From mboxrd@z Thu Jan 1 00:00:00 1970 X-Msuck: nntp://news.gmane.io/gmane.science.mathematics.categories/1760 Path: news.gmane.org!not-for-mail From: Bill Rowan Newsgroups: gmane.science.mathematics.categories Subject: Picard group of a ringoid Date: Sat, 16 Dec 2000 17:21:18 -0800 (PST) Message-ID: <200012170121.eBH1LIP10578@transbay.net> NNTP-Posting-Host: main.gmane.org X-Trace: ger.gmane.org 1241018080 322 80.91.229.2 (29 Apr 2009 15:14:40 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Wed, 29 Apr 2009 15:14:40 +0000 (UTC) To: categories@mta.ca Original-X-From: rrosebru@mta.ca Sun Dec 17 10:11:55 2000 -0400 Return-Path: Original-Received: (from Majordom@localhost) by mailserv.mta.ca (8.11.1/8.11.1) id eBHDX0e24555 for categories-list; Sun, 17 Dec 2000 09:33:00 -0400 (AST) X-Authentication-Warning: mailserv.mta.ca: Majordom set sender to cat-dist@mta.ca using -f Original-Sender: cat-dist@mta.ca Precedence: bulk X-Keywords: X-UID: 33 Original-Lines: 12 Xref: news.gmane.org gmane.science.mathematics.categories:1760 Archived-At: Tensor product gives a monoid structure on the class of isomorphism types of R,R-bimodules, for a ring or ringoid R. Restricting to those elements for which there is a two-sided inverse yields a group. I am inclined to call this the nonabelian Picard group and denote it by NPic(R). If we start with a commutative ring R, then the usual Picard group of R, Pic(R), can be viewed as an abelian subgroup of NPic(R). Has anyone seen this before? Does anyone have some other idea about what this should be called? Bill Rowan