The Fast and Furious in JWST high-[formula omitted] galaxies

Abstract

Recent JWST surveys reveal a striking abundance of massive galaxies at cosmic dawn, earlier than predicted by ΛCDM. The implied speed-up in galaxy formation by gravitational collapse is reminiscent of short-period galaxy dynamics described by the baryonic Tully–Fisher relation. This may originate in weak gravitation tracking the de Sitter scale of acceleration adS=cH, where c is the velocity of light and H(z)∝1+z3/2 is the Hubble parameter with redshift z. With no free parameters, this produces a speed-up in early galaxy formation by an order of magnitude with essentially no change in initial galaxy mass function. It predicts a deceleration parameter q0=1−2π/GAadS2=−0.98±0.5, where G is Newton’s constant and A=(47±6)M⊙(km/s)−4 is the baryonic Tully–Fisher coefficient (McGaugh 2012). At 3σ significance, it identifies dynamical dark energy alleviating H0-tension when combined with independent q0 estimates in the Local Distance Ladder. Conclusive determination of q0=dlog(θ(z)H(z))/dz|z=0 is expected from BAO angle θ(z) observations by the recently launched Euclid mission.