Categorical semantics

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(Modeling [IMLL])
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See <ref>{{BibEntry|bibtype=book|author=MacLane, Saunders|title=Categories for the Working Mathematician|publisher=Springer Verlag,year=1971,volume=5,series=Graduate Texts in Mathematics}}</ref>for a more detailed introduction to category theory.
 
See <ref>{{BibEntry|bibtype=book|author=MacLane, Saunders|title=Categories for the Working Mathematician|publisher=Springer Verlag,year=1971,volume=5,series=Graduate Texts in Mathematics}}</ref>for a more detailed introduction to category theory.
   
== Modeling [IMLL] ==
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== Modeling [[IMLL]] ==
   
A model of [IMLL] is a ''closed symmetric monoidal category''. We recall the definition of these categories below.
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A model of [[IMLL]] is a ''closed symmetric monoidal category''. We recall the definition of these categories below.
   
 
{{Definition|title=Monoidal category|
 
{{Definition|title=Monoidal category|
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for every objects <math>A</math> and <math>B</math>.
 
for every objects <math>A</math> and <math>B</math>.
 
}}
 
}}
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== References ==
 
== References ==
 
<references />
 
<references />

Revision as of 18:14, 23 March 2009

TODO: why categories? how to extract categorical models? etc.

See [1]for a more detailed introduction to category theory.

Modeling IMLL

A model of IMLL is a closed symmetric monoidal category. We recall the definition of these categories below.

Definition (Monoidal category)

A monoidal category (\mathcal{C},\otimes,I) is a category \mathcal{C} equipped with

  • a functor \otimes:\mathcal{C}\times\mathcal{C}\to\mathcal{C} called tensor product,
  • an object I called unit object,
  • three natural isomorphisms of components

\alpha_{A,B,C}:(A\otimes B)\otimes C\to A\otimes (B\otimes C)
\qquad
\lambda_A:I\otimes A\to A
\qquad
\rho_A:A\otimes I\to A

called respectively associator, left unitor and right unitor,

such that

  • for every objects A,B,C,D in \mathcal{C}, the diagram

commutes,

  • for every objects A and B in \mathcal{C}, the diagrams

commute.

Definition (Braided, symmetric monoidal category)

A braided monoidal category is a category together with a natural isomorphism of components

\gamma_{A,B}:A\otimes B\to B\otimes A

called braiding, such that the two diagrams

UNIQ645f0c0bf88c110-math-0000000E-QINU

commute for every objects A, B and C.

A symmetric monoidal category is a braided monoidal category in which the braiding satisfies

\gamma_{B,A}\circ\gamma_{A,B}=A\otimes B

for every objects A and B.

References

  1. MacLane, Saunders. Categories for the Working Mathematician.
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