  A mean-field model of Ising spin glass with the Hamiltonian being a sum of
the infinite-range ferromagnetic and random antiferromagnetic interactions is
studied. It is shown that this model has phase transition in external magnetic
field into inergodic spin glass phase with a number of metastable states. The
thermodynamic properties of metastable states are studied at T=0 and near the
transition. The relations between the characteristics of slow nonequilibrium
processes in spin glass phase (such as hysteresis loop form, thermo-remanent
and isothermal remanent magnetizations, field-cooled and zero-field-cooled
thermodynamic quantities) and thermodynamic parameters of metastable states are
established.
