%0 Journal Article %T Homotopy units in A-infinity algebras %A Fernando Muro %J Mathematics %D 2011 %I arXiv %X We show that the canonical map from the associative operad to the unital associative operad is a homotopy epimorphism for a wide class of symmetric monoidal model categories. As a consequence, the space of unital associative algebra structures on a given object is up to homotopy a subset of connected components of the space of non-unital associative algebra structures. %U http://arxiv.org/abs/1111.2723v4