Half-maximal extended Drinfel’d algebras

Abstract The extended Drinfel’d algebra (ExDA) is the underlying symmetry of non-Abelian duality in low-energy effective theory string theory. Non-Abelian U-dualities maximal supergravities have been studied well, but there has no study on dualities half-maximal supergravities. We construct ExDA for d ≥ 4. also find an extension homogeneous classical Yang–Baxter equation these theories.