English

Harmonic maps and shift-invariant subspaces

Functional Analysis 2019-10-16 v3 Differential Geometry

Abstract

We investigate in detail the connection between harmonic maps from Riemann surfaces into the unitary group \U(n)\U(n) and their Grassmannian models: these are families of shift-invariant subspaces of L2(S1,\Cn)L^2(S^1,\C^n). With the help of operator-theoretic methods we derive a criterion for finiteness of the uniton number which has a large number of applications discussed in the paper.

Keywords

Cite

@article{arxiv.1812.09379,
  title  = {Harmonic maps and shift-invariant subspaces},
  author = {Alexandru Aleman and Rui Pacheco and John C. Wood},
  journal= {arXiv preprint arXiv:1812.09379},
  year   = {2019}
}

Comments

Treatment of Grassmannian model clarified and relation with work of M. Guest added

R2 v1 2026-06-23T06:54:09.961Z