IntroductionCurrently the problem of transferring results of algebraic topology to discrete objects and, in particular, to various categories of digraphs and graphs, is widely investigated. The main technical tools are given by the homotopy theory and various homology theories. We present the basic methods of algebraic topology in graph theory and describe relations between continious and discr...
IntroductionThe stable motivic homotopy categories of schemes are nice ∞-categories, which admit a whole six-functor formalism. For a smooth morphism of schemes f: X→Y over a base S, the usual pullback functor f*: SH(Y)→SH(X) admits a left adjoint f_♯, the additive pushforward; they are packaged in a functor from an ∞-category of spans.Recently, Bachmann and Hoyois discovered a multiplicat...