2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/231051In two 1966 papers, Jacques Tits gave a construction of exceptional Lie algebras (hence implicitly exceptional algebraic groups) and a classification of possible indexes of simple algebraic groups. For the special case of his construction that gives groups of type E6, we connect the two papers by answering the question: Given an Albert algebra A and a separable quadratic field extension K, what is the index of the resulting algebraic group?29 pages. For possibly newer versions, see http://www.mathcs.emory.edu/~skip/preprints.htmlGroup TheoryRings and Algebras20G15 (Primary) 17C40, 17B25 (Secondary)text