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Timeline for Internal hom of sheaves

Current License: CC BY-SA 2.5

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May 14, 2010 at 16:19 answer added Urs Schreiber timeline score: 1
Mar 18, 2010 at 11:41 comment added roger123 The "second definition" is from "Sheaves in geometry and logic" "Mac Lane, Moerdijk" I. Proposition 1. and page 136. I don't remember where the first definition is from.
Mar 18, 2010 at 1:51 comment added Steven Gubkin You really shouldn't be defining sheaf hom in any of these ways - you should be defining it by it's universal property. That is the right way to think about it - you have just presented some constructions. How do you verify if your constructions are valid? Check the property. For a very nice treatment of all of this see MacLane's "Sheaves in Geometry and Logic".
Mar 18, 2010 at 0:50 comment added Agustí Roig Sorry roger123, but where do you find "in the literature" the two definitions? Thanks in advance.
Mar 18, 2010 at 0:11 answer added David Carchedi timeline score: 5
Mar 17, 2010 at 11:48 comment added roger123 You are right, Omar. But this is strange: Look at Shafarevic, Basic Algebraic Geometry 2, VI.3.2. Example 2 (page 88). "the dual sheaf ... is the sheafication of the presheaf $G(U)=Hom(F(U),O_X(U))$".
Mar 16, 2010 at 15:54 comment added Omar Antolín-Camarena The third definition you suggest (in the edit) doesn't work: that formula does not define a presheaf; there is no way to define the restriction maps.
Mar 16, 2010 at 13:10 comment added roger123 I made an edit. Perhaps it is better now
Mar 16, 2010 at 13:07 history edited roger123 CC BY-SA 2.5
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Mar 16, 2010 at 11:59 answer added Peter Arndt timeline score: 3
Mar 16, 2010 at 11:48 comment added Andrea Ferretti I don't understand the notation for the second definition.
Mar 16, 2010 at 11:28 history edited roger123 CC BY-SA 2.5
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Mar 16, 2010 at 10:54 history asked roger123 CC BY-SA 2.5