  We describe our recent lattice study of SU(4) gauge theory with fermions in
the fundamental and sextet representations. In this theory, a new type of
baryon consists of quarks in both representations. The spectrum of these
"chimera baryons" has a straightforward interpretation in terms of a
non-relativistic quark model based on SU(4). Our results are particularly
relevant to composite Higgs models in which the top quark is partially
composite.
