arXiv subjects

Brett Oertel

Publications and source records attributed to Brett Oertel.

4 recordsLinked to original sources

arXiv2026

Finite-time memory detectors and fully constraining Faddeev-Kulish dressings in QED and gravity

We show that for both QED and perturbative quantum gravity, finite-time Faddeev-Kulish dressings can be fully constrained by symmetry, and that this gives the unique choice which reproduces the classical memory effect. For gravity, we show that using this dressing to construct finite-time Fock spaces, as well as a carefully defined finite-time memory detector allows us to recover both the first order gravitational memory, as well as higher order Christodoulou contributions from the gravitational field. We explain how these higher order perturbative corrections arise in inclusive in-in calculations.

hep-th↗

arXiv2026

Asymptotic charges as detectors and the memory effect in massive QED and perturbative quantum gravity

It has been shown that there are an infinite set of asymptotic symmetries in quantum gravity and QED, and this has been extended to dressed states in some cases. Here we rederive these statements in terms of detectors in order to clarify, confirm, and generalize these results to include external hard gravitons. Using detectors and including the full t dependence in Faddeev-Kulish dressings allows us to correct discrepancies in the literature and make new statements. We show that Faddeev-Kulish dressings correctly encode the memory effect in the 'in' and 'out' scattering Fock spaces. We find a physical contribution to the memory eigenvalues arising from the dressings in both cases.

hep-th↗

arXiv2023

Missing local operators, zeros, and twist-4 trajectories

The number of local operators in a CFT below a given twist grows with spin. Consistency with analyticity in spin then requires that at low spin, infinitely many Regge trajectories must decouple from local correlation functions, implying infinitely many vanishing conditions for OPE coefficients. In this paper we explain the mechanism behind this infinity of zeros. Specifically, the mechanism is related to the two-point function rather than the three-point function, explaining the vanishing of OPE coefficients in every correlator from a single condition. We illustrate our result by studying twist-4 Regge trajectories in the Wilson--Fisher CFT at one loop.

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arXiv2021

On disc-with-hole and disc-with-handle partition functions in bosonic string theory

Higher genus partition functions of string world sheets with boundaries are relevant, e.g. for computation of quantum corrections to Wilson loop expectation values. As a preparation for a possible study of strings in curved space like AdS here we consider examples of genus one partition functions of string world-sheets ending on a circle in the bosonic string theory in flat space. We begin with the partition function for annular topology, writing it as an integral over the modulus of the annulus. In the process, we compute the determinant of the Laplacian on the annulus for Dirichlet-Dirichlet and Dirichlet-Neumann boundary conditions. We then consider the case of the disc-with-handle topology using the gluing method. We first write the partition function using a Schottky parameterisation of the moduli space and then as an integral over the period matrix.

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