•  10
    Pilot-Wave Theory Without Nonlocality
    Foundations of Physics 52 (5): 1-15. 2022.
    It’s generally taken to be established that no local hidden-variable theory is possible. That conclusion applies if our world is a _thread_, where a thread is a world where particles follow trajectories, as in Pilot-Wave theory. But if our world is taken to be a _set_ of threads locality can be recovered. Our world can be described by a _many-threads_ theory, as defined by Jeffrey Barrett in the opening quote. Particles don’t follow trajectories because a particle in our world is a set of _eleme…Read more
  •  33
    Proposed derivations of the Born rule for Everettian theory are controversial. I argue that they are unnecessary but may provide justification for a simplified version of the Principal Principle. It’s also unnecessary to replace Everett’s idea that a subject splits in measurement contexts with the idea that subjects have linear histories which partition Many worlds? Everett, quantum theory, and reality, Oxford University Press, Oxford, pp 181–205, 2010; Wallace in The emergent multiverse, Oxford…Read more
  •  25
    It is widely believed that the semantic contents of some linguistic and mental representations are determined by factors independent of a person’s bodily makeup. Arguments derived from Hilary Putnam’s seminal Twin Earth thought experiment have been especially influential in establishing that belief. I claim that there is a neglected version of the mind-body relation which undermines those arguments and also excludes the possibility of zombies. It has been neglected because it is counterintuitive…Read more
  •  104
    I continue to maintain that David Lewis’s concept of overlapping persons cannot yield pre-measurement uncertainty in the Everett interpretation of quantum mechanics in the way that Simon Saunders and David Wallace originally seemed to suggest. However, I argue that in their reply to me they make it clear that they do not wish to invoke overlap of persons after all. That makes it mysterious why they defended their interpretation of personal overlap in the first place and questionable what role ov…Read more
  •  49
    The roundsquare copula: A semantic internalist's rejoinder
    Proceedings of the Aristotelian Society 96 (1): 395-400. 1996.
    Paul Tappenden; The Roundsquare Copula: A Semantic Internalist's Rejoinder, Proceedings of the Aristotelian Society, Volume 96, Issue 1, 1 June 1996, Pages 395–
  •  329
    Evidence and Uncertainty in Everett’s Multiverse
    British Journal for the Philosophy of Science 62 (1): 99-123. 2011.
    How does it come about then, that great scientists such as Einstein, Schrödinger and De Broglie are nevertheless dissatisfied with the situation? Of course, all these objections are levelled not against the correctness of the formulae, but against their interpretation. [...] The lesson to be learned from what I have told of the origin of quantum mechanics is that probable refinements of mathematical methods will not suffice to produce a satisfactory theory, but that somewhere in our doctrine is …Read more
  •  37
    Objective probability and the mind-body relation
    Studies in History and Philosophy of Science Part B: Studies in History and Philosophy of Modern Physics 57 8-16. 2017.
    Objective probability in quantum mechanics is often thought to involve a stochastic process whereby an actual future is selected from a range of possibilities. Everett’s seminal idea is that all possible definite futures on the pointer basis exist as components of a macroscopic linear superposition. I demonstrate that these two conceptions of what is involved in quantum processes are linked via two alternative interpretations of the mind-body relation. This leads to a fission, rather than diverg…Read more
  •  145
    Saunders and Wallace on Everett and Lewis
    British Journal for the Philosophy of Science 59 (3): 307-314. 2008.
    Simon Saunders and David Wallace attempt to use a modified form of David Lewis's analysis of personal fission to ground the claim that prior to undergoing Everett branching an informed subject can be uncertain about which outcome s/he will observe. I argue that a central assumption of this seductive idea is questionable despite appearing innocuous and that at the very least further argument is needed in support of it. CiteULike    Connotea    Del.icio.us    What's this?
  •  51
    Identity and probability in Everett's multiverse
    British Journal for the Philosophy of Science 51 (1): 99-114. 2000.
    There are currently several versions of Everett's relative state interpretation of quantum mechanics, responding to a number of perceived problems for the original proposal. One of those problems is whether Everett's idea is in accord with the standard 'probabilistic' interpretation implicit in the Born rule. I argue in defence of what appears to be Everett's original view on this. The contribution I aim to make is a more complete discussion of the central issues of the identity of objects and o…Read more
  •  37
    In the current debate on the concept of probability in the Everett interpretation of quantum mechanics Saunders and Wallace argue for a notion of pre-measurement uncertainty whilst Greaves and Myrvold attempt to do without uncertainty altogether. Both these approaches are controversial and I suggest a middle way. I develop in detail an argument which Wallace has hinted at and Greaves has seen as beside the point in order to show that Vaidman’s concept of post-measurement uncertainty has more rel…Read more
  •  37
    Murray Gell-Mann and James Hartle have made an original proposal for a version of decoherent histories quantum mechanics which is specifically tailored so as not to imply the emergence of multiple quasi-classical worlds. I argue that there is an explanatory gap in the proposal but that there remains an important insight which might be used to tackle what can be seen as an outstanding problem for Hugh Everett III’s “relative state” interpretation of quantum mechanics, if it is understood as givin…Read more
  •  125
    A Metaphysics for Semantic Internalism
    Metaphysica 12 (2): 125-136. 2011.
    The contemporary popularity of semantic externalism has arisen from so-called Twin Earth thought experiments which suggest that the representational content of a natural kind term cannot be wholly determined by processes within a speaker's body. Such arguments depend on the intuition that the extensions of natural kind terms cannot have changed as the result of the scientific investigation of natural kinds' constitutions. I demonstrate that this externalist intuition depends on an assumption abo…Read more
  •  139
    Expectancy and rational action prior to personal fission
    Philosophical Studies 153 (2): 299-306. 2011.
    According to Sider’s stage theory a subject about to undergo personal fission should expect to experience each outcome simultaneously as distinct persons. How is the subject to make sense of this ? I argue that their most paradigmatically self-interested future-directed behaviour, betting for personal gain, ought to be exactly the same as in equivalent games of chance where the possible outcomes correspond to the fission output branches. So this novel form of expectancy, albeit strange, can be a…Read more
  •  119
    Expectancy and rational action prior to personal fission
    Philosophical Studies 153 (2). 2011.
    Some analyses of personal fission suggest that an informed subject should expect to have a distinct experience of each outcome simultaneously. Is rational provision for the future possible in such unfamiliar circumstances? I argue that, with some qualification, the subject can reasonably act as if faced with alternative possible outcomes with precise probabilities rather than multiple actual outcomes