A new method to build the (inverse) distance ladder

The cosmic distance ladder is the succession of techniques by which it is possible to determine distances to astronomical objects. Here, we present a new method to build the cosmic distance ladder, going front local astrophysical measurements to the CMB. Instead of relying on high-redshift cosmography in order to model the lumiriosity-distance relation and calibrate supernovae with FAO. we exploit directly the distance-duality relation (d(L) = (1 + z)(2) d(A) - valid if photon limber is conserved and gravity is described by :a metric theory. The :advantage is that the results will not depend on the parametrization of the luminosity distance relation at z > 0.15: no model is adopted in order to calibrate FAO with supernovae. This method yields local measurements of the Hubble constant and deceleration parameter. Furthermore. it can directly assess the impact of 13A0 observations on the strong 4-5 sigma tension between local and global H-0. Using the latest supernova. BAO and CMF observations, we found a consistently low value of q(0) and strong inconsistency between angular-only FAO constraints and anisotropic FAO measurements, which are, or not, in agreement with CMF depending on the kind of analysis (see Table 40. We conclude that. in order to understand the reasons behind the H-0 crisis, a first step should be clarifying the tension between angular and perpendicular anisotropic FAO as this will help understanding if new physics is required at the pre-recombination epoch ortand during the dark energy era,