nLab
enriched model category

Contents

Context

Model category theory

model category

Definitions

Morphisms

Universal constructions

Refinements

Producing new model structures

Presentation of (,1)(\infty,1)-categories

Model structures

for \infty-groupoids

for ∞-groupoids

for equivariant \infty-groupoids

for rational \infty-groupoids

for rational equivariant \infty-groupoids

for nn-groupoids

for \infty-groups

for \infty-algebras

general

specific

for stable/spectrum objects

for (,1)(\infty,1)-categories

for stable (,1)(\infty,1)-categories

for (,1)(\infty,1)-operads

for (n,r)(n,r)-categories

for (,1)(\infty,1)-sheaves / \infty-stacks

Enriched category theory

Contents

Idea

An enriched model category is an enriched category CC together with the structure of a model category on the underlying category C 0C_0 such that both structures are compatible in a reasonable way.

Definition

Let VV be a monoidal model category.

A VV-enriched model category is

The last two conditions here are equivalent to the fact that the copower

:C×VC \otimes : C \times V \to C

is a Quillen bifunctor.

Properties

Change of enrichment

(…)

Examples

Example

(monoidal model category is enriched model over itself)
Every monoidal model category is an enriched model category over itself, via the enrichment of its underlying closed monoidal category.

Proof

One just needs to see that the pullback-power axiom is implied by (in fact it is equivalent to) the pushout-product axiom. This equivalence is an instance of Joyal-Tierney calculus (see this Prop.):

Writing

and

we have the following logical equivalences.

CC C CC FW C FW C FW C FW CCW CW CCW F C F CW F CW FW CW F C F C F \begin{aligned} \mathrm{C} \Box \mathrm{C} & \,\subset\, & \mathrm{C} & \;\;\; \Leftrightarrow \;\;\; & \mathrm{C} \Box \mathrm{C} &\,\;⧄\;\,& \mathrm{FW} & \;\;\; \Leftrightarrow \;\;\; & \mathrm{C} & \,⧄\, & \mathrm{FW}^{\Box \mathrm{C}} & \;\;\; \Leftrightarrow \;\;\; & \mathrm{FW}^{\Box \mathrm{C}} & \,\subset\, & \mathrm{FW} \\ {\phantom{-}} \\ \mathrm{C} \Box \mathrm{CW} & \,\subset\, & \mathrm{CW} & \;\;\; \Leftrightarrow \;\;\; & \mathrm{C} \Box \mathrm{CW} &\,\;⧄\;\,& \!\!\mathrm{F}\;\;\; & \;\;\; \Leftrightarrow \;\;\; & \mathrm{C} & \;⧄\; & \mathrm{F}^{\Box \mathrm{CW}} & \;\;\; \Leftrightarrow \;\;\; & \mathrm{F}^{\Box \mathrm{CW}} & \,\subset\, & \mathrm{FW} \\ & & & & && & \;\;\; \Leftrightarrow \;\;\; & \mathrm{CW} & \;⧄\; & \mathrm{F}^{\Box \mathrm{C}} & \;\;\; \Leftrightarrow \;\;\; & \mathrm{F}^{\Box \mathrm{C}} & \,\subset\, & \mathrm{F} \end{aligned}

Here the outer equivalences are by definition of the lifting properties in a model category, while the middle equivalences are by Joyal-Tierney calculus. The statements on the far left constitute the pushout-product axiom, while those on the far right constiture the pullback-power axiom.

Example

Since the model structure on compactly-generated topological spaces as well as the classical model structure on simplicial sets are monoidal model categories, they are, by by Exp. , also enriched modal categories over themselves.

Example

A model category enriched over the classical model structure on simplicial sets is called a simplicial model category.

References

Textbook account:

See also:

Last revised on October 4, 2021 at 03:24:47. See the history of this page for a list of all contributions to it.