... homothetic to its dual. This lattice isindimension 1, the A2root lattice (i. e., the hexagonal lattice) in dimension 2, theE8root lattice in dimension 8, and the Leech lattice in dimension 24. ... i. e., isometric with its own dual (in this case,via a rotation). NEW UPPER BOUNDS ON SPHERE PACKINGS I 699Suppose Λ is any lattice of covolume 1, such as an isodual lattice, and fis a radial ... approach to higher di-mensions. One can generalize this function by replacing the sine function witha Bessel function (see Proposition 6.1), but that does not yield a sharp boundin dimensions greater...