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20192025
most citedExtension of positivity bounds to non-local theories: IR obstructions to Lorentz invariant UV completions

13 citations · 13 across the 2 of their papers we have counts for

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hep-th2025

False and genuine decoherence in the early universe: a local observer and time-averaged observables

Fumiya Sano, Junsei Tokuda

We study quantum decoherence of curvature perturbations at superhorizon scales caused by the gravitational nonlinearities. We show that cubic gravitational couplings, constrained b…

hep-th2024

String loops and gravitational positivity bounds: imprint of light particles at high energies

Simon Caron-Huot, Junsei Tokuda

We study loop corrections to positivity bounds on effective field theories in the context of scattering in gravitational theories, in the presence of light particles. It h…

hep-th2023

Stochastic tunneling in de Sitter spacetime

Taiga Miyachi, Jiro Soda, Junsei Tokuda

Tunneling processes in de Sitter spacetime are studied by using the stochastic approach. We exploit the Martin-Siggia-Rose-Janssen-de Dominicis (MSRJD) functional integral to obtai…

hep-th2023

Cancellation of quantum corrections on the soft curvature perturbations

Yuichiro Tada, Takahiro Terada, Junsei Tokuda

We study the cancellation of quantum corrections on the superhorizon curvature perturbations from subhorizon physics beyond the single-clock inflation from the viewpoint of the cos…

hep-th2023

New lower bounds on scattering amplitudes: non-locality constraints

Luca Buoninfante, Junsei Tokuda, Masahide Yamaguchi

Under reasonable working assumptions including the polynomial boundedness, one proves the well-known Cerulus-Martin lower bound on how fast an elastic scattering amplitude can decr…

hep-th2021

Gravitational Positivity Bounds on Scalar Potentials

Toshifumi Noumi, Junsei Tokuda

We derive constraints on scalar field theories coupled to gravity by using recently developed positivity bounds in the presence of gravity. It is found that a canonically-normalize…