Vacuum energy vs a primordial bare Lambda and vs the conundrum of the $H_0$ tension.

Many studies give a Lorentz-invariant regularization of the energy density of the vacuum of SM particles. Based on that and on well established physics, I find an indirect measure of a positive (large) primordial bare Lambda. It sums to the (negative) cumulative contributions of the vacua of SM particles, to obtain the small effective cosmological constant of the LambdaCDM model. I use the same regularization to consider the possibility that the discrepancy, between early and late determinations of the Hubble constant, may be due to the vacuum of a new particle and try to identify its characteristics.