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Matrices, diagrammatically

graphicallinearalgebra.net

1–8 of 8 posts

Re: Matrices, diagrammatically

#4
I am guessing these diagrams are taken from Electrical Engineering and not Quantum Physics.

The blog looks like an expansion of their paper http://arxiv.org/abs/1403.7048v3

Yes! That's where I have seen these diagrams before. They are Hopf algebras, which appear both in Electrical Engineering and Theoretical Physics.

Re: Matrices, diagrammatically

#6
post #4

I am guessing these diagrams are taken from Electrical Engineering and not Quantum Physics. The blog looks like an expansion of their paper http://arxiv.org/abs/1403.7048v3 Yes! That's where I have seen these diagrams before. They are Hopf algebras, which appear both in Electrical Engineering and Theoretical Physics.

Baez discussed the paper on the n-Category Café, and it may be easier for the inexperienced (like me!) to get started there: https://golem.ph.utexas.edu/category/2015/05/props_for_linea... .

Re: Matrices, diagrammatically

#8

I am still trying to wrap my head around this, but the parallels with functional programming are striking.

String diagrams are a way to describe morphisms (think functions) in monoidal categories.

A construction using monoidal categories (or a slight generalisation) can be used to give a categorical model for arrows.

http://bentnib.org/arrows.pdf

This gives rise to these diagrams:

https://www.haskell.org/arrows/