This paper examines personal identity in the context of the Everett interpretation of Quantum Mechanics. According to Everett, the universe branches many – perhaps an infinite number of – times per second. This leads to a universe in which many versions of ‘you’ exist, many of whom are living different lives to yours. How are we to make sense of the continuation of the self in this context? This is of particular importance for Christian theism, which is committed to an enduring self that can be held responsible for past actions and can develop an ongoing relationship with God. The paper argues that the best way to understand identity in the Everettian world as fundamentally narrative in nature.
This paper examines personal identity in the context of the Everett interpretation of Quantum Mechanics. According to Everett, the universe branches many – perhaps an infinite number of – times per second. This leads to a universe in which many versions of ‘you’ exist, many of whom are living different lives to yours. How are we to make sense of the continuation of the self in this context? This is of particular importance for Christian theism, which is committed to an enduring self that can be held responsible for past actions and can develop an ongoing relationship with God. The paper argues that the best way to understand identity in the Everettian world as fundamentally narrative in nature.
Theological engagement with quantum mechanics has been dominated by the Copenhagen interpretation, failing to reflect the fact that philosophers and physicists alike are increasingly moving away from the Copenhagen interpretation in favor of other approaches. One such approach, Hugh Everett's so‐called Many Worlds Interpretation (MWI), is being taken increasingly seriously. As the MWI's credibility grows, it is imperative that metaphysicians, theologians, and philosophers of religion engage with its ideas and their implications. This article does just that, setting out some implications of Everettian Quantum Mechanics that are particularly relevant to theism. It argues that taking seriously the radical consequences of the Everett interpretation means facing at least three major worries for theism pertaining to personal identity, the problem of evil, and salvation. The article concludes by calling on theologians and philosophers of religion to address these worries, in order that these matters of religious significance remain both coherent and credible if the MWI turns out to be correct.
The Many Worlds Interpretation of quantum mechanics - arguably our most powerfully predictive scientific theory to date - describes a branching Universe composed of an infinite number of quasi-classical macroscopic physical worlds. Though elegant in its straightforward rendering of the mechanics, the Many Worlds Interpretation presents a challenge for understanding identity over time. If we wish to preserve the notion of strict numerical identity, we are faced with the choice between: denying the transitivity of identity; very short-lived lives with near constant death; or accepting that the world is filled with many more individuals than we previously dreamed. In adopting a perdurantist account of identity over time, I argue for this last option. But questions remain about the relationship that branching individuals have to those from whom they’ve split. In this dissertation, I develop a novel account that I call Many Worlds Counterparts. This theory takes its inspiration from Lewis’s Counterpart Theory in offering a modal analysis of de re possibility, but avoids the major challenges that Lewis’s theory faces.
Abstract What does realism about the quantum state imply? What follows when quantum theory is applied without restriction, if need be, to the whole universe? These are the questions which are debated in this book. All the chapters start from the point of realism, and based on the need, or the aspiration, for a theory that unites micro- and macroworlds, at least in principle. But the further claim argued by some is that if you allow the Schrödinger equation unrestricted application, supposing the quantum state to be something physically real, then this universe is one of countlessly many others, constantly branching in time, all of which are real. The result is the many worlds theory, also known as the Everett interpretation of quantum mechanics. The contrary claim sees this picture of many worlds as in no sense inherent in quantum mechanics, even when the latter is allowed unrestricted scope and even given that the quantum state itself is something physically real. For this picture of branching worlds fails to make physical sense, let alone common sense, even on its own terms. The status of these worlds, what they are made of, is never adequately explained. Ordinary ideas about time and identity over time become hopelessly compromised. The concept of probability itself is brought into question. This picture of many branching worlds is inchoate, it is a vision, an error. There are realist alternatives to many worlds, some even that preserve the Schrödinger equation unchanged. Twenty chapters, accompanied by commentaries and discussions, examine these claims and counterclaims in depth. They focus first on the question of ontology, the existence of worlds, second on the interpretation of probability, and third on alternatives or additions to many worlds. The introduction offers a helpful guide to the arguments for the Everett interpretation, particularly as they have been formulated in the last two decades.
abstract: This thesis attempts to explain Everettian quantum mechanics from the ground up, such that those with little to no experience in quantum physics can understand it. First, we introduce the history of quantum theory, and some concepts that make up the framework of quantum physics. Through these concepts, we reveal why interpretations are necessary to map the quantum world onto our classical world. We then introduce the Copenhagen interpretation, and how many-worlds differs from it. From there, we dive into the concepts of entanglement and decoherence, explaining how worlds branch in an Everettian universe, and how an Everettian universe can appear as our classical observed world. From there, we attempt to answer common questions about many-worlds and discuss whether there are philosophical ramifications to believing such a theory. Finally, we look at whether the many-worlds interpretation can be proven, and why one might choose to believe it. (abstract)
Abstract This paper shall explore the conjunction of eternalism and Everettian quantum mechanics. It shall be argued that there is a strong analogy between these two views. In case there is an indefinite number of worlds and observers that are all equally real, there should be an indefinite number of local times which are all also equally real. Whereas Everettianism, specifically the diverging version, treats actuality indexically, relativistic eternalism treats tense indexically. All times exist analogously to all isolated Everettian worlds. There is no unique ‘now’ that cuts throughout all that physically exists. Instead, as eternalism propounds, all times exist. The paper concludes that eternalism and the many-worlds interpretation are not only compatible but complement each other, providing a coherent framework for understanding the nature of temporal reality.
The Many-worlds Interpretation (MWI) of quantum mechanics has captivated physicists and philosophers alike since its inception in the mid-20th century. This paper explores the historical roots, evolution, and implications of the MWI within the context of quantum theory. Beginning with an overview of early developments in quantum mechanics and the emergence of foundational interpretations, we delve into the origins of the MWI through the groundbreaking work of physicist Hugh Everett III. Everett's doctoral thesis proposed a radical solution to the measurement problem, positing the existence of multiple branching universes to account for quantum phenomenon. We trace the evolution of the MWI, examining its refinement and elaboration by subsequent physicists such as John Wheeler. Furthermore, we discuss the MWI's impact on contemporary physics, including its connections to quantum information theory and ongoing experimental tests. By providing a comprehensive analysis of the MWI's historical development and current relevance, this paper offers insights into one of the most provocative interpretations of quantum mechanics and its implications for our understanding of the universe.