Abstract
I examine the epistemological debate on scientific realism in the context of quantum mechanics (QM), focusing on the empirical underdetermination of different formulations (and interpretations) of QM. This underdetermination is unsurprising in the light of the realism debate, since much of the interpretational, metaphysical work on QM transcends those epistemic commitments of realism that cohere well with the history of science. I sketch a way of demarcating empirically idle metaphysics of QM from the empirically well-confirmed aspects of the theory in a way that withholds realist commitment to what quantum state |Ψ> represents. I argue that such commitment is not required for fulfilling the ultimate realist motivation: accounting for the empirical success of QM in a way that is in tune with a broader understanding of how theoretical science progresses and latches onto reality.
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Notes
- 1.
The realist intuition about quantum mechanics is driven by countless novel predictions and explanatory achievements with respect to various distinct phenomena regarding atomic spectra, the periodic structure of elements, and the band structure of the semiconductors, to name a few.
- 2.
- 3.
This lack of consensus is equally true amongst philosophers of physics and physicists themselves. For one snapshot, see Schlosshauer et al. (2013).
- 4.
- 5.
Note that none of this speaks against the rationality, meaningfulness, or purposefulness of these metaphysical ideas. The point is purely epistemological.
- 6.
Peter Lewis (2016: 182) aptly summarises the state of play at the end of his book length review of quantum metaphysics: “Very little can be concluded unconditionally on the basis of quantum mechanics . . . The best we can say is that not everything in our received classical worldview can be right.”
- 7.
- 8.
Ehrenfest’s theorem shows how quantum mechanical expectation values of momentum and position operators obey an equation that structurally corresponds to Newton’s equations.
- 9.
French (2014) furthermore takes the continuity and enrichment of the theories’ symmetry features to signal the need to shift from (merely) epistemic structural realism (ESR) to ontological structural realism (OSR):
But if ESR is going to [incorporate the kinds of structures that matter in QM, such as the structures encoding permutation symmetry], then it will have to take on the metaphysical consequences of this symmetry and those, I argue, lead us to abandon the notion of object, hidden or otherwise. In other words, if structural realism is to broaden its grasp and seize the kinds of structures that modern physics actually presents to us, then it is going to have to shift from ESR to OSR. (p. 19)
As far as the scientific realism debate in general philosophy of science is concerned, this shift is in tension with the epistemological motivations that led to the idea of structural realism in the first place. The degree of epistemic humility that Worrall recommended by placing the realist’s commitment to mere structure (as opposed to ‘nature’) is quite drastic from the point of view of ‘standard’ realism. If we take this degree of humility to be epistemically well motivated in the first place, and if we think that the distinction between structure and nature can be sensibly drawn, then we should see it as indicating scientists’ unreliability in theorising about the nature of light and the nature of all other things (ultimately) quantum mechanical. But this level of scepticism about scientists’ reliability to theorise about the fundamental nature of the world would also, it seems, speak against the philosopher’s reliability to figure out whether the structural features of our best theories correspond to a structuralist ontology or otherwise (see also Saatsi 2007).
- 10.
Ontic structural realism is a clear exception to this, but for the reasons given (cf. footnote 10) I will here focus on structural realism merely as a form of epistemic humility.
- 11.
Musgrave (1992) argues that a realist can appeal to general metaphysical criteria to eliminate all but one competing interpretation. In the light of the anti-metaphysical trend in the contemporary realism debate such general metaphysical criteria for theory-choice are difficult to motivate as a reliable source of justification, however.
- 12.
This is of course not to say that such work cannot become responsible for such successes, but this potential has no bearing on our current epistemic commitments.
- 13.
As Schaffer (2017, p. 2) explains:
With causal explanation, there is the structure of cause (such as the rock striking the window), law (laws of nature), and effect (such as the shattering of the window). Metaphysical explanation has a parallel structure, involving ground (the more fundamental source), principle (metaphysical principles of grounding), and grounded (the less fundamental result). One finds a similar structure with logical explanation, involving premise, inference rule, and conclusion.
- 14.
Wallace (2019) argues against philosophers’ commonplace idea that collapse (or ‘projection’) postulate is central to ‘orthodox’ or ‘standard’ QM that physicists employ in practical applications.
References
Allori, V. (2013). Primitive ontology and the structure of fundamental physical theories. In D. Z. Albert & A. Ney (Eds.), The wave function: Essays in the metaphysics of quantum mechanics (pp. 58–75). Oxford: Oxford University Press.
Barrett, J. A. (2003). Are our best physical theories (probably and/or approximately) true. Philosophy of Science, 70(5), 1206–1218.
