Large Number Coincidences and the Anthropic Principle in Cosmology
Brandon Carter · 1974
"Several of the universe's fundamental physical constants appear implausibly fine-tuned for the emergence of life — but this isn't necessarily evidence of design, because any universe where observers exist to notice the constants will, by definition, have constants compatible with observers existing."
Carter's paper, presented in 1973 and published in 1974, formalized an observation physicists had noticed informally: numbers like the strength of gravity relative to electromagnetism, or the precise ratios governing stellar formation, sit in an extremely narrow range — if they were even slightly different, stars, chemistry, or stable planets, and therefore anyone around to measure them, likely couldn't exist. Carter's key move was pointing out a subtle selection effect: we should expect to find ourselves in a universe compatible with our own existence, no matter how statistically rare such a universe is among all possible ones, simply because we couldn't be observing it otherwise.
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Are You Living in a Computer Simulation?
"At least one of three propositions must be true: civilizations almost never reach the technological stage capable of running ancestor-simulations, or those that reach it choose not to run them, or we are almost certainly living inside a simulation ourselves — and there's no principled way to rule out the third."