Clément Vidal's framework: which combinations of fundamental constants support stars, carbon chemistry, long-lived main sequence, and habitable temperatures?
What this tool does
This tool visualises Clément Vidal's life-viability framework from "The Beginning and the End" (2014) and his 2010 arXiv paper on computational analogies for fine-tuned parameters. For each pair of fundamental constants, the tool asks: would a universe with these values support the chain of conditions necessary for life as we know it?
The four life conditions
Each cell in the heatmap scores 0–4 based on how many of the following conditions are met, using simplified but physically motivated criteria drawn from Barrow & Tipler (1986) and Tegmark et al. (2006):
Mode A (α, m_p/m_e): (1) Stars form and fuse hydrogen: requires α in a viable range — too large and electromagnetic repulsion prevents fusion, too small and stars can't radiate. (2) Main sequence lasts >1 Gyr: stellar lifetimes scale roughly as (1/α²). (3) Carbon chemistry possible: both α and the mass ratio must permit triple-alpha and CNO synthesis. (4) Habitable temperatures: stellar luminosity and planetary chemistry constraints on α.
Mode B (G_rel, Λ_rel): (1) Galaxies and stars form before Λ-dominated expansion: requires Λ_rel not too large. (2) Stars exist: requires G_rel not too small (gravity needed for collapse). (3) Stars live long enough: G_rel not too large (over-luminous, short-lived). (4) Stable large-scale structure: both parameters in compatible range.
Mode C (α_s_rel, m_p_rel): (1) Protons stable (no rapid decay): m_p_rel in reasonable range. (2) Deuterium forms in Big Bang nucleosynthesis: requires α_s above threshold. (3) Carbon and oxygen synthesised in stars: triple-alpha requires fine-tuned α_s. (4) Life-supporting chemistry: m_p_rel close to 1 for familiar biochemistry.
Relationship to MonkeyGod and CNS Hyperfecundity
This tool asks "which universes support life?", complementing the MonkeyGod simulator (which asks "what fraction of random universes are fine-tuned for stars?") and the CNS Hyperfecundity Landscape (which asks "which universes produce the most black holes?"). Together they form a triptych of Vidal-inspired tools exploring the parameter space of possible universes.
References
Vidal, C. (2010). arXiv:1002.3905 — Computational and Biological Analogies for Fine-Tuned Parameters
Vidal, C. (2014). The Beginning and the End. Springer. DOI: 10.1007/978-3-319-05062-1
Barrow, J. D. & Tipler, F. J. (1986). The Anthropic Cosmological Principle. OUP.
Tegmark, M. et al. (2006). Phys. Rev. D 73:023505. DOI: 10.1103/PhysRevD.73.023505
v1.0 — 2026-06-02