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concrete category (Definition)

A concrete category over a category $ \mathcal{B}$ is a category $ \mathcal{A}$ together with a faithful functor $ U:\mathcal{A}\to\mathcal{B}$. (The functor $ U$ is sometimes called the forgetful functor or the underlying functor.)

A concrete category over $ \mathbf{Set}$ is called a construct. (Here $ \mathbf{Set}$ denotes the category of sets.)

This means that in a construct objects can be interpreted as sets and morphisms as maps.

Bibliography

1
J. Adámek, H. Herrlich, and G. Strecker.
Abstract and Concrete Categories.
Wiley, New York, 1990.



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"concrete category" is owned by kompik. [ full author list (3) ]
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Also defines:  forgetful functor, underlying functor
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Cross-references: maps, morphisms, objects, category of sets, functor, faithful functor, category
There are 17 references to this entry.

This is version 6 of concrete category, born on 2006-06-30, modified 2007-06-16.
Object id is 8118, canonical name is ConcreteCategory.
Accessed 2100 times total.

Classification:
AMS MSC18A05 (Category theory; homological algebra :: General theory of categories and functors :: Definitions, generalizations)

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construct vs. concrete category by kompik on 2006-06-30 12:47:40
I removed construct from "Also defines" field, for it caused to redirect here totally irrelevant entries.

As far as I remember, some authors use "concrete category" in the sense as "construct" is used in this entry (an in Adamek-Herrlich-Strecker).

Or am I mistaken?
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