## Quotients of the multiplihedron as categorified associahedra.(English)Zbl 1159.18002

Stasheff’s famous associahedra are polytopes which model coherence relations between associativity homotopies. The sequence of multiplihedra, defined by Iwase and Mimura, model maps preserving such homotopy associative structures up to homotopy.
Formally, the associahedra form a topological operad and homotopy associative structures are represented by spaces equipped with a full action of this operad. In the literature, an $$A_\infty$$-space refers to such a space, equipped with an action of Stasheff’s operad of associahedra, an $$A_\infty$$-map refers to a morphism between $$A_\infty$$-spaces preserving structures up to homotopy.
The author studies quotients of multiplihedra, called composihedra, which model $$A_\infty$$-maps from strict monoids to $$A_\infty$$-spaces. He gives a recursive combinatorial description of these new polytopes and an algorithm to realize them as convex hulls of points in $$\mathbb R^n$$.

### MSC:

 18D50 Operads (MSC2010) 52B11 $$n$$-dimensional polytopes 55P48 Loop space machines and operads in algebraic topology 18D20 Enriched categories (over closed or monoidal categories)

polymake
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