Electroweak Symmetry Breaking with Non-Universal Scalar Soft Terms and Large $\tan\beta$ Solutions

We discuss radiative electroweak symmetry breaking with non-universal scalar masses at the GUT scale. Large $\tan\beta$ solutions are investigated in detail and it is shown that qualitatively new (as compared to the universal case) solutions exist, with much less correlation between soft terms. We identify two classes of non-universalities which give solutions with $A_o\simeq B_o\simeq M_{1/2}\simeq O(M_Z)$, $\mu \simeq O(0.5 m_o)$, $m_o>>M_Z$ and $A_o\simeq B_o\simeq M_{1/2} \simeq\mu\simeq O(M_Z)$, $m_o\ge M_Z$, respectively. In each case, after imposing gauge and Yukawa coupling unification, we discuss the predictions for $m_t$, $m_b$ and the spectrum of supersymmetric particles. One striking consequence is the possibility of light charginos and neutralinos which in the second option can be higgsino-like. Cosmological constraint on the relic abundance of the lightest neutralino is also included.