Guidelines for the Atlas Web Interface 1. Groups: Classical groups of rank <= 8 [SL(n,R) (GL(n) coordinates via coordinates.at) after GL(n)] GL(n,R) [SU(p,q) (same) GL(n)] U(p,q) GL(n,H) Sp(2n,R) Sp(p,q) SO(p,q) SO^*(2n) Complex Classical Groups (rank <=8) (as real groups) [SL(n,C) coordinates.at] GL(n,C) Sp(2n,C) SO(n,C) 2. Parameters (for irreducible and standard representations) For each group there are various options to choose parameters, not all options apply to all groups For some there is a choice of infinitesimal character Infinitesimal character Specify in standard coordinates Q^rank(G) (not necessarily dominant) trivial representation finite dimensional specified by highest weight or infinitesimal character Large discrete series (G equal rank quasisplit) Holomorphic discrete series (G equal rank Hermitian) discrete series given by HC parameter (G equal rank) spherical principal series by infinitesimal character (G split) (quasisplit?) large fundamental series (G quasisplit) all A_q(lambda) with given regular integral infinitesimal character all representations with given infinitesimal character Specify an arbitrary parameter (?): Specify real parabolic M=GL(1,R)^a x GL(2,R)^b x classical GL(1,R): (epsilon,nu) GL(2,R): (k,nu) classical: HC parameter for a discrete series 3. Properties of irreducible representations Given an irreducible representation information is available about it infinitesimal character lowest K-types, given by highest weights in nice coordinates for G(R) connected (what precisely in the disconnected case?: plus/minus only) branching up to given level character formula is_unitary (fast algorithm at regular integral infinitesimal character: test if an A_q(lamba) otherwise is_unitary in equal rank case, unequal rank case will be done soon (I insist) [Weakly fair range?] cuspidal data theta-stable data integral root system tau invariant 4. Properites of standard representations specified by a parameter infinitesimal character composition series lowest K-types and branching as for irreducible representations Jantzen filtration