18 research outputs found
Transverse Lusternik–Schnirelmann category of Riemannian foliations
AbstractThe transverse Lusternik–Schnirelmann category of a foliation is an invariant of foliated homotopy type. In this paper we show that the category of a Riemannian foliation is infinite if there exists a non-compact leaf verifying certain conditions. Examples of the obstruction to construct categorical coverings in such foliations are given
Morita Invariance of Equivariant Lusternik-Schnirelmann Category and Invariant Topological Complexity
We use the homotopy invariance of equivariant principal bundles to prove that
the equivariant -category of Clapp and Puppe is invariant under
Morita equivalence. As a corollary, we obtain that both the equivariant
Lusternik-Schnirelmann category of a group action and the invariant topological
complexity are invariant under Morita equivalence. This allows a definition of
topological complexity for orbifolds
Equivariant topological complexity
We define and study an equivariant version of Farber's topological complexity
for spaces with a given compact group action. This is a special case of the
equivariant sectional category of an equivariant map, also defined in this
paper. The relationship of these invariants with the equivariant
Lusternik-Schnirelmann category is given. Several examples and computations
serve to highlight the similarities and differences with the non-equivariant
case. We also indicate how the equivariant topological complexity can be used
to give estimates of the non-equivariant topological complexity.Comment: v1: 19 pages; v2: 14 pages. Final version, to appear in Algebraic &
Geometric Topolog
Morita Invariance of Invariant Topological Complexity
We show that the invariant topological complexity defines a new numerical invariant for orbifolds.
Orbifolds may be described as global quotients of spaces by compact group actions with finite isotropy groups. The same orbifold may have descriptions involving different spaces and different groups. We say that two actions are Morita equivalent if they define the same orbifold. Therefore, any notion defined for group actions should be Morita invariant to be well defined for orbifolds.
We use the homotopy invariance of equivariant principal bundles to prove that the equivariant A-category of Clapp and Puppe is invariant under Morita equivalence. As a corollary, we obtain that both the equivariant Lusternik-Schnirelmann category of a group action and the invariant topological complexity are invariant under Morita equivalence. This allows a definition of topological complexity for orbifolds.
This is joint work with Andres Angel, Mark Grant and John OpreaNon UBCUnreviewedAuthor affiliation: Wright CollegeFacult