Dark Matter from $SU(6) \to SU(5) \times U(1)_N$

Abstract

Matter and dark matter are unified under the framework of $SU(6)\to SU(5) \times U(1)_N$. A dark-matter candidate is possible, not because it is stable, but because it has a very long lifetime, in analogy to that of the proton in theories of grand unification. A specific example is presented.