1 citations
4 papers
Spatial vector solitons in nonlinear photonic crystal fibers
Jose R. Salgueiro, Yuri S. Kivshar, Dmitry E. Pelinovsky +2
We study spatial vector solitons in a photonic crystal fiber (PCF) made of a material with the focusing Kerr nonlinearity. We show that such two-component localized nonlinear waves…
Categorical non abelian cohomology, and the Schreier theory of groupoids
V. Blanco, M. Bullejos, E. Faro
By regarding the classical non abelian cohomology of groups from a 2-dimensional categorical viewpoint, we are led to a non abelian cohomology of groupoids which continues to satis…
Postnikov Invariants of Crossed Complexes
M. Bullejos, E. Faro, M. A. García-Muñoz
We determine the Postnikov Tower and Postnikov Invariants of a Crossed Complex in a purely algebraic way. Using the fact that Crossed Complexes are homotopy types for filtered spac…
A Full and faithful Nerve for 2-categories
M. Bullejos, E. Faro, V. Blanco
The notion of geometric nerve of a 2-category (Street, \cite{refstreet}) provides a full and faithful functor if regarded as defined on the category of 2-categories and lax 2-funct…