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From: John Baez <baez@math.ucr.edu>
To: categories <categories@mta.ca>
Subject: terminology: dagger and involution
Date: Mon, 26 Feb 2007 08:22:21 -0800	[thread overview]
Message-ID: <E1HMDrk-0001vq-Ll@mailserv.mta.ca> (raw)

Marco wrote:

>what you are calling a "dagger-category", i.e.
>
>    a category equipped with a contravariant involutive
>    endofunctor, which is the identity on objects,
>
>has been called "a category with involution", at least from Burgin
>1969 to Lambek 2001. "Involutive category" has also been used, if
>less.
>
>I think it would be better to come back to the old term, which is
>meaningful, translatable, and old.

There's also a body of work, mainly from mathematical physics, that
calls these categories "star-categories".

But, by now there's enough literature using the term "dagger-categories"
that the genie is out of the bottle.

Best,
jb






             reply	other threads:[~2007-02-26 16:22 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2007-02-26 16:22 John Baez [this message]
2007-02-28  8:19 Marco Grandis
2007-03-01  9:21 V. Schmitt
2007-03-02  3:34 John Baez
2007-03-02 21:53 Robert Seely
2007-03-03  5:15 Peter Selinger

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