Higgs boson conveys mass. Mass is not necessary for a gravity field. Massless particles such as photons can convey both gravity fields and momentum. In short,

Higgs boson conveys mass. Mass is not necessary for a gravity field. Massless particles such as photons can convey both gravity fields and momentum. In short, gravity is correlated with energy density, which coincides with mass (via e=mc2) but the mass itself is not directly responsible for the gravity field, per se.