Heavy black hole seeds from domain-wall fluctuations in a first-order cosmological phase transition

This project presents a microphysical mechanism for the formation of heavy primordial black hole seeds (M ~ 10^4-10^6 Msun) from energy-density fluctuations in domain-wall networks during a first-order cosmological phase transition at T ~ 10^4-10^6 GeV. The mechanism naturally produces a broad lognormal seed mass function (sigma_log M ~ 1.1-1.5), contrasting with phenomenological narrow-sigma models and providing testable predictions for high-redshift supermassive black holes observed by JWST, Roman Space Telescope, and LISA. Contains: manuscript (.tex, .bib), compiled PDF, figures, Monte Carlo code, and supplementary documentation.