From: "Hans-Peter Stricker" <stricker@epublius.de>
To: <categories@mta.ca>
Subject: Examples for the Yoneda lemma
Date: Fri, 15 Jan 2010 01:24:52 +0100 [thread overview]
Message-ID: <E1NVc0f-0007c0-QE@mailserv.mta.ca> (raw)
Hello,
I am looking for (simple) instructive examples for the Yoneda lemma, showing
how to get the "inner" structure of an object from its morphisms. I've been
told how to get a graph G from its morphisms (from the one-vertex-graph V to
G and the one-edge-graph E to G and the morphisms from V to E) and
appreciated this example a lot. Are there others equally simple and
enlightening?
What I wonder is which morphisms are definitely needed. In the graph example
it's the morphisms from V -> G, E -> G and V -> E? Can this be abstracted
and generalized?
Many thanks in advance
Hans-Stricker
[For admin and other information see: http://www.mta.ca/~cat-dist/ ]
next reply other threads:[~2010-01-15 0:24 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-01-15 0:24 Hans-Peter Stricker [this message]
2010-01-15 3:57 ` Steve Lack
2010-01-15 4:45 ` Vaughan Pratt
2010-01-15 11:07 ` Aleks Kissinger
[not found] ` <46ffa45f1001150307r793d81c6s7963324885fba107@mail.gmail.com>
2010-01-15 12:50 ` Hans-Peter Stricker
[not found] ` <E97707B8557E49B5B2FF24D048FCF54C@YOLATENGO>
2010-01-15 13:01 ` Aleks Kissinger
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