Operády v současné matematice
Operations and cooperations in elliptic cohomology. I: Generalized modular forms and the cooperation algebra.
Operations and co-operations in Morava -theory.
Operations and quantum doubles in complex oriented cohomology theory.
Opérations cohomologiques secondaires
Opérations cohomologiques secondaires (suite)
Opérations d'Adams en K-homologie et applications
Opérations d'Adams sur certains groupes de Grothendieck
Opérations géométriques en cobordisme complexe
Operazioni di Steenrod e teoria degli invarianti modulari per i primi dispari
Optimal bounds for the colored Tverberg problem
We prove a “Tverberg type” multiple intersection theorem. It strengthens the prime case of the original Tverberg theorem from 1966, as well as the topological Tverberg theorem of Bárány et al. (1980), by adding color constraints. It also provides an improved bound for the (topological) colored Tverberg problem of Bárány & Larman (1992) that is tight in the prime case and asymptotically optimal in the general case. The proof is based on relative equivariant obstruction theory.
Optimal decision trees on simplicial complexes.
Orbit projections as fibrations
The orbit projection of a proper -manifold is a fibration if and only if all points in are regular. Under additional assumptions we show that is a quasifibration if and only if all points are regular. We get a full answer in the equivariant category: is a -quasifibration if and only if all points are regular.
Orbit projections of proper Lie groupoids as fibrations
Let be a source locally trivial proper Lie groupoid such that each orbit is of finite type. The orbit projection is a fibration if and only if is regular.
Orbit spaces, Quillen's Theorem A and Minami's formula for compact Lie groups
Let G be a compact Lie group. We present a criterion for the orbit spaces of two G-spaces to be homotopy equivalent and use it to obtain a quick proof of Webb’s conjecture for compact Lie groups. We establish two Minami type formulae which present the p-localised spectrum as an alternating sum of p-localised spectra for subgroups H of G. The subgroups H are calculated from the collections of the non-trivial elementary abelian p-subgroups of G and the non-trivial p-radical subgroups of G. We...
Order complex of ideals in a commutative ring with identity
Order complex is an important object associated to a partially ordered set. Following a suggestion from V. A. Vassiliev (1994), we investigate an order complex associated to the partially ordered set of nontrivial ideals in a commutative ring with identity. We determine the homotopy type of the geometric realization for the order complex associated to a general commutative ring with identity. We show that this complex is contractible except for semilocal rings with trivial Jacobson radical when...
Ordinary and directed combinatorial homotopy, applied to image analysis and concurrency.
Orientability of total spaces of fibre bundles over
Oriented singular homology.
Painlevé equations and complex reflections
We will explain how some new algebraic solutions of the sixth Painlevé equation arise from complex reflection groups, thereby extending some results of Hitchin and Dubrovin-- Mazzocco for real reflection groups. The problem of finding explicit formulae for these solutions will be addressed elsewhere.