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From: Ohad Kammar <ohad.kammar@ed.ac.uk>
To: Categories List <categories@mta.ca>
Subject: Pullbacks of a family of arrows
Date: Wed, 8 Feb 2012 20:29:08 +0000	[thread overview]
Message-ID: <E1RvVHg-0005jO-QT@mlist.mta.ca> (raw)

What is the standard name for the limit of the diagram consisting of a morphism
f : A --> C
and an I-indexed family of morphisms
g_i : B_i --> C
where I is a set?

This is a slight generalisation of pullbacks. I am really interested
in the terminology for the following notion:

A class of morphisms M is stable under such generalised pullbacks if,
for all such limiting cones
a : P --> A
b_i : P --> B_i
if g_i are all in M, then so is the morphism a : P --> A

(This is a slight generalisation of stability of M under pullbacks.)

Thanks,
Ohad.

-- 
The University of Edinburgh is a charitable body, registered in
Scotland, with registration number SC005336.



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             reply	other threads:[~2012-02-08 20:29 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-02-08 20:29 Ohad Kammar [this message]
2012-02-09 15:02 ` Robin Houston

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