Barrett, J. A. (2008). Approximate truth and descriptive nesting. Erkenntnis, 68(2), 213–224.
Belousek, D. W. (2005). Underdetermination, realism, and theory appraisal: An epistemological reflection on quantum mechanics. Foundations of Physics, 35(4), 669–695.
Bhogal, H., & Perry, Z. (2015). What the humean should say about entanglement: What the humean should say about entanglement. Noûs, 1–21.
Bigelow, J., & Pargetter, R. (1990). Science and necessity. Cambridge: Cambridge University Press.
Bokulich, A. (2016). Fiction as a vehicle for truth: Moving beyond the ontic conception. The Monist, 99(3), 260–279.
Brown, H., Elby, A., & Weingard, R. (1996). Cause and effect in the pilotwave interpretation of quantum mechanics. In J. T. Cushing et al. (Eds.), Bohmian mechanics and quantum theory: An appraisal (pp. 309–319). Dordrecht: Kluwer.
Cartwright, N. (1983). How the laws of physics lie. Oxford: Oxford University Press.
Chakravartty, A. (1998). Semirealism. Studies in History and Philosophy of Science Part A, 29, 391–408.
Chakravartty, A. (2007). A metaphysics for scientific realism: Knowing the unobservable. Cambridge: Cambridge University Press.
Cohen, J., & Callender, C. (2009). A better best system account of lawhood. Philosophical Studies, 145(1), 1–34.
Colyvan, M. (2015). Indispensability arguments in the philosophy of mathematics. Stanford Encyclopedia of Philosophy.
Cordero, A. (2001). Realism and underdetermination: Some clues from the practices-up. Philosophy of Science, 68, S301–S312.
Cushing, J. T. (1994). Quantum mechanics: Historical contingency and the Copenhagen hegemony. Chicago: University of Chicago Press.
Egg, M. (2012). Causal warrant for realism about particle physics. Journal of General Philosophy of Science, 43(2), 259–280.
Egg, M. (2016). Expanding our grasp: Causal knowledge and the problem of unconceived alternatives. British Journal for the Philosophy of Science, 67(1), 115–141.
Ellis, B. (2009). Metaphysics of scientific realism. London: Acumen.
Esfeld, M. (2014). The primitive ontology of quantum physics: Guidelines for an assessment of the proposals. Studies in History and Philosophy of Modern Physics, 47, 99–106.
Esfeld, M., Lazarovici, D., Lam, V., & Hubert, M. (2017). The physics and metaphysics of primitive stuff. The British Journal for the Philosophy of Science, 68, 133–161.
French, S. (2014). The structure of the world: Metaphysics and representation. Oxford: Oxford University Press.
French, S., & Saatsi, J. (2018). Symmetries and explanatory dependencies in physics. In A. Reutlinger & J. Saatsi (Eds.), Explanation beyond causation: Philosophical perspectives on non-causal explanations. Oxford: Oxford University Press.
Frigg, R., & Votsis, I. (2011). Everything you always wanted to know about structural realism but were afraid to ask. European Journal of Philosophy of Science, 1(2), 227–276.
Hacking, I. (1982). Experimentation and scientific realism. Philosophical Topics, 13, 71–87.
Hacking, I. (1983). Representing and intervening: Introductory topics in the philosophy of natural science. Cambridge: Cambridge University Press.
Healey, R. (2015). How quantum theory helps us explain. The British Journal for the Philosophy of Science, 66, 1–43.
Jansson, L., & Saatsi, J. (2018). Explanatory abstractions. British Journal for the Philosophy of Science. Advance Access. axy026.
Ladyman, J., & Ross, D. (2007). Everything must go: Metaphysics naturalised. Oxford: Oxford University Press.
Landsman, N. P. (2007). Between classical and quantum. In J. Butterfield & J. Earman (Eds.), Handbook of the philosophy of science: Philosophy of physics (pp. 417–554). Amsterdam: Elsevier.
Laudan, L. (1981). A confutation of convergent realism. Philosophy of Science, 48(1), 19–49.
Lewis, D. (1986). On the plurality of worlds. Oxford: Basil Blackwell.
Lewis, P. (2016). Quantum ontology: A guide to the metaphysics of quantum mechanics. Oxford: Oxford University Press.
Maudlin, T. W. (2007). Completeness, supervenience and ontology. Journal of Physics A: Mathematical and Theoretical, 40(12), 3151.
Maudlin, T. (2010). Can the world be only wavefunction? In S. Saunders, J. Barrett, A. Kent, & D. Wallace (Eds.), Many worlds? Everett, quantum theory, & reality (pp. 121–143). Oxford: Oxford University Press.
