Michi’s blog » [MATH198] Multiple lectures posted

## [MATH198] Multiple lectures posted

• November 11th, 2009
• 8:31 pm

I have been remiss in updating here. Since the last time I posted, I have posted:
Lecture 6, featuring some interesting limits and colimits, culminating in the introduction of adjoints.

Lecture 7, featuring the introduction of monads based in adjoints, with the connection between the monoid of endofunctors and the Haskellite specification of monads.

Lecture 8, featuring Eilenberg-Moore algebras, initial algebras for datatype specification, Lambek’s lemma and structural induction and recursion with endofunctor algebras.

### 2 People had this to say...

• beroal
• November 22nd, 2009
• 17:16

Hi. I think that we should use isomorphism (?) in “P(I)=I” and “I = 1 + A×I” in the Lecture 8. Thus clarifying why are we proving that ?f,a? is an isomorphism pair.

• Michi
• November 22nd, 2009
• 17:37

Quite so. I have been somewhat sloppy in my notation choices about whether = denotes equality or isomorphism. I blame the wiki platform.

But yes, the = in the equations P(I) = I and I = 1 + AxI are both supposed to indicate isomorphisms.