A Reduction Algorithm for Cosmological Correlators: Cuts, Contractions, and Complexity

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Grimm, Thomas W., Hoefnagels, Arno, van Vliet, Mick
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866909531528757248
author Grimm, Thomas W.
Hoefnagels, Arno
van Vliet, Mick
author_facet Grimm, Thomas W.
Hoefnagels, Arno
van Vliet, Mick
contents Cosmological correlators are fundamental observables in an expanding universe and are highly non-trivial functions even at tree-level. In this work, we uncover novel structures in the space of such tree-level correlators that enable us to develop a new recursive algorithm for their explicit computation. We begin by formulating cosmological correlators as solutions to GKZ systems and develop a general strategy to construct additional differential operators, called reduction operators, when a GKZ system is reducible. Applying this framework, we determine all relevant reduction operators, and show that they can be used to build up the space of functions needed to represent the correlators. Beyond relating different integrals, these operators also yield a large number of algebraic relations, including cut and contraction relations between diagrams. This implies a significant reduction in the number of functions needed to represent each tree-level cosmological correlator. We present first steps to quantify the complexity of our reduction algorithm by using the Pfaffian framework. While we focus on tree-level cosmological correlators, our approach provides a blueprint for other perturbative settings.
format Preprint
id arxiv_https___arxiv_org_abs_2503_05866
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle A Reduction Algorithm for Cosmological Correlators: Cuts, Contractions, and Complexity
Grimm, Thomas W.
Hoefnagels, Arno
van Vliet, Mick
High Energy Physics - Theory
General Relativity and Quantum Cosmology
Cosmological correlators are fundamental observables in an expanding universe and are highly non-trivial functions even at tree-level. In this work, we uncover novel structures in the space of such tree-level correlators that enable us to develop a new recursive algorithm for their explicit computation. We begin by formulating cosmological correlators as solutions to GKZ systems and develop a general strategy to construct additional differential operators, called reduction operators, when a GKZ system is reducible. Applying this framework, we determine all relevant reduction operators, and show that they can be used to build up the space of functions needed to represent the correlators. Beyond relating different integrals, these operators also yield a large number of algebraic relations, including cut and contraction relations between diagrams. This implies a significant reduction in the number of functions needed to represent each tree-level cosmological correlator. We present first steps to quantify the complexity of our reduction algorithm by using the Pfaffian framework. While we focus on tree-level cosmological correlators, our approach provides a blueprint for other perturbative settings.
title A Reduction Algorithm for Cosmological Correlators: Cuts, Contractions, and Complexity
topic High Energy Physics - Theory
General Relativity and Quantum Cosmology
url https://arxiv.org/abs/2503.05866