The Weil-Petersson Kähler form and affine foliations on surfaces

The space of broken hyperbolic structures generalizes the usual Teichmueller space of a punctured surface, and the space of projectivized broken measured foliations likewise generalizes the space of projectivized measured foliations. In this paper, the authors naturally extend the Weil-Petersson Kähler two-form to a corresponding two-form on the space of broken hyperbolic structures, as well as Thurston's symplectic form to a corresponding two-form on the space of broken measured foliations. Proposition 3.1. The map $BH(\Delta)\rightarrow BM(\Delta)$ which assigns to the equivalence class of each broken hyperbolic structure the equivalence class of the associated broken measured foliation is a homeomorphism. Proposition 3.2. The map $f_{\Delta}\colon\widetilde{BH(\Delta)} \rightarrow\widetilde{BM(\Delta)}$ which assigns to each equivalence class of decorated broken hyperbolic structure the equivalence class of the associated decorated broken measured foliation is a homeomorphism. Proposition 4.2. A decorated broken hyperbolic structure is uniquely determined by its collection of lambda lengths of triangle-edge pairs. Theorem 6.2. The Weil-Petersson Kähler form on the Teichmueller space $T$ of $F^s_g$ extends to a two-form $\widetilde{\Omega}$ on the space $\widetilde{BH(\Delta)}$ of decorated broken hyperbolic structure on $(F^s_g,\Delta)$, which induces a two-form $\Omega'$ on the space $\widetilde{Y} =\widetilde{BH(\Delta)}\times(0,\infty)$, which extends continuously to a two-form $\widetilde{\Omega'}$ on $\widetilde{Y}\cup\widetilde{BM_{0}(\Delta)}$. The restriction of this form $\widetilde{\Omega'}$ to the space $\widetilde{BM_0(\Delta)}$ is an extension of Thurston's symplectic form on the space $MF_0$ of compactly supported measured foliations on the surface.

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Field Value
Source ISSN: 0232-704X
Author Papadopoulos, Athanase, Penner, Robert, C.
Maintainer CCSD
Last Updated May 9, 2026, 07:49 (UTC)
Created May 9, 2026, 07:49 (UTC)
Identifier hal-00087469
Language en
contributor Institut de Recherche Mathématique Avancée (IRMA) ; Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS)
creator Papadopoulos, Athanase
date 2005-05-09T00:00:00
harvest_object_id 8833e4e0-0f6a-4cdb-ad10-096b8ca026ec
harvest_source_id 3374d638-d20b-4672-ba96-a23232d55657
harvest_source_title test moissonnage SELUNE
metadata_modified 2025-06-04T00:00:00
relation info:eu-repo/semantics/altIdentifier/arxiv/math/0306370
set_spec type:ART