This is an old joke that's done the rounds on the internet a few times.
Stephan Rauh gave it a pretty good treatment on his blog last year, in which he concludes that it is indeed nonsense:
Funny thing is it took me a while to figure out that the sentence
really is utter nonsense. Most people immediately dismiss it as a joke
– but they’ll never know for sure. It sounds oh so scientific.
Mathematicians like me know what the words mean, and we know a lot of
weird ways to make sense of them. So my first reaction was “It’s
obviously a joke – but what’s the truth behind it?”.
Well, there’s none. Or rather, there is. You can make the branch
operator a homeomorphic endofunctor living in a Hilbert space by
defining a mapping from the set of all git repositories to the
sequence space ℓ∞. You can achieve this easily by using the byte
representations of the git repository.
You can do even simpler by interpreting the bytes a git repository
consists of as a giant number. Thus every each git repository is an
integer, i.e. an element of Z, which can easily embedded into a
Hilbert space. Unfortunately the operations of the Hilbert space don’t
map to a sensible operations on git repositories.
But still, it sounds intriguing. This much is true: the branch
function is a surjective function mapping a git repository to another.
Let’s use the commit operation as the addition. Obviously, the set
of git repositories form an abelian group, but the branch operator
isn’t a homomorphism. Actually, that’s good news, because it would be
I had a lot of fun this afternoon to find out that almost every word
of the sentence is nonsense:
- branch() isn’t a functor but a function,
- it’s not homomorphic, let alone homeophic,
- it’s hard to see how the Hilbert space is defined and so on.