My thoughts on what the Hubble tension really is, based on George Efstathiou’s “To H0 or not to H0?“, arXiv:2103.08723.
After a while that this subject hadn’t appeared in my blog, this week’s entry is entirely dedicated to the Hubble tension: a new observational update in light of Gaia DR3 parallaxes, an old model being killed, and prospects from future neutron star-black hole mergers. A heads-up that this will be the last entry for 2020, as I’m “going” on holidays. Stay tuned for next year’s entries, “see” you soon, Merry Christmas and Happy New Year!
This week’s entry features a new ACT CMB lensing cross BOSS CMASS galaxies cross-correlation measurement implementing a new tSZ-cleaning procedure, a new update on the H0 tension and in particular how fifth forces could lower the TRGB-calibrated measurement (besides the usual Cepheid-calibrated one), and finally the return of black hole shadows (in asymptotically de Sitter spacetime). Enjoy and stay safe!
