REMARKS ON E11 APPROACH

Abstract

We consider a few topics in E11 approach to superstrings/M-theory: even subgroups (Z2 orbifolds) of En, n = 11, 10, 9 and their connection to Kac–Moody algebras, particularly to EE11 subgroup of E11; possible form of supersymmetry relation in E11; decomposition of first fundamental representation l1 w.r.t. the SO (10, 10) and its square-root at first few levels; particle orbit of l1 ⋉ E11. Possible relevance of coadjoint orbits method is noticed, based on a self-duality form of equations of motion in E11.