On Larger $H_0$ Values in the CMB Dipole Direction
  On the assumption that quasars (QSO) and gamma-ray bursts (GRB) represent
\textit{standardisable candles}, we provide evidence that the Hubble constant
$H_0$ adopts larger values in hemispheres aligned with the CMB dipole
direction. If substantiated, this trend signals a departure from FLRW
cosmology. In particular, QSOs show a definite trend, whereas our findings in
GRBs are consistent with an isotropic Universe, but we show in a sample of GRBs
calibrated with Type Ia supernovae (SN) that this conclusion may change as one
focuses on GRBs more closely (mis)aligned with the CMB dipole direction. The
statistical significance in QSOs alone is $\gtrsim 2 \sigma$ and when combined
with similar trends in strong lensing, Type Ia SN and calibrated GRBs, this
increases to $\sim 3 \sigma$. Our findings are consistent with reported
discrepancies in the cosmic dipole and anisotropies in galaxy cluster scaling
relations. The reported variations in $H_0$ across the sky suggest that Hubble
tension may be a symptom of a deeper cosmological malaise.
