Anthropic Landscape: Cosmological Constant Selection

Multiverse theory only becomes a physical argument, not just a metaphor, when it makes a testable statistical prediction — and the clearest example is Steven Weinberg's anthropic bound on the cosmological constant. This simulator draws thousands of candidate vacua from a flat statistical prior on Λ, the kind of measure a string-theory landscape with an astronomical number of vacua would produce, and applies the real physical selection criterion: a vacuum is habitable only if matter gravity dominates long enough for structure to collapse into galaxies before Λ takes over the expansion. Adjust how many vacua are sampled, how wide the landscape's prior range is, and how early galaxies must form, then resample to watch how a razor-thin anthropically-allowed sliver survives inside an overwhelmingly Λ-dominated landscape — the same reasoning Weinberg used, years before the accelerating universe was actually observed, to predict Λ would be small but not exactly zero.