Mathematical universe hypothesis

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In physics and cosmology, the mathematical universe hypothesis (MUH), also known as the ultimate ensemble theory, is a speculative "theory of everything" (TOE) proposed by cosmologist Max Tegmark.^[1][2] According to the hypothesis, the universe is a mathematical object in and of itself. Tegmark extends this idea to hypothesize that all mathematical objects exist, which he describes as a form of Platonism or Modal realism.

The hypothesis has proved controversial. Jürgen Schmidhuber argues that it is not possible to assign an equal weight or probability to all mathematical objects a priori due to there being infinitely many of them. Physicists Piet Hut and Mark Alford have suggested that the idea is incompatible with Gödel's first incompleteness theorem.

Tegmark replies that not only is the universe mathematical, but it is also computable.