Inspired by Victor J. Stenger (2011)

MonkeyGod Universe Sampler

Randomly sample universes across the space of physical constants. What fraction permit stars, life, and black holes? The answer depends critically on how wide you draw the sampling range — which is itself the heart of the fine-tuning debate.

Toy model. This simulation uses simplified physics: four constants (G, α, Λ, m_p/m_e), a Gaussian fitness function, and qualitative life/BH thresholds. Real fine-tuning calculations require full stellar evolution codes, nuclear network computations, and many more parameters. Stenger's original MonkeyGod was similarly simplified; Barnes (2012) identifies specific ways it undercounts fine-tuning. Results here are illustrative of the debate, not definitive.
Sampling parameters
10,000
Stenger used ~±2 OOM. Barnes argued ±10 OOM is more appropriate — the range assumption drives the result.
0%
—
Sterile
(no stars)
—
Star-forming
(no life)
—
Life-permitting
(fitness ≥ 0.5)
—
Hyper-fecund
(BH rate > ours)
Distribution of CNS fitness scores — log₁₀(BH production relative to our universe)
Sterile (fitness < 0.01)
Star-forming (0.01–0.5)
Life-permitting (0.5–1.0)
Hyper-fecund (>1.0)
Our universe
Run the simulation to see results.
References
Stenger, V. J. (2011). The Fallacy of Fine-Tuning: Why the Universe Is Not Designed for Us. Prometheus Books. (Primary MonkeyGod source.) Barnes, L. A. (2012). "The Fine-Tuning of the Universe for Intelligent Life." Publications of the Astronomical Society of Australia, 29, 529–564. doi:10.1017/pas.2012.029 (Detailed critique of Stenger's MonkeyGod, identifying specific physical errors.) Smolin, L. (1992). "Did the Universe Evolve?" Classical and Quantum Gravity, 9, 173–191. (Original CNS hypothesis.) Vidal, C. (2014). The Beginning and the End: The Meaning of Life in a Cosmological Perspective. Springer. doi:10.1007/978-3-319-05062-1