This paper challenges the widely held belief in the Many-Worlds Interpretation (MWI) of quantum mechanics, which posits that an infinite multiverse guarantees the repetition of identical universes. Instead, we draw on principles from chaos theory, combinatorics, and measure theory, to argue that even within an infinite multiverse, the probability of encountering an identical universe is effectively zero. Instead, we propose a multiverse characterized by infinite variety, where each universe evolves uniquely due to the sensitivity of initial conditions. This argument not only refutes the MWI's concept of repetition but also has profound implications for the philosophy of identity, individuality, and free will.
This paper challenges the widely held belief in the Many-Worlds Interpretation (MWI) of quantum mechanics, which posits that an infinite multiverse guarantees the repetition of identical universes. Instead, we draw on principles from chaos theory, combinatorics, and measure theory, to argue that even within an infinite multiverse, the probability of encountering an identical universe is effectively zero. Instead, we propose a multiverse characterized by infinite variety, where each universe evolves uniquely due to the sensitivity of initial conditions. This argument not only refutes the MWI's concept of repetition but also has profound implications for the philosophy of identity, individuality, and free will.
Abstract: This paper challenges the widely held belief in the Many-Worlds Interpretation (MWI) of quantum mechanics, which posits that an infinite multiverse guarantees the repetition of identical universes. Instead, we draw on principles from chaos theory, combinatorics, and measure theory, to argue that even within an infinite multiverse, the probability of encountering an identical universe is effectively zero. Instead, we propose a multiverse characterized by infinite variety, where each universe evolves uniquely due to the sensitivity of initial conditions. This argument not only refutes the MWI's concept of repetition but also has profound implications for the philosophy of identity, individuality, and free will.
The Infinite Mirror Hypothesis questions the collapse of self-identity that occurs when the logic of the Many-Worlds Interpretation (MWI)—which claims that "all possibilities are realized"—is taken to its ultimate conclusion. In the Many-Worlds Interpretation, the universe branches infinitely at every choice and every moment. As a result, the existence of "I" is infinitely duplicated, reflecting endlessly like images in a mirror. Starting from the simple question "Why don't time travelers from the future come to us?", this hypothesis points out that while the Many-Worlds Interpretation is "a theory that affirms everything," it is actually "a theory that can specify nothing." Keywords: Many-Worlds Interpretation, Self-Identity, Time Travel, Interpretation of Quantum Mechanics, Philosophy
We present the case for a fixed, finite number of discrete, non-interacting, spatiotemporally finite, decohered spacetimes emerging from Everett’s Universal Wave Function, which we refer to as “Many Discrete Worlds” (MDW). No universes “split” in MDW. We argue that a Many Worlds Interpretation (MWI) branching structure that emerges after decoherence is equivalent to individual, weighted universes, each of which is divided into an immense number of discrete, identical copies, the number being proportional to the individual weighting. This ensures that repeated experiments within any such universe will demonstrate consistency with the Born rule. Each of these universes should be considered as complete, containing every decohered outcome over the entire extent of its spacetime, including every event/interaction occurring beyond any cosmological particle horizon for the entire duration of the given universe. We show that a countably infinite number of interactions needs an uncountably infinite number of universes, and show why measures such as the Lebesgue measure will fail in that case, with the result that the Born rule would not be demonstrable. This leads to the conclusion that the number of universes in the multiverse must be finite and, as a surprising corollary, that the universes themselves are finite, both in space and duration.
We present the case for a fixed, finite number of discrete, non-interacting, spatiotemporally finite, decohered spacetimes emerging from Everett’s Universal Wave Function, which we refer to as “Many Discrete Worlds” (MDW). No universes “split” in MDW. We argue that a Many Worlds Interpretation (MWI) branching structure that emerges after decoherence is equivalent to individual, weighted universes, each of which is divided into an immense number of discrete, identical copies, the number being proportional to the individual weighting. This ensures that repeated experiments within any such universe will demonstrate consistency with the Born rule. Each of these universes should be considered as complete, containing every decohered outcome over the entire extent of its spacetime, including every event/interaction occurring beyond any cosmological particle horizon for the entire duration of the given universe. We show that a countably infinite number of interactions needs an uncountably infinite number of universes, and show why measures such as the Lebesgue measure will fail in that case, with the result that the Born rule would not be demonstrable. This leads to the conclusion that the number of universes in the multiverse must be finite and, as a surprising corollary, that the universes themselves are finite, both in space and duration.
This unpublished 1990 preprint argues that a crucial distinction in discussions of the many-worlds interpretation of quantum mechanics (MWI) is that between versions of the interpretation positing a physical multiplicity of worlds, and those in which the multiplicity is merely psychological, and due to the splitting of consciousness upon interaction with amplified quantum superpositions. It is argued that Everett's original version of the MWI belongs to the latter class, and that most of the criticisms leveled against the MWI, in particular that it is illogical or incoherent, are not valid against such "psychological-multiplicity" versions. Attempts to derive the quantum-mechanical probabilities from the many-worlds interpretation are reviewed, and Everett's initial derivation is extended in an attempt to show that these are the unique possible probabilities. But there remains a challenge for proponents of the MWI: to show that their interpretation requires probabilities, rather than merely nonprobabilistic indeterminacy. A 2002 preface, revised in 2004, briefly discusses the extent to which I still agree with the claims in the paper. While its derivation of probabilities used, and failed to justify, noncontextuality, I still agree with the paper's general interpretation of the MWI, though not with the MWI itself.
We argue that the many worlds of quantum mechanics and the many worlds of the multiverse are the same thing, and that the multiverse is necessary to give exact operational meaning to probabilistic predictions from quantum mechanics. Decoherence---the modern version of wave-function collapse---is subjective in that it depends on the choice of a set of unmonitored degrees of freedom, the environment. In fact decoherence is absent in the complete description of any region larger than the future light cone of a measurement event. However, if one restricts to the causal diamond---the largest region that can be causally probed---then the boundary of the diamond acts as a one-way membrane and thus provides a preferred choice of environment. We argue that the global multiverse is a representation of the many worlds (all possible decoherent causal diamond histories) in a single geometry. We propose that it must be possible in principle to verify quantum-mechanical predictions exactly. This requires not only the existence of exact observables but two additional postulates: a single observer within the Universe can access infinitely many identical experiments; and the outcome of each experiment must be completely definite. In causal diamonds with a finite surface area, holographic entropy bounds imply that no exact observables exist, and both postulates fail: experiments cannot be repeated infinitely many times; and decoherence is not completely irreversible, so outcomes are not definite. We argue that our postulates can be satisfied in hats (supersymmetric multiverse regions with vanishing cosmological constant). We propose a complementarity principle that relates the approximate observables associated with finite causal diamonds to exact observables in the hat.