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Nov 9, 2009 at 0:52 vote accept Reid Barton
Nov 9, 2009 at 0:51 comment added Reid Barton Corollary B.13 of the reference [HS99] gives examples of what I presume are stable presentable categories without any nonzero compact objects.
Nov 9, 2009 at 0:44 comment added Charles Rezk I don't have a ready example in the case where you drop the hypothesis of compactness. If you form the localization of spectra with respect to a homology theory E, the localization L_E(S) of the sphere spectrum is a generator for this stable homotopy theory, but in general L_E(S) is not compact. But this doesn't preclude the existence of some other compact generator, and that actually happens in some cases, e.g., E= a Morava K-theory.
Nov 9, 2009 at 0:34 history edited Charles Rezk CC BY-SA 2.5
Corrected.
Nov 9, 2009 at 0:33 comment added Charles Rezk Ah. I should have said "compact generators", as that appears the condition Schwede-Shipley require. So "presentable" implies "set of generators", but "compact generators" is much more special.
Nov 9, 2009 at 0:24 comment added Reid Barton I think that "has a set of generators" is implied by "presentable", right?
Nov 9, 2009 at 0:22 history edited Charles Rezk CC BY-SA 2.5
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Nov 9, 2009 at 0:15 history answered Charles Rezk CC BY-SA 2.5