A brief math lesson (with knitting content)

****I promise none of the math in this post is scary.  If you have an aversion to math it is okay please keep reading.  No one will get hurt by reading the mathematics that follows...plus you want to see the knitting!****

So I was asked to give a "fun" math talk (20 minutes) to incoming graduate students in a couple of weeks.  So what did I choose?  Geometry of course!  I really like geometry (especially non-Euclidean geometry....not what you learn in high school)  I have found that most grad students have seen very little of this and it is extremely useful (at least in what I do).  

One fun hyperbolic geometry fact:   Triangles must have angle sum (add up the degrees of all three angles) less than 180!  Yes there are geometries where angle sums are more than 180 too! 

So to the knitting.  I thought it would be a shame to give such a talk and not have a nice model of hyperbolic space.  I made a knitted version, but here is also a crocheted version.  (They often look like lettuce because they curve a lot as you go out further)

I made a Pseudosphere (in LSU colors of course) pattern here.  I added a single crocheted border to help the added curling and give it some purple!   I think it will be the perfect model to make my talk more fun!

Not too scary right? :)