Invisible dilaton

We analyse the dynamics of a light scalar field responsible for $\mu$ term Higgs potential and coupled to matter via Higgs-portal mechanism. find that this dilaton model is stable under radiative corrections induced by standard particle masses. When background value stabilised at minimum potential, fluctuations only couple quadratically massive fields preventing direct decay into particles. Cosmologically prior electroweak symmetry breaking, rolls down along its effective before eventually oscillating settling minimum. These oscillations can be origin dark due initial misalignment compared minimum, we that, when mass less than eV scale acts as condensate behaving like on large scales, particles cannot thermalise with thermal bath. As couples in composition-dependent manner scalar, could lead violation equivalence principle aboard satellites such MICROSCOPE experiment next generation tests principle. Local gravitational are evaded thanks weakness quadratic coupling halo, around other sources, these models subject screening akin symmetron