A null test of the Cosmological Principle with BAO measurements
  The assumption of a Friedmann-Lema\^itre-Roberton-Walker (FLRW) Universe is
one of the fundamental pillars of modern Cosmology. It is crucial to confront
it against cosmological observations in order to confirm (or rule out) the
validity of the $\Lambda$CDM paradigm. We perform a consistency test of the
FLRW metric using measurements of both radial and transversal modes of Baryonic
Acoustic Oscillations in a model-independent fashion using Gaussian Processes.
The impact of different prior assumptions for the sound horizon scale and the
Hubble Constant is also explored. We find a mild deviation of the FLRW
hypothesis ($\gtrsim 3\sigma$ confidence level) at lower redshift ranges
($0.1<z<0.3$) under the assumption the SH0ES $H_0$ prior, which does not occur
for the $H_0$ prior by Planck. We also find that different reconstruction
kernels reduce the statistical significance of such a deviation. At higher
reshift ranges, the null test are able to confirm the FLRW assumption within
$3\sigma$ confidence level regardless of the priors.
