From mboxrd@z Thu Jan 1 00:00:00 1970 X-Msuck: nntp://news.gmane.io/gmane.science.mathematics.categories/2443 Path: news.gmane.org!not-for-mail From: "V. Schmitt" Newsgroups: gmane.science.mathematics.categories Subject: Preprint: Flatness, preorders and general metric spaces Date: Thu, 18 Sep 2003 11:56:49 +0100 Message-ID: <3F698F71.9070601@mcs.le.ac.uk> NNTP-Posting-Host: main.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit X-Trace: ger.gmane.org 1241018666 4188 80.91.229.2 (29 Apr 2009 15:24:26 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Wed, 29 Apr 2009 15:24:26 +0000 (UTC) To: categories@mta.ca Original-X-From: rrosebru@mta.ca Fri Sep 19 14:48:19 2003 -0300 Return-path: Envelope-to: categories-list@mta.ca Delivery-date: Fri, 19 Sep 2003 14:48:19 -0300 Original-Received: from Majordom by mailserv.mta.ca with local (Exim 4.10) id 1A0PJL-0004NC-00 for categories-list@mta.ca; Fri, 19 Sep 2003 14:44:51 -0300 User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.0.0) Gecko/20020623 Debian/1.0.0-0.woody.1 X-Accept-Language: en Original-Sender: cat-dist@mta.ca Precedence: bulk X-Keywords: X-UID: 11 Original-Lines: 32 Xref: news.gmane.org gmane.science.mathematics.categories:2443 Archived-At: Dear all, I put a recent paper (just submitted) in the math Arxiv at http://front.math.ucdavis.edu/math.CT/0309209 Your comments are most welcome. Thanks. Vincent. *Title:* Flatness, preorders and general metric spaces *Author:* Vincent Schmitt *Categories:* CT Category Theory *Abstract:* This paper studies a general notion of flatness in the enriched context: P-flatness where the parameter P stands for a class of presheaves. One obtains a completion of a category A by considering the category Flat_P(A) of P-flat presheaves over A. This completion is related to the free cocompletion of A under a class of colimits defined by Kelly. For a category A, for P = P0 the class of all presheaves, Flat_P0(A) is the Cauchy-completion of A. Two classes P1 and P2 of interest for general metric spaces are considered. The P1- and P2-flatness are investigated and the associated completions are characterized for general metric spaces (enrichemnts over R+) and preorders (enrichments over Bool). We get this way two non-symmetric completions for metric spaces and retrieve the ideal completion for preorders.