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Flasque model structures for simplicial presheaves

Daniel C. Isaksen
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Abstract

By now it is well known that there are two useful (objectwise or local) families of model structures on presheaves: the injective and projective. In fact, there is at least one more: the flasque. For some purposes, both the projective and the injective structure run into technical and annoying (but surmountable) difficulties for different reasons. The flasque model structure, which possesses a combination of the convenient properties of both structures, sometimes avoids these difficulties.

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Daniel C. Isaksen. 2004-01-13. Flasque model structures for simplicial presheaves. https://arxiv.org/abs/math/0401132

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