• On Weak Weighted Estimates of Martingale Transform 

      [OWP-2016-22] Nazarov, Fedor; Reznikov, Alexander; Vasyunin, Vasily; Volberg, Alexander (Mathematisches Forschungsinstitut Oberwolfach, 2016-11-12)
      We consider several weak type estimates for singular operators using the Bellman function approach. We disprove the $A_1$ conjecture, which stayed open after Muckenhoupt-Wheeden's conjecture was disproved by Reguera-Thiele.