Julian Gough's extension of Smolin's CNS: when does intelligent-life-created black holes overtake natural stellar production? Universe fitness is the total BH mass density per Mpc³.
This tool implements Julian Gough's three-stage extension of Lee Smolin's Cosmological Natural Selection. Smolin (1992) proposed that our universe's physical constants are optimised by natural selection to maximise black hole production. Gough (2020s) argues there are three distinct production channels, and that in late-time universes the third stage — intelligent life creating BHs — could become the dominant contribution to the total BH yield.
Stage 1 — Direct-collapse SMBHs: In the first ~100 Myr after the Big Bang, massive gas clouds could collapse directly into black holes of 10⁴–10⁹ M☉ without forming stars first. JWST has found evidence for unexpectedly massive BHs at z > 10 (Harikane et al. 2023), which Gough interprets as support for this channel. Number density n_DC is highly uncertain — the tool spans the observational range (10⁻⁶ to 1 per Mpc³).
Stage 2 — Stellar BHs: Massive stars (roughly M > 20 M☉) end their lives as black holes. The Salpeter IMF (dN/dM ∝ M⁻²·³⁵) predicts roughly 0.1–1% of total stellar mass ends up in stellar BHs. Integrated over the cosmic star formation history, the total stellar mass formed is ~5×10⁸ M☉ Mpc⁻³ (Madau & Dickinson 2014), giving a Stage 2 yield of ~10⁶–10⁷ M☉ Mpc⁻³.
Stage 3 — Civilisational BHs (✦): Gough's distinctive addition. Advanced civilisations could create BHs deliberately — via particle accelerator chains reaching Planck energies, engineered supernova triggering, or direct gravitational collapse of structured matter. The parameters here are unconstrained by observation; the tool explores the consequences of different assumptions. M_civ = mass per created BH is a key free parameter: if civilisations create stellar-mass BHs (10–100 M☉), the yield per creation is small; if they create IMBH-scale BHs (10³–10⁵ M☉), the yield is much larger.
In CNS, universe "fitness" is measured by total BH production per unit volume. A universe that produces intelligent life capable of Stage 3 BH creation may be more reproductively fit than one that only runs Stages 1 and 2 — but only if Stage 3 yields are substantial. This creates a potential selection pressure for universes that support life.
Stage 2 calculations are 🔬 — the Salpeter IMF and stellar evolution are well-established. Stage 1 is ⚠ theoretical — supported by some JWST evidence but the model is debated. Stage 3 is ✦ engineering fiction — there is no observational evidence for civilisational BH creation and the parameter range spans many orders of magnitude.
v1.0 — 2026-06-02 · Tool content may be revised as scientific knowledge evolves.