CS etc

[r_transpose_p]

I'm slowly getting the impression that the field I knew of as "computer science" when I was an undergrad (remember when the undergraduate catalog listed a "scientific computing track"? CS majors don't do that shit anymore) is slowly schisming into a bunch of only-tangentially-related fields

Comments

[r_transpose_p]

I am scared shitless of category theory.

Also : I was mighty pissed when people started using category theory for one of my favorite control theory topics : Hybrid systems are systems in which a discrete computational thing controls discontinuous switching for the dynamics of otherwise continuous control systems. I was all excited about it as a research area because

1. the uses of it are obvious in the 'everything is networked and control is done by embedded computers' world
2. I know a lot more discrete math than most control theorists
3. Its new, and, until recently, nobody had said anything deep about them

Then some fucker* figures out that you can use category theory to transform theorems about non-linear differential equations style control onto theorems about the discrete components of hybrid systems and hybrid systems in general.

Now, if I want to make a big splash in this area, I have to

1. Understand the common category theory transformations being used here
2. Exploit the fact that discrete theorems are easier than continuous theorems and find some useful discrete techniques that don't follow from 300 years of theorems about dynamics
3. Find a use for these theorems, publish a paper using them, and explain why they specifically don't follow from these category theoretic transformations

Most likely what I'll do, if I stay academic, is move on to more practical robotics and ignore these issues...

*Actually he's a really nice guy, we bummed cigarettes from each other at a couple conferences.

[catamorphism]

I'm also somewhat scared of category theory.

In PL, the history of category theory is that some people were all like "Wow, you can use category theory to describe EVERYTHING!" but then practical results of this fact failed to materialize and so most people have moved on. [*]

[*] Flagrantly incomplete and biased history.

[r_transpose_p]

Hey, I give it the benefit of the doubt, cause those things called "functors" in ML are pretty useful things.

I'm a big proponent of the view that "is-a" (a.k.a. "inheritance") is not the only useful relationship between things.

[catamorphism]

The origin of the term "functor" as used in ML is fairly unrelated to the kind of category theory I'm talking about (it originated as a loose analogy, IIUC).

(But some of your other friends would probably know far better than I would.)