# nLab sSet-site

### Context

#### $(\infty,1)$-Topos Theory

(∞,1)-topos theory

## Constructions

structures in a cohesive (∞,1)-topos

#### Enriched category theory

enriched category theory

# Contents

## Idea

The notion of $sSet$-site is the incarnation of the notion of (∞,1)-site when (∞,1)-categories are incarnated as simplicially enriched categories.

## Definition

###### Definition

An $sSet$-site is a simplicially enriched category $C$ together with the structure of a site on its homotopy category $Ho(C)$.

This appears as (ToënVezzosi, def. 3.1.1)

## Properties

### Relation to $(\infty,1)$-sites

###### Proposition

Under the identification of simplicially enriched categories with models for (∞,1)-categories, $sSet$-sites correspond to (∞,1)-sites.

Because, as discussed at (∞,1)-site, that is equivalently an (∞,1)-category equipped with the structure of a site on its homotopy category of an (∞,1)-category.

### Relation to $(\infty,1)$-toposes

###### Proposition

For $C$ an $sSet$-site, the local model structure on sSet-presheaves is a presentation of the (∞,1)-topos $Sh_\infty(C)$ over the (∞,1)-site corresponding to $C$

$([C^{op}, sSet]_{loc})^\circ \simeq Sh_\infty(C) \,.$

## References

Revised on March 8, 2014 05:08:25 by Urs Schreiber (82.113.121.169)