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many-worlds interpretation

n. (context physics English) An interpretation of quantum mechanics that claims to resolve all the "paradoxes" of quantum theory by allowing every possible outcome to every event to define or exist in its own "history" or "world".

Wikipedia
Many-worlds interpretation

The many-worlds interpretation is an interpretation of quantum mechanics that asserts the objective reality of the universal wavefunction and denies the actuality of wavefunction collapse. Many-worlds implies that all possible alternate histories and futures are real, each representing an actual "world" (or "universe"). In layman's terms, the hypothesis states there is a very large—perhaps infinite—number of universes, and everything that could possibly have happened in our past, but did not, has occurred in the past of some other universe or universes. The theory is also referred to as MWI, the relative state formulation, the Everett interpretation, the theory of the universal wavefunction, many-universes interpretation, or just many-worlds.

The original relative state formulation is due to Hugh Everett in 1957. Later, this formulation was popularized and renamed many-worlds by Bryce Seligman DeWitt in the 1960s and 1970s. The decoherence approaches to interpreting quantum theory have been further explored and developed, becoming quite popular. MWI is one of many multiverse hypotheses in physics and philosophy. It is currently considered a mainstream interpretation along with the other decoherence interpretations, collapse theories (including the historical Copenhagen interpretation), and hidden variable theories such as the Bohmian mechanics.

Before many-worlds, reality had always been viewed as a single unfolding history. Many-worlds, however, views reality as a many-branched tree, wherein every possible quantum outcome is realised. Many-worlds reconciles the observation of non- deterministic events, such as random radioactive decay, with the fully deterministic equations of quantum physics.

In many-worlds, the subjective appearance of wavefunction collapse is explained by the mechanism of quantum decoherence, and this is supposed to resolve all of the correlation paradoxes of quantum theory, such as the EPR paradox and Schrödinger's cat, since every possible outcome of every event defines or exists in its own "history" or "world".

Usage examples of "many-worlds interpretation".

Indeed, the mathematics of the many-worlds interpretation yields formal proof that no experiment can reveal the existence of the other worlds contained in the universal superposition.

Well, if we accept causality at all, then it sounds to me like were faced with the disagreement between the Copenhagen school and the Many-Worlds interpretation, Hastings said.

At mine: The Dancing Wu Li Masters, The Stories of Ray Bradbury, Airman's Odyssey, The Aquarian Conspiracy, The Many-Worlds Interpretation of Quantum Mechanics, Western Edible Wildplants, The Trimtab Factor.