An extension of Wolpert's derivative formula

Authors
Series, C
Citation
C. Series, An extension of Wolpert's derivative formula, PAC J MATH, 197(1), 2001, pp. 223-239
Citations number
10
Categorie Soggetti
Mathematics
Journal title
PACIFIC JOURNAL OF MATHEMATICS
ISSN journal
00308730 → ACNP
Volume
197
Issue
1
Year of publication
2001
Pages
223 - 239
Database
ISI
SICI code
0030-8730(200101)197:1<223:AEOWDF>2.0.ZU;2-0
Abstract
A well known formula of Wolpert expresses the derivative of length of a geo desic gamma on a hyperbolic surface with respect to the Fenchel Nielsen twi st about a fixed simple geodesic C as a sum of the cosines of the intersect ion angles between the two curves. We derive an analogous formula for the d erivative of the length of gamma with respect to variation of the length of the fixed curve C.