The spectrum of the S5 compactification of the chiral N = 2, D = 10 supergravity and the unitary supermultiplets of U(2,2/4)

The spectrum of the S5 compactification of the chiral N = 2, D = 10 supergravity theory is calculated. The modes on S5 fall into unitary irreducible representations of the D = 5, N = 8 anti-de Sitter supergroup U(2,2/4). These unitary supermultiplets involve fields of spin <=2 with quantised 'mass' eigenvalues. The massless multiplet contains fifteen vector fields, six self-dual and six anti-self-dual anti-symmetric tensor fields. The fields of the massless multiplet are expected to be those of a gauged N = 8 theory in D = 5 with a local gauge group SU(4). (author)