Feynman categories: Universal operations and Hopf algebras

Feynman categories: Universal operations and Hopf algebras

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Ralph Kaufmann, IAS
Fine Hall 214

After briefly giving the definition of Feynman categories -a toy example being finite sets and surjections- we will consider other algebraic structures that can be derived for them. The first are universal operations, the probably most known example being the Gerstenhaber structure for Hochschild cochains. The second type of structure are Hopf algebras. Examples here include the Hopf algebras of Connes--Kreimer, Goncharov and Baues.