Nonpositive immersions and counting cycles

Jeudi 10 décembre 2015 14:00-15:00 - Daniel T. Wise - McGill & IHP

Résumé : The « nonpositive immersion » property is a condition on a 2-complex X that generalizes being a surface. When X has this property, its fundamental group appears to have has some very nice properties which I will discuss. I will spend the remainder of the talk outlining a proof that the nonpositive immersion property holds for a 2-complex obtained by attaching a single 2-cell to a graph. This was proven recently with Joseph Helfer and also independently by Lars Louder and Henry Wilton.

Lieu : bât 425, salle 121-123

Nonpositive immersions and counting cycles  Version PDF