The art of building a smooth cosmic distance ladder in a perturbed
  universe
  How does a smooth cosmic distance ladder emerge from observations made from a
single location in a lumpy Universe? Distances to the Type Ia supernova (SN1A)
in the Hubble flow are anchored on local distance measurements to sources that
are very nearby. We described how this configuration could be built in a
perturbed universe where lumpiness is described as small perturbations on top
of a flat Friedmann-Lema{\i}tre Robertson-Walker (FLRW) spacetime. We show that
there is a non-negligible modification (about 11\%) to the background FLRW area
distance due to the presence of inhomogeneities in the immediate neighbourhood
of an observer. We find that the modification is sourced by the electric part
of the Weyl tensor indicating a tidal deformation of the local spacetime of the
observer. We show in detail how it could impact the calibration of the SN1A
absolute magnitude in the Hubble flow. We show that it resolves the SN1A
absolute magnitude and Hubble tensions simultaneously without the need for
early or late dark energy.
