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The writing is cute and the animations are nice, but none of it makes any sense. I stopped reading at

> It is important to remember that bivectors have a certain redundancy built into them in the sense that s a ⃗ ∧ b ⃗ = a ⃗ ∧ s b ⃗ s a ∧ b = a ∧s b . We can write them using 6 numbers or 3 numbers, but they actually convey 5 degrees of freedom.

Three (real) numbers have three degrees of freedom, by definition. (And nothing about complex numbers was mentioned.) Is this a parody I don’t get? I feel like I have wasted ten minutes on nonsense.



You're right about that being wrong, and the author makes the same mistake consistently, but otherwise it looks correct. Some steps have details elided where it maybe should have been noted that things were being skipped, but with correct results. I think it's wonderfully written and a great exposition.


Thanks, that helps. When I notice errors in the stuff I already know about, it find it hard to trust the other information that’s new to me.


hey, if you have time to detail those mistakes I'd be happy to fix them in the text. Can you email me at mattferraro.dev@gmail.com


He's not talking about the triplet or sextet, he means that a bivector has 5 degrees of freedom.

That isn't correct either though, the basis consists of three unit bivectors, so they have at most 3 degrees of freedom.


author here. I was mistaken about the 5 degrees of freedom bit. Bivectors have three. I'll fix the text tonight. I'm sorry you wasted ten minutes on my nonsense.


Hey, I thought it was wonderfully written. I'm definitely part of your target audience, as I fail to easily grok some algebraic concepts.

Thanks for taking the time to write it, and for making the notation easy to write and understand.




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