Six model categories for directed homotopy

We construct a q-model structure, an h-model structure and an m-model structure on multipointed d-spaces and on flows. The two q-model structures are combinatorial and left determined and they coincide with the combinatorial model structures already known on these categories. The four other model structures (the two m-model structures and the two h-model structures) are accessible. We give an example of multipointed d-space and of flow which are not cofibrant in any of the model structures. We explain why the m-model structures, Quillen equivalent to the q-model structure of the same category, are better behaved than the q-model structures.

Six model categories for directed homotopy Keywords:

d-space , flow , topological model of concurrency , combinatorial model category , accessible model category , locally presentable category , enriched semicategory , enriched non-unital category