Monoidal category

Monoidal functor

Let ๐–ข,๐–ฃ be monoidal categories.1 A functor ๐‘‡ :๐–ข โ†’๐–ฃ is called monoidal iff it is eqquipped with an isomorphism ๐œˆ :๐Ÿ™ โ†’๐‘‡๐Ÿ™ in ๐–ฃ and a natural isomorphism with components ๐›พ๐‘ฅ,๐‘ฆ :๐‘‡๐‘ฅ โŠ—๐‘‡๐‘ฆ โ†’๐‘‡(๐‘ฅ โŠ—๐‘ฆ) in ๐–ฃ๐–ขร—๐–ข, compatible with associativity

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and unitality

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Iff ๐œ– and ๐œ‡ are identities, then ๐‘‡ is called strict monoidal.2 If ๐–ข and ๐–ฃ are braided, then a monoidal functor ๐น :๐–ข โ†’๐–ฃ is said to be braided iff

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commutes for all objects ๐‘ฅ,๐‘ฆ โˆˆ๐–ข.

Examples

See also


#state/tidy | #lang/en | #SemBr

Footnotes

  1. As usual we overload ( โŠ—) and ๐Ÿ™ to denote the tensor products and units of both categories. โ†ฉ

  2. 1966. Closed categories, ยงII.1, p. 473 โ†ฉ