Cold-mode free-fall accretion required for JWST-observed early SMBHs above 10^6 solar masses

The paper models first-order mass supply to seed black holes at halo centers, contrasting cold-mode streams that reach the center unshocked against shock-heated virialized gas. For the latter, required halo abundances exceed observed number densities by orders of magnitude; cold-mode inflow in ~1 Gpc^{-3} halos simultaneously reproduces both the space density of luminous quasars and the masses of 10^7 solar-mass black holes needed to match Little Red Dot counts. This links the decline of LRDs at lower redshift to the shutdown of cold streams once halos grow massive enough for stable virial shocks.

JWST data already show LRD number densities peaking near z~6-8 and falling sharply, consistent with the predicted transition. The model further ties these populations to the underlying halo mass function, implying that the same rare peaks that host the first massive quasars also produce the compact AGN-like sources now classified as LRDs. No additional seeding mechanisms beyond standard Pop III remnants are invoked.

The analysis rests on analytic accretion-rate limits rather than full hydrodynamical simulations, leaving open whether feedback or angular-momentum barriers can throttle even cold streams. Upcoming wide-field JWST surveys that measure the bright-end quasar luminosity function at z>8 and ALMA constraints on cold-gas reservoirs in LRD hosts can test the predicted halo abundance thresholds within the next two years.