15 found
Sort by:
See also:
Profile: John Byron Manchak (University of Washington)
  1. John Byron Manchak (forthcoming). Is Spacetime Hole-Free? General Relativity and Gravitation.
    Here, we examine hole-freeness - a condition sometimes imposed to rule out seemingly artificial spacetimes. We show that under existing definitions (and contrary to claims made in the literature) there exist inextendible, globally hyperbolic spacetimes which fail to be hole-free. We then propose an updated formulation of the condition which enables us to show the intended result. We conclude with a few general remarks on the strength of the definition and then formulate a precise question which may be interpreted as: (...)
    Direct download  
     
    My bibliography  
     
    Export citation  
  2. James Owen Weatherall & John Byron Manchak (forthcoming). The Geometry of Conventionality. 81 (2):233-247.
    There is a venerable position in the philosophy of space and time that holds that the geometry of spacetime is conventional, provided one is willing to postulate a “universal force field.” Here we ask a more focused question, inspired by this literature: in the context of our best classical theories of space and time, if one understands “force” in the standard way, can one accommodate different geometries by postulating a new force field? We argue that the answer depends on one’s (...)
    Direct download (2 more)  
     
    My bibliography  
     
    Export citation  
  3. John Byron Manchak (2012). Essay Review:Topics in the Foundations of General Relativity and Newtonian Gravitation TheoryDavid Malament , Topics in the Foundations of General Relativity and Newtonian Gravitation Theory . Chicago: University of Chicago Press (2012), Xii+349 Pp., $55.00 (Cloth). [REVIEW] Philosophy of Science 79 (4):575-583.
  4. John Byron Manchak (2012). Essay Review: Topics in the Foundations of General Relativity and Newtonian Gravitation Theory. Philosophy of Science 79 (4):575-583.
    Direct download  
     
    My bibliography  
     
    Export citation  
  5. Marc Lange, Raphael van Riel, Maximilian Schlosshauer, Gregory Wheeler, Zalán Gyenis, Miklós Rédei, John Byron Manchak, James Owen Weatherall, Bruce Glymour & Bradford Skow (2011). 10. Discussion: Problems for Natural Selection as a Mechanism Discussion: Problems for Natural Selection as a Mechanism (Pp. 512-523). [REVIEW] Philosophy of Science 78 (3).
     
    My bibliography  
     
    Export citation  
  6. John Byron Manchak (2011). No No-Go: A Remark on Time Machines. Studies in History and Philosophy of Science Part B 42 (1):74-76.
    We present a counterexample to Krasnikov's (2002) much discussed time machine no-go result. In addition, we prove a positive statement: a time machine existence theorem under a modest "no holes" assumption.
    Direct download (4 more)  
     
    My bibliography  
     
    Export citation  
  7. John Byron Manchak (2011). Time Travel: Why It May Not Pay to Work Out All the Kinks. Philosophy of Science 78 (5):1037-1045.
    Direct download (4 more)  
     
    My bibliography  
     
    Export citation  
  8. John Byron Manchak (2010). On the Possibility of Supertasks in General Relativity. Foundations of Physics 40 (3):276-288.
    Malament-Hogarth spacetimes are the sort of models within general relativity that seem to allow for the possibility of supertasks. There are various ways in which these spacetimes might be considered physically problematic. Here, we examine these criticisms and investigate the prospect of escaping them.
    Direct download (5 more)  
     
    My bibliography  
     
    Export citation  
  9. John Byron Manchak (2009). Can We Know the Global Structure of Spacetime? Studies in History and Philosophy of Modern Physics 40 (1):53-56.
    Here, we briefly review the notion of observational indistinguishability within the context of classical general relativity. We settle a conjecture given by Malament (1977) concerning the subject and then strengthen the result considerably. The upshot is this: There seems to be a robust sense in which the global structure of every cosmological model is underdetermined.
    Direct download (5 more)  
     
    My bibliography  
     
    Export citation  
  10. John Byron Manchak (2009). On Force in Cartesian Physics. Philosophy of Science 76 (3):295-306.
    There does not seem to be a consistent way to ground the concept of “force” in Cartesian first principles. In this article, I first review the literature on the subject. Then, I offer an alternative interpretation of force—one that seems to be coherent and consistent with Descartes’ project. Not only does the new position avoid the problems of previous interpretations, but it does so in such a way as to support and justify those previous interpretations. *Received June 2007; revised June (...)
    Direct download (6 more)  
     
    My bibliography  
     
    Export citation  
  11. John Byron Manchak (2009). On the Existence of “Time Machines” in General Relativity. Philosophy of Science 76 (5):1020-1026.
    Within the context of general relativity, we consider one definition of a “time machine” proposed by Earman, Smeenk, and Wüthrich. They conjecture that, under their definition, the class of time machine spacetimes is not empty. Here, we prove this conjecture. †To contact the author, please write to: Department of Philosophy, University of Washington, Box 353350, Seattle, WA 98195‐3350; e‐mail: manchak@uw.edu.
    Direct download (4 more)  
     
    My bibliography  
     
    Export citation  
  12. John Byron Manchak (2008). Is Prediction Possible in General Relativity? Foundations of Physics 38 (4):317-321.
    Here we briefly review the concept of "prediction" within the context of classical relativity theory. We prove a theorem asserting that one may predict one's own future only in a closed universe. We then question whether prediction is possible at all (even in closed universes). We note that interest in prediction has stemmed from considering the epistemological predicament of the observer. We argue that the definitions of prediction found thus far in the literature do not fully appreciate this predicament. We (...)
    Direct download (5 more)  
     
    My bibliography  
     
    Export citation  
  13. John Byron Manchak, “Time Travel” in Godel Spacetime: Why It Doesn't Pay to Work Out All the Kinks.
    Here we provide a proof that there exist closed timelike curves in Gödel spacetime with total acceleration less than 2π(9 + 6√3)^1/2. This answers a question posed by David Malament.
    Direct download  
     
    My bibliography  
     
    Export citation  
  14. John Byron Manchak, Observational Indistinguishability and Geodesic Incompleteness.
    It has been suggested by Clark Glymour that the spatio-temporal structure of the universe might be underdetermined by all observational data that could ever, theoretically, be gathered. It is possible for two spacetimes to be observationally indistinguishable (OI) yet topologically distinct. David Malament extended the argument for the underdetermination of spacetime structure by showing that under quite general conditions (such as the absence of any closed timelike curves) a spacetime will always have an OI counterpart (at least in weak sense). (...)
    Direct download  
     
    My bibliography  
     
    Export citation  
  15. John Byron Manchak, Self-Measurement and the Uncertainty Relations.
    Non-collapse theories of quantum mechanics have the peculiar characteristic that, although their measurements produce definite results, their state vectors remain in a superposition of possible outcomes. David Albert has used this fact to show that the standard uncertainty relations can be violated if self-measurements are made. Bradley Monton, however, has held that Albert has not been careful enough in his treatment of self-measurement and that being more careful (considering mental state supervenience) implies no violation of the relations. In this paper, (...)
    Direct download  
     
    My bibliography  
     
    Export citation