Revisiting Stellar Recycling and Metal Enrichment in Low-Density Environments: Implications for Galactic and Cosmic Chemical Evolution

This paper critiques the prevailing assumptions of stellar recycling models, par-ticularly the standard 50 cycles per Gyr enrichment framework, by integrating re-cent observational and theoretical advances. We emphasize the role of low-densityintergalactic regions, environmental variation of the initial mass function (IMF),and the non-uniformity of star formation efficiencies (SFE) in shaping metal en-richment and recycling timelines. Special attention is given to the influence ofmetallicity gradients, radiative feedback, and ISM metallicity feedback loops thataffect subsequent recycling. The findings support a revised, environment-dependentenrichment model with strong implications for cosmological simulations and our un-derstanding of chemical evolution in galaxies and the intergalactic medium.