arXiv subjects

Dominik Haslehner

Publications and source records attributed to Dominik Haslehner.

3 recordsLinked to original sources

arXiv2026

Discontinuity at the Pole

The exchange of a particle whose mass is taken to zero need not reproduce the exchange of a particle that is strictly massless from the outset. We derive a general on-shell diagnostic of the well-known discontinuity between the exchange of a massless particle and the massless limit of a massive-particle exchange, valid for a mediator of arbitrary integer spin S. Our main observation is that this discontinuity can be identified directly at the level of the pole residue. We find that, in four dimensions, the residue is governed by a Chebyshev polynomial in the massless case and by a Legendre polynomial in the massless limit of the massive case. For S = 2, this reproduces the van Dam-Veltman-Zakharov discontinuity. For general S, it provides a simple and compact higher-spin analogue from on-shell factorisation. The discontinuity is probed, in principle, by the leading post-Newtonian correction to the non-relativistic potential between two massive scalar bodies.

hep-th↗

arXiv2025

Renormalising the Field-Space Geometry

We present a systematic study of one-loop quantum corrections in scalar effective field theories from a geometric viewpoint, emphasizing the role of field-space curvature and its renormalisation. By treating the scalar fields as coordinates on a Riemannian manifold, we exploit field redefinition invariance to maintain manifest coordinate independence of physical observables. Focusing on the non-linear sigma model (NLSM) and $ϕ^4$ theory, we demonstrate how loop corrections induce momentum- and scale-dependent shifts in the curvature of the field-space manifold. These corrections can be elegantly captured through the recently proposed geometry-kinematics duality, which generalizes the colour-kinematics duality in gauge theories to curved field-space backgrounds. Our results highlight a universal structure emerging in the contractions of Riemann tensors that contribute to renormalisation of the field-space curvature. In particular, we find explicit expressions and a universal structure for the running curvature and Ricci scalar in simple models, illustrating how quantum effects reshape the underlying geometry. This geometric formulation unifies a broad class of scalar EFTs, providing insight into the interplay of curvature, scattering amplitudes, and renormalisation.

hep-th↗

arXiv2021

RG of GR from On-shell Amplitudes

We study the renormalization group of generic effective field theories that include gravity. We follow the on-shell amplitude approach, which provides a simple and efficient method to extract anomalous dimensions avoiding complications from gauge redundancies. As an invaluable tool we introduce a modified helicity $\tilde{h}$ under which gravitons carry one unit instead of two. With this modified helicity we easily explain old and uncover new non-renormalization theorems for theories including gravitons. We provide complete results for the one-loop gravitational renormalization of a generic minimally coupled gauge theory with scalars and fermions and all orders in $M_{Pl}$, as well as for the renormalization of dimension-six operators including at least one graviton, all up to four external particles.

hep-th↗