English

Winding number and Cutting number of Harmonic cycle

Combinatorics 2018-12-14 v2 Algebraic Topology Numerical Analysis

Abstract

A harmonic cycle λ\lambda, also called a discrete harmonic form, is a solution of the Laplace's equation with the combinatorial Laplace operator obtained from the boundary operators of a chain complex. By the combinatorial Hodge theory, harmonic spaces are isomorphic to the homology groups with real coefficients. In particular, if a cell complex has a one dimensional reduced homology, it has a unique harmonic cycle up to scalar, which we call the \emph{standard harmonic cycle}. In this paper, we will present a formula for the standard harmonic cycle λ\lambda of a cell complex based on a high-dimensional generalization of cycletrees. Moreover, by using duality, we will define the standard harmonic cocycle λ\lambda^*, and show intriguing combinatorial properties of λ\lambda and λ\lambda^* in relation to (dual) spanning trees, (dual) cycletrees, winding numbers w()w(\cdot) and cutting numbers c()c(\cdot) in high dimensions.

Keywords

Cite

@article{arxiv.1812.04930,
  title  = {Winding number and Cutting number of Harmonic cycle},
  author = {Younng-Jin Kim and Woong Kook},
  journal= {arXiv preprint arXiv:1812.04930},
  year   = {2018}
}

Comments

27 pages, 6 figures