled to gravity. However, this scenario was not completely ruled …

A bstract In the context of perturbative quantum field theory, the addition of quadratic-
curvature invariants to the Einstein-Hilbert action makes it possible to achieve strict …

We consider effective theories with massive fields that have spins larger than or equal to
two. We conjecture a universal cutoff scale on any such theory that depends on the lightest …

A bstract We discuss recursion relations for scattering amplitudes with massive particles of
any spin. They are derived via a two-parameter shift of momenta, combining a BCFW-type …

A bstract We initiate a systematic study of the self-interactions of a massive spin-2 “graviton”
consistent with up to\(\mathcal {N}\)= 4 supersymmetry. Using a recently developed massive …

A bstract We construct the effective field theory for a single massive higher-spin particle in
flat spacetime. Positivity bounds of the S-matrix force the cutoff of the theory to be well below …