A coproduct structure on the formal affine Demazure algebra
  In the present paper we generalize the coproduct structure on nil Hecke rings introduced and studied by Kostant-Kumar to the context of an arbitrary algebraic oriented cohomology theory and its associated formal group law. We then construct an algebraic model of the T-equivariant oriented cohomology of the variety of complete flags. 
Baptiste Calm\`es, Kirill Zainoulline, Changlong Zhong
math.RA math.AG