Kazhdan's property $\mathrm {(T)} $. We will show that no separable $\mathrm {II} _1 $-
factor can contain all these groups in its unitary group. In particular, no separable $\mathrm
{II} _1 $-factor can contain all separable $\mathrm {II} _1 $-factors in it. We also show that the
full group $ C^* $-algebras of some of these groups fail the lifting property. References