In
topology
In mathematics, topology (from the Greek words , and ) is concerned with the properties of a geometric object that are preserved under continuous deformations, such as stretching, twisting, crumpling, and bending; that is, without closing ...
, a branch of mathematics, a lamination is a :
* "
topological space
In mathematics, a topological space is, roughly speaking, a geometrical space in which closeness is defined but cannot necessarily be measured by a numeric distance. More specifically, a topological space is a set whose elements are called po ...
partitioned into subsets"
* decoration (a structure or property at a point) of a
manifold in which some subset of the manifold is partitioned into sheets of some lower dimension, and the sheets are locally
parallel
Parallel is a geometric term of location which may refer to:
Computing
* Parallel algorithm
* Parallel computing
* Parallel metaheuristic
* Parallel (software), a UNIX utility for running programs in parallel
* Parallel Sysplex, a cluster of ...
.
A lamination of a surface is a
partition
Partition may refer to:
Computing Hardware
* Disk partitioning, the division of a hard disk drive
* Memory partition, a subdivision of a computer's memory, usually for use by a single job
Software
* Partition (database), the division of a ...
of a closed subset of the surface into smooth curves.
It may or may not be possible to fill the gaps in a lamination to make a
foliation
In mathematics (differential geometry), a foliation is an equivalence relation on an ''n''-manifold, the equivalence classes being connected, injectively immersed submanifolds, all of the same dimension ''p'', modeled on the decomposition of ...
.
[ Oak Ridge National Laboratory]
Examples
*A
geodesic lamination of a 2-dimensional
hyperbolic manifold
In mathematics, a hyperbolic manifold is a space where every point looks locally like hyperbolic space of some dimension. They are especially studied in dimensions 2 and 3, where they are called hyperbolic surfaces and hyperbolic 3-manifolds, res ...
is a closed subset together with a foliation of this closed subset by geodesics. These are used in
Thurston's classification of elements of the
mapping class group
In mathematics, in the subfield of geometric topology, the mapping class group is an important algebraic invariant of a topological space. Briefly, the mapping class group is a certain discrete group corresponding to symmetries of the space.
Mo ...
and in his theory of
earthquake maps.
*Quadratic laminations, which remain invariant under the angle
doubling map. These laminations are associated with
quadratic maps. It is a closed collection of chords in the unit disc.
Modeling Julia Sets with Laminations: An Alternative Definition by Debra Mimbs
It is also topological model of Mandelbrot or Julia set
In the context of complex dynamics, a branch of mathematics, the Julia set and the Fatou set are two complementary sets (Julia "laces" and Fatou "dusts") defined from a function. Informally, the Fatou set of the function consists of values wi ...
.
See also
* train track (mathematics)
In the mathematical area of topology, a train track is a family of curves embedded on a surface, meeting the following conditions:
#The curves meet at a finite set of vertices called ''switches''.
#Away from the switches, the curves are smooth an ...
* Orbit portrait
Notes
References
Conformal Laminations Thesis by Vineet Gupta, California Institute of Technology Pasadena, California 2004
Topology
Manifolds
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