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From: David Leduc <david.leduc6@googlemail.com>
To: categories <categories@mta.ca>
Subject: Dualizing comma categories
Date: Sun, 30 Oct 2011 12:34:59 +0000	[thread overview]
Message-ID: <E1RKVbv-0005yH-G5@mlist.mta.ca> (raw)

Hi,

A comma category is a comma object in the 2-category Cat of categories
and functors. And a comma object is defined by a universal property.
Now, one can dualize the notion of comma object by turning around the
1-cells and/or 2-cells in its definition. My question is: when we
instantiate those dualized definitions to Cat, what do we obtain? In
other words, what is a "co-comma category"?

For example, since the product of two categories is a special case of
comma category, I would expect that the coproduct of two categories is
a special case of "co-comma category".

Thanks!


[For admin and other information see: http://www.mta.ca/~cat-dist/ ]


             reply	other threads:[~2011-10-30 12:34 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-10-30 12:34 David Leduc [this message]
2011-10-30 22:29 ` Steve Lack
2011-11-01  4:05   ` Michael Shulman

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