Morrison, M. (2007). Spin: All is not what it seems. Studies in History and Philosophy of Modern Physics, 38(3), 529–557.
Musgrave, A. (1992). Realism about what. Philosophy of Science, 59(4), 691–697.
Musgrave, A. (1996). Realism, truth and objectivity. In R. Cohen, R. Hilpinen, & Q. Renzong (Eds.), Realism and anti-realism in the philosophy of science (pp. 19–44). Dordrecht: Kluwer.
Ney, A., & Albert, D. Z. (2013). The wave function: Essays on the metaphysics of quantum mechanics. Oxford: Oxford University Press.
Norsen, T. (2014). The pilot-wave perspective on spin. American Journal of Physics, 82, 337–348.
Putnam, H. (1975). Philosophical papers: Volume 2, mind, language and reality (Vol. Volume 2). Cambridge: Cambridge University Press.
Rosaler, J. (2016). Interpretation neutrality in the classical domain of quantum theory. Studies in History and Philosophy of Modern Physics, 53, 54–72.
Saatsi, J. (2007). Living in harmony: Nominalism and the explanationist argument for realism. International Studies in the Philosophy of Science, 21(1), 19–33.
Saatsi, J. (2015a). Historical inductions, old and new. Synthese. First Online: doi:https://doi.org/10.1007/s11229-015-0855-5.
Saatsi, J. (2015b). Replacing recipe realism. Synthese, 194(9), 3233–3244.
Saatsi, J. (2016). What is theoretical progress of science. Synthese, First Online.
Saatsi, J. (2017a). Dynamical systems theory and explanatory indispensability. Philosophy of Science, 84(5), 892–904.
Saatsi, J. (2017b). Explanation and explanationism in science and metaphysics. In M. Slater & Z. Yudell (Eds.), Metaphysics and the philosophy of science: New essays (pp. 162–191). Oxford: Oxford University Press.
Saunders, S., Barrett, J., Kent, A., & Wallace, D. (Eds.). (2010). Many worlds? Everett, quantum theory, & reality. Oxford: Oxford University Press.
Schaffer, J. (2017). The ground between the gaps. Philosophers’ Imprint, 17(11), 1–26.
Schlosshauer, M. (2007). Decoherence and the quantum-to-classical transition. Berlin: Springer.
Schlosshauer, M., Kofler, J., & Zeilinger, A. (2013). A snapshot of foundational attitudes toward quantum mechanics. Studies in History and Philosophy of Modern Physics, 44(3), 222–230.
Stanford, P. K. (2006). Exceeding Our Grasp: Science, History, and the Problem of Unconceived Alternatives. Oxford: Oxford University Press.
Stanford, P. K. (2015). “Atoms exist” is probably true, and other facts that should not comfort scientific realists. Journal of Philosophy, 112(8), 397–416.
Timothy, W. (2016). Modal science. Canadian Journal of Philosophy, 46(4–5), 453–492.
Vaidman, L. (2014). Many-worlds interpretation of quantum mechanics. Stanford Encyclopedia of Philosophy.
van Fraassen, B. C. (1980). The Scientific Image. New York: Oxford University Press.
van Fraassen, B. C. (1991). Quantum Mechanics: An Empiricist View. Oxford: Oxford University Press.
Wallace, D. (2012a). Decoherence and its role in the modern measurement problem. Philosophical Transactions of the Royal Society A, 370(1975), 4576–4593.
Wallace, D. (2012b). The Emergent Multiverse: Quantum Theory according to the Everett Interpretation. Oxford: Oxford University Press.
Wallace, D. (2019). What is orthodox quantum mechanics? This volume.
Woodward, J. (2003a). Experimentation, causal inference, and instrumental realism. In H. Radder (Ed.), The Philosophy of Scientific Experimentation (pp. 87–118). Pittsburgh: University of Pittsburgh Press.
Woodward, J. (2003b). Making things happen: A causal theory of explanation. Oxford: Oxford University Press.
Worrall, J. (1989). Structural realism: The best of both worlds? Dialectica, 43, 99–124.
Acknowledgments
Support from Arts and Humanities Research Council (as part of Scientific Realism and the Quantum project) is gratefully acknowledged. I received helpful feedback on presentations in Leeds, San Sebastian, NYU Abu Dhabi. Special thanks to Fabio Ceravolo, Kevin Coffey, Steven French, Simon Newey, Kohei Morita for helpful discussions.
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Saatsi, J. (2019). Scientific Realism Meets Metaphysics of Quantum Mechanics. In: Cordero, A. (eds) Philosophers Look at Quantum Mechanics. Synthese Library, vol 406. Springer, Cham. https://doi.org/10.1007/978-3-030-15659-6_10
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