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From: Luc Pellissier <luc.pellissier@lipn.univ-paris13.fr>
To: categories@mta.ca
Subject: Functors arising from a relational Grothendieck construction
Date: Mon, 12 Jun 2017 11:37:45 +0200	[thread overview]
Message-ID: <E1dKwD6-0000jU-1e@mlist.mta.ca> (raw)

Dear Category Theorists,

with my adviser Damiano Mazza and his other student Pierre Vial, we are looking
for a name – or even better, a reference – for the following kind of functors:

Let C and B be two categories, F : C ---> D a functor satisfying, for all
morphisms f:c -> c' in C:
- if Ff = g \circ h, then there exists two morphisms k,l such that
  + f = k \circ l 
  + Fk = g
  + Fl = h
- if Ff = id_a for a certain object a, then f itself is an identity.

These functors arise when applying the Grothendieck construction to relational
presheaves: P : B ---> Rel. Indeed, the category of relational presheaves on B
is equivalent (through the Grothendieck construction) to a category whose
objects are such functors over B.

If anyone could point us in a right direction, it would be much appreciated.

Best,

— Luc

[For admin and other information see: http://www.mta.ca/~cat-dist/ ]


             reply	other threads:[~2017-06-12  9:37 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-06-12  9:37 Luc Pellissier [this message]
2017-06-14  1:41 ` David Yetter
2017-06-16 13:16 ` Thomas Streicher
2017-06-17  5:02   ` Ross Street
2017-06-17  9:27   ` Thomas Streicher
2017-06-23 13:56     ` Luc Pellissier
     [not found] ` <5B931A70-3299-433D-89AC-7DFA8627CC2B@lipn.univ-paris13.fr>
2017-06-24  8:37   ` Thomas Streicher

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