Geometric Algebra: Describing the Space we Live In

The first barcamp talk I've been to that, in retrospect, seemed to require degree level mathematics. No warning whatsoever of the level of content. By the second slide we were using imaginary numbers...

Dozens of slides, each with complex equations deriving the pure maths behind vector space. Not for the average oggcamper. No application of this was discussed in the talk, just the maths that got us there.

I have a degree in maths so I understand the content, but it wasn't interesting. It would go over the heads of anyone who doesn't understand the maths.

The history bits and the story about the Hamilton Bridge were interesting but far too brief. It could have been interesting if you'd have gone in to detail on these rather than the equations.

I hope you go on to give a more interesting talk in future - remember your target audience and prepare the talk with them in mind. Also warn people in advance who the talk is aimed at.