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222are used to construct a generalized uncertainty relation; the generalized coherent states (CS) being those states for which the uncertainty product is a minimum (MUCS). The states developed in this fashion when sub jected to time evolution are not completely dispersionless as they move in the classical potential but do appear to be capable of a least partly reforming after a few oscillations although, eventually, an initial wave packet will disperse throughout the classically allowed region 10 .An alternate method of creating generalized coherent states for sys tems other than the oscillator is associated with the unitary irreducible representations (UIRs) of Lie groups and Lie algebras 11 . This approach may be considered as complementary to the MUCS discussed above. The most familiar Lie group, SU(2), of course describes a number of systems such as two level atoms, spin systems etc. Coherent states of SU(2) are the subject of Professor Kuratsuji's lectures. On the other hand the noncompact group SU(1,1), which has the following local isomorphisms: SU(1,1) ~ SO(2,l) ~~ Sp(2R) ~ S1(2R), plays the role of dynamical group for a number of systems of general interest. The term dynamical group as used here should be taken as synonymous with the terms noninvariance group and spectrum generating group. Actually it is the spectrum generating algebra (SGA) of the associated dynamical group that is mainly of interest. With the Hamiltonian composed of the generators of the group, the UIRs yield the spectrum from the energy eigenvalue prob lem. Among the systems for which SU(1,1), or one of its isomorphic forms, provides an SGA, are, the harmonic oscillator 12 , the Coulomb problem 13 , Hartmann's 14 ring potential 15 , the s-states of the Morse oscilla tor 16 , the s-states of the Hulthen potential 17 , the Dirac-Coulomb and Klein-Gordon-Coulomb problems 18 . Some many-particle problems are also included. Examples are a model of a superfluid bose system 19 and coupled harmonic oscillators 20 . There recently has been a great deal of interest in the algebraic approach to scattering problems 21 and in the cal culation of resonance widths and positions 22 . Now in constructing coherent states for SU(1,1) we recall that ordi nary oscillator coherent states, {\z>} where z is complex, may be con structed in three ways: i) as states which minimize the uncertainty rela tion AxAp >7T/2, ii) as eigenstates of the annihilation operator a, i.e. a \z> «= z \z> and III) as states displaced from the vacuum |0> by the operation of the displacement o...