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Re:Braided Arithmetic by MarkusQ on Monday November 24, 2025 @10:36AM (#46035213)
Nice presentation. I would probably have written it as an additive group (and then shown that the two strand braid was isomorphic with ℤ) as a further bidirectional intuition anchor (both "look, this new thing relates to something you are familiar with" and "this thing you are familiar with generalizes in unexpected ways").

Definitely liked the exploration of how theorems arise from speculation, and don't spring fully formed straight from Zeus's forehead.

Re:Braided Arithmetic by geordiew on Monday November 24, 2025 @04:45PM (#46039755)
the problem with additive notation is that the braid group isn't commutative when number of strands is > 2.
Re:Braided Arithmetic by MarkusQ on Monday November 24, 2025 @05:38PM (#46040251)
Excellent point. I tend to enjoy "garden path" pedagogy, leading the students to surprising twists and having them explore -- but it's important to lead and not mislead. So yeah, multiplicative notation is probably better.