From: Andree Ehresmann <andree.ehresmann@u-picardie.fr>
To: Categories <categories@mta.ca>
Subject: Partial answer to Jean Benabou
Date: Wed, 11 Jan 2006 19:00:53 +0100 [thread overview]
Message-ID: <E1EwqpI-0003Ar-TO@mailserv.mta.ca> (raw)
In answer to the question raised by Jean:
>if C is a category, what does one need to assume on a subcategory
V of C to be able to construct an analogous C/V and what structure does
it inherit ?
Charles Ehresmann had studied the problem of the existence of a quotient =
(or at
least 'quasi-quotient') category of a category by a sub-category, which h=
ad led
to the introduction of the notion of a "proper subcategory" (generalizing
distinguished sub-groups). His results, summarized in a Note (CRAS Paris=
260,
2116) are developed in the paper on non-abelian cohomology "Cohomologie a
valeurs dans une categorie dominee" (Collloque Topologie Bruxelles, CBRM =
1866)
. Both papers are reprinted in "Charles Ehresmann: Oeuvres completes et
commentees" Part III-2 (and partially taken back in his book "Categories =
et
structures", Dunod 1965).
With all my best wishes
Andree Ehresmann.
next reply other threads:[~2006-01-11 18:00 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2006-01-11 18:00 Andree Ehresmann [this message]
2006-01-15 2:03 ` James Stasheff
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