3,220 research outputs found
Minimal stretch maps between hyperbolic surfaces
This paper develops a theory of Lipschitz comparisons of hyperbolic surfaces
analogous to the theory of quasi-conformal comparisons. Extremal Lipschitz maps
(minimal stretch maps) and geodesics for the `Lipschitz metric' are
constructed. The extremal Lipschitz constant equals the maximum ratio of
lengths of measured laminations, which is attained with probability one on a
simple closed curve. Cataclysms are introduced, generalizing earthquakes by
permitting more violent shearing in both directions along a fault. Cataclysms
provide useful coordinates for Teichmuller space that are convenient for
computing derivatives of geometric function in Teichmuller space and measured
lamination space.Comment: 53 pages, 11 figures, version of 1986 preprin
Hyperbolic Structures on 3-manifolds, III: Deformations of 3-manifolds with incompressible boundary
This is the third in a series of papers constructing hyperbolic structures on
all Haken three-manifolds. This portion deals with the mixed case of the
deformation space for manifolds with incompressible boundary that are not
acylindrical, but are more complicated than interval bundles over surfaces.
This is a slight revision of a 1986 preprint, with a few figures added, and
slight clarifications of some of the text, but with no attempt to connect this
to later developments such as groups acting on R-trees, etc.Comment: 19 pages, 4 figure
Hyperbolic Structures on 3-manifolds, II: Surface groups and 3-manifolds which fiber over the circle
Geometrization theorem, fibered case: Every three-manifold that fibers over
the circle admits a geometric decomposition. Double limit theorem: for any
sequence of quasi-Fuchsian groups whose controlling pair of conformal
structures tends toward a pair of projectively measured laminations that bind
the surface, there is a convergent subsequence. This preprint also analyzes the
quasi-isometric geometry of quasi-Fuchsian 3-manifolds. This eprint is based on
a 1986 preprint, which was refereed and accepted for publication, but which I
neglected to correct and return. The referee's corrections have now been
incorporated, but it is largely the same as the 1986 version (which was a
significant revision of a 1981 version).Comment: 32 pages, 6 figures, revision of 1986 preprin
From rubber bands to rational maps: A research report
This research report outlines work, partially joint with Jeremy Kahn and
Kevin Pilgrim, which gives parallel theories of elastic graphs and conformal
surfaces with boundary. One one hand, this lets us tell when one rubber band
network is looser than another, and on the other hand tell when one conformal
surface embeds in another.
We apply this to give a new characterization of hyperbolic critically finite
rational maps among branched self-coverings of the sphere, by a positive
criterion: a branched covering is equivalent to a hyperbolic rational map if
and only if there is an elastic graph with a particular "self-embedding"
property. This complements the earlier negative criterion of W. Thurston.Comment: 52 pages, numerous figures. v2: New example
Three-manifolds, Foliations and Circles, I
This paper investigates certain foliations of three-manifolds that are
hybrids of fibrations over the circle with foliated circle bundles over
surfaces: a 3-manifold slithers around the circle when its universal cover
fibers over the circle so that deck transformations are bundle automorphisms.
Examples include hyperbolic 3-manifolds of every possible homological type. We
show that all such foliations admit transverse pseudo-Anosov flows, and that in
the universal cover of the hyperbolic cases, the leaves limit to sphere-filling
Peano curves. The skew R-covered Anosov foliations of Sergio Fenley are
examples. We hope later to use this structure for geometrization of slithered
3-manifolds.Comment: 60 pages, 10 figure
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