https://old.reddit.com/r/math/comments/1b5s32x/the_case_agai...
You may also read other discussions by the author and others at the Reddit post:
https://old.reddit.com/r/math/comments/1b5s32x/the_case_agai...
A few Reddit comments appear to agree at that non-mathematicians (e.g. amateurs and game programmers) use geometric algebra non-rigorously.
I suspect the issue is not about mathematicians who know how to be rigorous. Both posts are complaining about how mathematical outsiders are using and teaching geometric algebra non-rigorously.
When GA has clean formulas for calculating stuff, sure. But should you write all your linear algebra formulas in terms of the geometric product? heck no. For most people GA is their first exposure to wedge products, though, and those actually are great, so they think that's GA. No, that's just ordinary well-known material that should be in linear algebra classes already. What GA adds on top of that is mostly really weird, although there is a kernel of quality inside it somewhere.
i + j is just as silly as 1 + 1.
Anyway, go read a bunch of GA books and papers and you'll see exactly what I'm talking about there. At some point in the past (like ~8 years ago) I think I had read or at least skimmed everything that had ever been published on the subject. And some of it's good! Although at times, like, unnecessary. The rest, though... yikes.
https://news.ycombinator.com/item?id=39576214
> even by the 90s/00s, GA had gotten a bad reputation because of its tendency to attract bad mathematicians and full-on crackpots
> those reasons disproportionately attract people who are not actually capable of rigorous mathematics, or are slightly prone to conspiratorial thinking, or are otherwise slightly deranged
> if you look around for papers that explicitly talk GA, they are very disproportionately (a) non-theoretical, (b) poorly-written, (c) trivial, i.e. restating widely-known results as if they’re novel, (d) only citing other GA papers, and of course (e) just plain crackpotty