Definition talk:Composition of Densely-Defined Linear Operators

In what way does this definition add something extra over and above the definitions of composition and densely defined linear operator? --prime mover (talk) 20:46, 26 February 2023 (UTC)

It's specifically mentioned in Rudin. Also I was not sure if we had "partial compositions" here where the range of one function is not necessarily contained in the domain of the other. Definition:Composition of Mappings only seems to do $f : S_1 \to S_2$ composed with $g : S_2 \to S_3$. Caliburn (talk) 21:49, 26 February 2023 (UTC)