Toward minimal composite Higgs models from regular geometries in bottom-up holography

We study a bottom-up, holographic description of field theory yielding the spontaneous breaking an approximate SO(5) global symmetry to its SO(4) subgroup. The weakly-coupled, six-dimensional gravity dual has regular geometry. One dimensions is compactified on circle that shrinks smoothly zero size at finite value direction, hence introducing physical scale in way mimics effect confinement four-dimensional theory. spectrum small fluctuations bulk fields carrying quantum numbers, which can be interpreted as spin-0 and spin-1 bound states This work supplements earlier publication, focused only singlet states. explore parameter space theory, paying particular attention composite have right numbers identified pseudo-Nambu-Goldstone Bosons (PNGBs). find this model PNGBs are generally heavy, with masses same order other states, indicating presence sizeable amount explicit side. But we also qualitatively new, unexpected result. When dimension field-theory operator inducing close half space-time dimensionality, there exists region lightest scalar both parametrically light comparison all Although known yield metastable classical backgrounds, finding might relevant building Higgs context.