|Blue calculus||MonCat||2Hilb||Set (as a one object bicategory)|
|Types||monoidal categories||manifolds||2 Hilbert spaces||*|
|Terms with one free variable||monoidal functors||manifolds with boundary||linear functors||sets|
|Rewrite rules||monoidal natural transformation||manifolds with corners||linear natural transformations||functions|
|Tensor product||juxtaposition (disjoint union)||tensor product||cartesian product|
|where is free||formal sum of cobordisms with boundary from to||sum of linear functors||disjoint union|
In the MonCat column, is the categorified version of the tensor product of monoids.
What magical creature lives deep in the earth’s crust and has a horrible lisp? A BATHOLITHK.
Better than This Week from Baez,
Better than Lou Kauffman’s knots,
Better than all of the string theory
Better than Feynman’s graffiti,
Better than Calabi-Yau,
Better than Pauli’s neutrino,
Better than mu and than tau,
Better than Curie, Poincaré,
And Niels and Albert at Solvay
Better than anything except being in love.