Conformal Killing tensors and their Killing scales

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Gover, A. Rod, Kress, Jonathan, Leistner, Thomas
Format: Preprint
Published: 2024
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866929399055515648
author Gover, A. Rod
Kress, Jonathan
Leistner, Thomas
author_facet Gover, A. Rod
Kress, Jonathan
Leistner, Thomas
contents We address the problem of how to characterise when a rank-two conformal Killing tensor is the trace-free part of a Killing tensor for a metric in the conformal class. We call such a metric a Killing scale. Our approach is via differential prolongation using conformally invariant tractor calculus. First, we show that there is a useful partial prolongation of the conformal Killing equation to a simplified equation for sections of some tractor bundle. We then use this partial prolongation to provide such an invariant characterisation in terms of the scale tractor and this partial prolongation. This captures invariantly the relevant Bertrand--Darboux equation. We show that Einstein Killing scales have a special place in the theory. On conformally flat manifolds, we give the full prolongation of the conformally Killing equation to a conformally invariant connection on a tractor bundle. Using this, we provide a characterisation of (non-scalar flat) Einstein Killing scales by an algebraic equation for the scale tractors corresponding to such metrics. This also provides an algebraic description of the linear subspace of conformal Killing tensors that are compatible with a given Einstein Killing scale. For completeness and to introduce the main ideas, we also study analogous questions for conformal Killing vectors.
format Preprint
id arxiv_https___arxiv_org_abs_2406_17212
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Conformal Killing tensors and their Killing scales
Gover, A. Rod
Kress, Jonathan
Leistner, Thomas
Differential Geometry
53A30, 53C18, 53A20, 53B15, 70H33, 37K10
We address the problem of how to characterise when a rank-two conformal Killing tensor is the trace-free part of a Killing tensor for a metric in the conformal class. We call such a metric a Killing scale. Our approach is via differential prolongation using conformally invariant tractor calculus. First, we show that there is a useful partial prolongation of the conformal Killing equation to a simplified equation for sections of some tractor bundle. We then use this partial prolongation to provide such an invariant characterisation in terms of the scale tractor and this partial prolongation. This captures invariantly the relevant Bertrand--Darboux equation. We show that Einstein Killing scales have a special place in the theory. On conformally flat manifolds, we give the full prolongation of the conformally Killing equation to a conformally invariant connection on a tractor bundle. Using this, we provide a characterisation of (non-scalar flat) Einstein Killing scales by an algebraic equation for the scale tractors corresponding to such metrics. This also provides an algebraic description of the linear subspace of conformal Killing tensors that are compatible with a given Einstein Killing scale. For completeness and to introduce the main ideas, we also study analogous questions for conformal Killing vectors.
title Conformal Killing tensors and their Killing scales
topic Differential Geometry
53A30, 53C18, 53A20, 53B15, 70H33, 37K10
url https://arxiv.org/abs/2406.17212