ONTOLOGY OF FUNDAMENTAL PHYSICS
Workshop in Philosophy of Physics
Instituto de Filosofía y Ciencias de la Complejidad (IFICC), Santiago, Chile
December 9, 2015
IDEA AND MOTIVATION
Fundamental physics aims to account for the behavior of nature. Yet, notwithstanding the empirical success of our best physical theories, there remain outstanding philosophical questions about their own foundations. In particular, the jury is still out concerning what are the basic constituents of matter. For instance, there is an ongoing debate about the ontology of Quantum Field Theory, in that it lends itself to either a particle or a field interpretation. Moreover, philosophers of physics disagree on what sort of realism, if any, one should adopt when trying to understand what physics tells us about the world. This workshops explores a number of open problems about the ontology of some of our most successful physical theories.
|Giovanni Valente is an assistant professor of philosophy at the University of Pittsburgh, where he is also a fellow in the Center for Philosophy of Science. He gained his PhD in History and Philosophy of Science from the University of Maryland in 2009. His research interests include the philosophy of physics and the philosophy of science. Currently, the main focus of his work is on quantum field theory and statistical mechanics. After several publications on those topics, he received, in 2014, the Cushing Prize in History and Philosophy of Physics. For more information visit his website: giovannivalente.weebly.com|
|James Owen Weatherall is an associate professor of logic and philosophy of science at the University of California, Irvine, where he is also a member of the Institute for Mathematical Behavioral Science. He gained his first PhD in Mathematics and Physics from the Stevens Institute of Technology in 2009. In 2012, he earned his second PhD in Philosophy of Science from the University of California. Most of his recent work has been on the mathematical and conceptual foundations of classical and quantum field theories. But he also works on issues in general philosophy of science, with particular interest in questions concerning model building in finance. He is the author of the book The Physics of Wall Street (2013), which explains how ideas have moved from physics into financial modeling over the last century. For more information visit his website: http://jamesowenweatherall.com/|
Diego Romero Maltrana is an associate Professor of Physics at the Pontificia Universidad Católica de Valparaíso and he is a member of the Instituto de Filosofía y Ciencias de la Complejidad (IFICC). He earned his PhD in Physics from the Pontificia Universidad Católica de Chile. He also obtained an MSc in Philosophy of Physics from the University of Oxford. His recent work in philosophy of physics includes the analysis of the equivalence of mass and energy proposed by Albert Einstein, the Higgs boson and the relation between symmetries and conserved quantities. For more information visit his website: http://ificc.cl/content/diego-romero-matrana
Restoring Particle Phenomenology in Quantum Field Theory
Giovanni Valente (University of Pittsburgh)
No-go theorems are known in the literature to the effect that, in relativistic quantum field theory, particle localizability in the strict sense violates relativistic causality. In order to account for particle phenomenology without particle ontology, Halvorson and Clifton (2002) proposed an approximate localization scheme. In a recent paper, Arageorgis and Stergiou (2013) proved a no-go result that suggests that, even within such a scheme, there would arise act-outcome correlations over the entire spacetime, thereby violating relativistic causality. In this talk, I show that this conclusion is untenable. In particular, I argue that one can recover particle phenomenology without having to give up relativistic causality.
On Stuff: The Field Concept in Classical and Quantum Physics
James Owen Weatherall (University of California, Irvine)
Discussions of physical “ontology” often come down to two basic options. Either the basic physical entities areparticles, or else they are fields. (A third option, not for the faint of heart, is to accept some combination of the two.) I will argue that, in fact, it is not at all clear what it would mean to say that the world consists of fields. Speaking classically (i.e., non-quantum-ly), there are many different sorts of thing that go by the name “field”, each with different representational roles. Even among those that have some claim to being “fundamental” in the appropriate sense, it does not seem that a single interpretational strategy could apply in all cases. I will end by suggesting that standard strategies for constructing quantumtheories of fields are not sufficiently sensitive to the different roles that “fields” can play in classical physics. Along the way, I will say something about an old debate in the foundations of relativity theory, concerning whether the spacetime metric is a “geometrical” or “physical” field. The view I will defend is that the metric is much like the electromagnetic field: geometrical!
Symmetries, Conserved Quantities and Ontological Priority, a Study Case for Structural Realism
Diego Romero Maltrana (Universidad Católica de Valparaiso/IFICC)
Structural Realism is, for many, our best theoretical account of science. A theory dealing with ‘what science is’ not necessarily must have a say on the nature of the ‘objects studied by’ science, however, some varieties of Structural Realism do have deep consequences on our conceptions on this regard. The analysis of the ontological priority of conserved quantities over symmetries is used here to highlight some difficulties associated to those varieties of Structural Realism.