[FOM] Dual of a category
Laurent Delattre
nouvid-fom at yahoo.fr
Mon Jan 30 21:30:08 EST 2006
> they are in one-one correspondence); consider, for
> example the Ph.D.
> thesis "A Formal Calculus of Categories" of Mario
> Caccamo, in which the
> formalization of duality "...results in a
> nonstandard notion of
> substitution of terms." The thesis is available
> online at
> http://www.brics.dk/DS/03/7/.
I had a look at this thesis.
Caccamo defines a type system where terms are functors
and types are categories. He assumes the following
syntactic equalities on categories (i.e. types):
C^op^op = C
(C*D)^op = C^op * D^op
[C.D]^op = [C^op, D^op]
I wonder if they could be replaced by typing rules. A
definition of C^op through Cat^op might do the
trick...
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