if anyone has an understanding of the outer product. im having trouble with expanding u^v coordinate wise as shown here:
i know you just need the properties shown in the second image. but i cant figure out how to go from line 1 to line 2 using those properties (line 2 to line 3 i get tho)
— My tags on that poll about people's favorite type of product
Geometric algebra¹ sort of scratches the same itch for me as something like category theory does I think. They're extremely general but can be nicely applied to various parts of computer science that I'm also interested in (mainly graphics programming and functional programming respectively²).
As someone who isn't studying maths formally and is mostly learning this stuff with the help of YouTube, how do people not actually doing a university course in it go about learning higher level maths? YouTube videos are all well and good but they can sometimes leave much to be desired.
I guess I could always just implement them in a program or something – like writing a ray tracer using geometric algebra instead of standard linear algebra and quaternions – but that has the problem of feeling like I'm learning a very specific form of the maths rather than the nice generality of the abstract form that attracted me to it in the first place, and that should probably be understood before concretising.
¹ Is it usually "geometric algebra" or "a geometric algebra"? I still haven't quite gotten used to the way "algebra" is used as a countable noun in parts of maths. Same with people saying stuff like "the lambda calculus" honestly, it just sounds wrong.
² Though in some ways geometric algebra reminds me of functional programming as well, the realisation of how separating out higher grade k-vectors rather than treating them as "pseudo-" works feels like understanding the power of a good type system. Though I will admit that it has made me slightly less confident that I could give an answer to the question "What is a scalar?"
Geometric Algebra is a niche branch/spinoff of Linear Algebra (or a niche application of Clifford Algebras) that I happen to like. This video talks about how it can be used to write a 4D/nD physics engine.