On left regular bands and real conic–line arrangements
نویسندگان
چکیده
منابع مشابه
On Left Regular Bands and Real Conic-line Arrangements
An arrangement of curves in the real plane divides it into a collection of faces. Already in the case of line arrangements, this collection can be given a structure of a left regular band and one can ask whether the same is possible for other arrangements. In this paper, we try to answer this question for the simplest generalization of line arrangements, that is, conic–line arrangements. Invest...
متن کاملTHE LEFT REGULAR REPRESENTATION OF A COMMUTATIVE SEPARATIVE SEMIGROUP
In this paper, a commutative semigroup will be written as a disjoint union of its cancellative subsemigroups. Based on this fact we will define the left regular representation of a commutative separative semigroup and show that this representation is faithful. Finally concrete examples of commutative separative semigroups, their decompositions and their left regular representations are given.
متن کاملTopology of real coordinate arrangements
We prove that if a simplicial complex ∆ is (nonpure) shellable, then the intersection lattice for the corresponding real coordinate subspace arrangement A∆ is homotopy equivalent to the link of the intersection of all facets of ∆. As a consequence, we show that the singularity link of A∆ is homotopy equivalent to a wedge of spheres. We also show that the complement of A∆ is homotopy equivalent ...
متن کاملTopology and combinatorics of real line arrangements
We prove the existence of complexified real arrangements with the same combinatorics but different embeddings in P. Such pair of arrangements has an additional property: they admit conjugated equations on the ring of polynomials over Q( √ 5).
متن کاملReal line arrangements and fundamental groups
Let A be a real line arrangement in P(R), and let AC be its complexification. Let CC be the complement P (C) \ ⋃ AC. Let G be the Galois group of C/R. We construct a G-equivariant 2-dimensional strong deformation retract of CC. As an application, we give an explicit presentation of the orbifold fundamental group π1(CC//G), and deduce from it an explicit presentation of the ordinary fundamental ...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Semigroup Forum
سال: 2018
ISSN: 0037-1912,1432-2137
DOI: 10.1007/s00233-018-9966-x