Dagger symmetric monoidal category

In the mathematical field of category theory, a dagger symmetric monoidal category is a monoidal category ⟨ C , ⊗ , I ⟩ {\displaystyle \langle \mathbf {C} ,\otimes ,I\rangle } that also possesses a dagger structure. That is, this category comes equipped not only with a tensor product in the category theoretic sense but also with a dagger structure, which is used to describe unitary morphisms and self-adjoint morphisms in C {\displaystyle \mathbf {C} } : abstract analogues of those found in FdHilb, the category of finite-dimensional Hilbert spaces.

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