From mboxrd@z Thu Jan 1 00:00:00 1970 X-Msuck: nntp://news.gmane.io/gmane.science.mathematics.categories/1626 Path: news.gmane.org!not-for-mail From: Lutz Schroeder Newsgroups: gmane.science.mathematics.categories Subject: question on "model functor" Date: Fri, 15 Sep 2000 15:13:52 +0200 Message-ID: <39C22090.5802016D@informatik.uni-bremen.de> NNTP-Posting-Host: main.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Trace: ger.gmane.org 1241017976 32135 80.91.229.2 (29 Apr 2009 15:12:56 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Wed, 29 Apr 2009 15:12:56 +0000 (UTC) To: Categories Original-X-From: rrosebru@mta.ca Fri Sep 15 12:44:53 2000 -0300 Original-Received: (from Majordom@localhost) by mailserv.mta.ca (8.9.3/8.9.3) id LAA26336 for categories-list; Fri, 15 Sep 2000 11:30:40 -0300 (ADT) X-Authentication-Warning: mailserv.mta.ca: Majordom set sender to cat-dist@mta.ca using -f X-Mailer: Mozilla 4.75 [en] (X11; U; SunOS 5.7 sun4m) X-Accept-Language: en Original-Sender: cat-dist@mta.ca Precedence: bulk X-Keywords: X-UID: 12 Original-Lines: 35 Xref: news.gmane.org gmane.science.mathematics.categories:1626 Archived-At: The following question looks so natural that somebody's bound to have looked into it: Does the functor Cat^op ---> CAT A |--> [A,Set] reflect isomorphisms (more generally: limits)? related questions (i.e. ones that would solve the problem or at least help solving it) are -- Are epimorphisms in Cat those functors F:A-->B for which F[A] generates B by composites and inverses of isomorphisms (in B)? -- is the source of all covariant hom-functors an extremal mono-source in CAT? The answers are probably in the literature - but where? Thanks a lot, Lutz Schroeder -- ----------------------------------------------------------------------------- Lutz Schroeder Phone +49-421-218-4683 Dept. of Computer Science Fax +49-421-218-3550 University of Bremen lschrode@informatik.uni-bremen.de P.O.Box 330440, D-28334 Bremen http://www.informatik.uni-bremen.de/~lschrode -----------------------------------------------------------------------------