We define a model category structure on a slice category of simplicial spaces, called the "Segal group action" structure, whose fibrant-cofibrant objects may be viewed as representing spaces $X$ with an action of a fixed Segal group (i.e. a group-like, reduced Segal space). We show that this model structure is Quillen equivalent to the projective model structure on $G$-spaces, $S^BG}$, where $G$ is a simplicial group corresponding to the Segal group. One advantage of this model is that if we start with an ordinary group action $X\in S^BG$ and apply a weakly monoidal functor of spaces $L: S \to S$ (such as localization or completion) on each simplicial degree of its associated Segal group action, we get a new Segal group action of $LG$ on $LX$ which can then be rigidified via the above-mentioned Quillen equivalence.
Keywords: Model category, Segal space, group action, equivariant homotopy theory
@article{TAC_2015_30_a39,
author = {Matan Prasma},
title = {Segal group actions},
journal = {Theory and applications of categories},
pages = {1287--1305},
year = {2015},
volume = {30},
language = {en},
url = {http://geodesic.mathdoc.fr/item/TAC_2015_30_a39/}
}
Matan Prasma. Segal group actions. Theory and applications of categories, Tome 30 (2015), pp. 1287-1305. http://geodesic.mathdoc.fr/item/TAC_2015_30_a39/