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arXiv · 2503.22768

Definitive Proof of the Classical Multiverse!

Brian R. La Cour·Noah A. Davis
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Abstract

Recent astonishing experiments with quantum computers have demonstrated unambiguously the existence of a quantum multiverse, where calculations of mind-boggling complexity are effortlessly computed in just a few minutes. Here, we investigate whether a similar computation on a digital computer can demonstrate the existence of a classical multiverse. To this end we describe a classical algorithm for efficiently sampling from a $d^n$-dimensional discrete probability distribution representing $n$ digits of $d$ possible values with strong statistical dependence. Although the full distribution for large $n$ quickly becomes intractable, probabilities for given samples can be computed quite efficiently. This allows us to compute exact empirical linear cross-entropy benchmark (XEB) values. Results on a low-end laptop for $d=2$ show excellent agreement with the true XEB for $n \le 30$ and large positive values of the exact empirical XEB for $n \le 1023$ computed over one million samples. We conclude that classical, as well as quantum, computation occurs in many parallel universes.

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Brian R. La Cour, Noah A. Davis. 2025-03-28. Definitive Proof of the Classical Multiverse!. https://arxiv.org/abs/2503.22768

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