TY - GEN AU - Gálvez López, José Antonio PY - 2022 UR - http://hdl.handle.net/10481/74981 AB - We showthat any compact surface of genus zero inR3 that satisfies a quasiconformal inequality between its principal curvatures is a round sphere. This solves an old open problem by H. Hopf, and gives a spherical version of Simon’s quasiconformal... LA - eng PB - Springer TI - A quasiconformal Hopf soap bubble theorem DO - 10.1007/s00526-022-02222-7 ER -