Additive Combinatorics Using Equivariant Cohomology
  We introduce a geometric method to study additive combinatorial problems. Using equivariant cohomology we reprove the Dias da Silva-Hamidoune theorem. We improve a result of Sun on the linear extension of the Erd\H{o}s-Heilbronn conjecture. We generalize a theorem of G. K\'os (the Grashopper problem) which in some sense is a simultaneous generalization of the Erd\H{o}s-Heilbronn conjecture. We also prove a signed version of the Erd\H{o}s-Heilbronn conjecture and the Grashopper problem. Most identities used are based on calculating the projective degree of an algebraic variety in two different ways. 
L\'aszl\'o M. Feh\'er and J\'anos Nagy
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