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48Quantum spacetime: What do we know?In Craig Callender & Nicholas Huggett (eds.), Physics meets philosophy at the planck scale, . pp. 101--22This is a contribution to a book on quantum gravity and philosophy. I discuss nature and origin of the problem of quantum gravity. I examine the knowledge that may guide us in addressing this problem, and the reliability of such knowledge. In particular, I discuss the subtle modification of the notions of space and time engendered by general relativity, and how these might merge into quantum theory. I also present some reflections on methodological questions, and on some general issues in philos…Read more
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274Physics Needs Philosophy. Philosophy Needs PhysicsFoundations of Physics 48 (5): 481-491. 2018.Contrary to claims about the irrelevance of philosophy for science, I argue that philosophy has had, and still has, far more influence on physics than is commonly assumed. I maintain that the current anti-philosophical ideology has had damaging effects on the fertility of science. I also suggest that recent important empirical results, such as the detection of the Higgs particle and gravitational waves, and the failure to detect supersymmetry where many expected to find it, question the validity…Read more
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79Quantum GravityCambridge University Press. 2007.Quantum gravity poses the problem of merging quantum mechanics and general relativity, the two great conceptual revolutions in the physics of the twentieth century. The loop and spinfoam approach, presented in this book, is one of the leading research programs in the field. The first part of the book discusses the reformulation of the basis of classical and quantum Hamiltonian physics required by general relativity. The second part covers the basic technical research directions. Appendices inclu…Read more
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56Michelangelo’s stone: an argument against platonism in mathematicsEuropean Journal for Philosophy of Science 7 (2): 285-297. 2017.If there is a ‘platonic world’ \ of mathematical facts, what does \ contain precisely? I observe that if \ is too large, it is uninteresting, because the value is in the selection, not in the totality; if it is smaller and interesting, it is not independent of us. Both alternatives challenge mathematical platonism. I suggest that the universality of our mathematics may be a prejudice and illustrate contingent aspects of classical geometry, arithmetic and linear algebra, making the case that what…Read more
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39Notions like meaning, signal, intentionality, are difficult to relate to a physical word. I study a purely physical definition of "meaningful information", from which these notions can be derived. It is inspired by a model recently illustrated by Kolchinsky and Wolpert, and improves on Dretske classic work on the relation between knowledge and information. I discuss what makes a physical process into a signal.
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186Neither Presentism nor EternalismFoundations of Physics 49 (12): 1325-1335. 2019.Is reality three-dimensional and becoming real (Presentism), or is reality four-dimensional and becoming illusory (Eternalism)? Both options raise difficulties. I argue that we do not need to be trapped by this dilemma. There is a third possibility: reality has a more complex temporal structure than either of these two naive options. Fundamental becoming is real, but local and unoriented. A notion of present is well defined, but only locally and in the context of approximations.
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50Heisenberg mechanics is the good mechanicsIn Abhay Ashtekar & John Stachel (eds.), Conceptual Problems of Quantum Gravity, Birkhauser. pp. 2--126. 1991.
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67We observe entropy decrease towards the past. Does this imply that in the past the world was in a non-generic microstate? I point out an alternative. The subsystem to which we belong interacts with the universe via a relatively small number of quantities, which define a coarse graining. Entropy happens to depends on coarse-graining. Therefore the entropy we ascribe to the universe depends on the peculiar coupling between us and the rest of the universe. Low past entropy may be due to the fact th…Read more
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2Is there incompatibility between the ways time is treated in general relativity and in standard quantum mechanicsIn Abhay Ashtekar & John Stachel (eds.), Conceptual Problems of Quantum Gravity, Birkhauser. pp. 126--140. 1991.
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212Halfway through the Woods: Contemporary research on space and timeIn John Earman & John D. Norton (eds.), The Cosmos of Science: Essays of Exploration, University of Pittsburgh Press. pp. 180--223. 1997.
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119“Incerto Tempore, Incertisque Loci”: Can We Compute the Exact Time at Which a Quantum Measurement Happens? (review)Foundations of Physics 28 (7): 1031-1043. 1998.Without addressing the measurement problem (i. e., what causes the wave function to “collapse,” or to ”branch,” or a history to become realized, or a property to actualize), I discuss the problem of the timing of the quantum measurement: Assuming that in an appropriate sense a measurement happens, when precisely does it happen? This question can be posed within most interpretations of quantum mechanics. By introducing the operator M, which measures whether or not the quantum measurement has happ…Read more
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26Rohrlich claims that ``the problem of the arrow of time in classical dynamics has been solved". The solution he proposes is based on the equations governing the motion of extended particles. Rohrlich claims that these equations, which must take self-interaction into account, are are not invariant under time reversal. I dispute this claim, on several grounds.
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100Che cos'è la scienza: la rivoluzione di AnassimandroMondadori università. 2011.All human civilizations have thought that the world was made of sky above and the Earth below. All except one. For the Greeks, the Earth was a rock floating in space, and under the earth there was no ground, no turtles, nor the gigantic columns of which the Bible speaks. How did the Greeks understand that the Earth is suspended in nothingness? Who understood this and how? It is this unique "scientific revolution" of Anaximander of which the author speaks, which Karl Popper called "one of the mos…Read more
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Group Quantization of the Barbour-Bertotti ModelIn Abhay Ashtekar & John Stachel (eds.), Conceptual Problems of Quantum Gravity, Birkhauser. pp. 2--292. 1991.
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64Comment on: “Causality and the arrow of classical time”, by Fritz RohrlichStudies in History and Philosophy of Science Part B: Studies in History and Philosophy of Modern Physics 35 (3): 397-405. 2004.Rohrlich claims that “the problem of the arrow of time in classical dynamics has been solved”. The solution he proposes is based on the equations governing the motion of extended particles. Rohrlich claims that these equations, which must take self-interaction into account, are not invariant under time reversal. I dispute this claim, on several grounds.
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308“Forget time”: Essay written for the FQXi contest on the Nature of TimeFoundations of Physics 41 (9): 1475-1490. 2011.Following a line of research that I have developed for several years, I argue that the best strategy for understanding quantum gravity is to build a picture of the physical world where the notion of time plays no role at all. I summarize here this point of view, explaining why I think that in a fundamental description of nature we must “forget time”, and how this can be done in the classical and in the quantum theory. The idea is to develop a formalism that treats dependent and independent varia…Read more
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47Comment on: “Causality and the arrow of classical time”, by Fritz RohrlichStudies in History and Philosophy of Science Part B: Studies in History and Philosophy of Modern Physics 35 (3): 397-405. 2004.
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90I show that Aristotelian physics is a correct approximation of Newtonian physics in its appropriate domain, in the same precise sense in which Newton theory is an approximation of Einstein's theory. Aristotelian physics lasted long not because it became dogma, but because it is a very good theory.
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158Aristotle’s Physics: A Physicist’s LookJournal of the American Philosophical Association 1 (1): 23--40. 2015.ABSTRACT ABSTRACT: I show that Aristotelian physics is a correct and nonintuitive approximation of Newtonian physics in the suitable domain in the same technical sense in which Newton’s theory is an approximation of Einstein’s theory. Aristotelian physics lasted long not because it became dogma, but because it is a very good, empirically grounded theory. This observation suggests some general considerations on intertheoretical relationships
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98A Critical Look at StringsFoundations of Physics 43 (1): 8-20. 2013.Following the invitation of the editors of Foundations of Physics, I give here a personal assessment of string theory, from the point of view of an outsider, and I compare it with the theory, methods, and expectations of my own field
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79The Notion of Locality in Relational Quantum MechanicsFoundations of Physics 49 (2): 96-106. 2019.The term ‘locality’ is used in different contexts with different meanings. There have been claims that relational quantum mechanics is local, but it is not clear then how it accounts for the effects that go under the usual name of quantum non-locality. The present article shows that the failure of ‘locality’ in the sense of Bell, once interpreted in the relational framework, reduces to the existence of a common cause in an indeterministic context. In particular, there is no need to appeal to a m…Read more
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89An Argument Against the Realistic Interpretation of the Wave FunctionFoundations of Physics 46 (10): 1229-1237. 2016.Testable predictions of quantum mechanics are invariant under time reversal. But the evolution of the quantum state in time is not so, neither in the collapse nor in the no-collapse interpretations of the theory. This is a fact that challenges any realistic interpretation of the quantum state. On the other hand, this fact raises no difficulty if we interpret the quantum state as a mere calculation device, bookkeeping past real quantum events.
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29Cristina Bicchieri and Carlo Rovelli. Evolution and Revolution: The Dynamics of Corruption
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Perimeter InstituteDistinguished Visiting Research Chair
London, Ontario, Canada
Areas of Specialization
Philosophy of Physical Science |
Areas of Interest
Philosophy of Physical Science |
Metaphysics and Epistemology |