Synthese

, Volume 190, Issue 4, pp 619–637 | Cite as

How to evaluate counterfactuals in the quantum world

Open Access
Article

Abstract

In the article I discuss possible amendments and corrections to Lewis’s semantics for counterfactuals that are necessary in order to account for the indeterministic and non-local character of the quantum world. I argue that Lewis’s criteria of similarity between possible worlds produce incorrect valuations for alternate-outcome counterfactuals in the EPR case. Later I discuss an alternative semantics which rejects the notion of miraculous events and relies entirely on the comparison of the agreement with respect to individual facts. However, a controversy exists whether to include future indeterministic events in the criteria of similarity. J. Bennett has suggested that an indeterministic event count toward similarity only if it is a result of the same causal chain as in the actual world. I claim that a much better agreement with the demands of the quantum-mechanical indeterminism can be achieved when we stipulate that possible worlds which differ only with respect to indeterministic facts that take place after the antecedent-event should always be treated as equally similar to the actual world. In the article I analyze and dismiss some common-sense counterexamples to this claim. Finally, I critically evaluate Bennett’s proposal regarding the truth-conditions for true-antecedent counterfactuals.

Keywords

Counterfactuals Indeterminism Quantum mechanics True-antecedent counterfactuals 

References

  1. Bedford D., Stapp H. P. (1995) Bell’s theorem in an indeterministic universe. Synthese 102: 139–164CrossRefGoogle Scholar
  2. Bennett J. (1984) Counterfactuals and temporal direction. The Philosophical Review XCIII(1): 57–91Google Scholar
  3. Bennett J. (2003) A philosophical guide to conditionals. Clarendon Press, OxfordCrossRefGoogle Scholar
  4. Bigaj T. (2004) Counterfactuals and spatiotemporal events. Synthese 142(1): 1–20CrossRefGoogle Scholar
  5. Bigaj T. (2006) Non-locality and possible worlds: A counterfactual perspective on quantum entanglement. Ontos Verlag, FrankfurtGoogle Scholar
  6. Bigaj T. (2007) Counterfactuals and non-locality of quantum mechanics. Foundations of Science 12: 85–108CrossRefGoogle Scholar
  7. Clifton R., Redhead M., Butterfield J. (1990) Nonlocal influences and possible worlds. British Journal for the Philosophy of Science 41: 5–58CrossRefGoogle Scholar
  8. Dowe P. (2004) Causes are physically connected to their effects: Why preventers and omissions are not causes. In: Hitchcock C. (Ed.), Contemporary debates in philosophy of science. Blackwell, Oxford, pp 189–196Google Scholar
  9. Einstein A., Podolsky B., Rosen N. (1935) Can quantum-mechanical description of physical reality be considered complete?. Physical Review 48: 696–702CrossRefGoogle Scholar
  10. Elga A. (2001) Statistical mechanics and the asymmetry of counterfactual dependence. Philosophy of Science 68: S313–S324CrossRefGoogle Scholar
  11. Finkelstein J. (1999) Space–time counterfactuals. Synthese 119: 287–298CrossRefGoogle Scholar
  12. Ghirardi G., Grassi R. (1994) Outcome predictions and property attribution: The EPR argument reconsidered. Studies in the History and Philosophy of Science 25(3): 397–423CrossRefGoogle Scholar
  13. Greenberger D., Horne M., Shimony A., Zeilinger A. (1990) Bell’s theorem without inequalities. American Journal of Physics 58: 1131–1143CrossRefGoogle Scholar
  14. Griffiths R. B. (1999) Consistent quantum counterfactuals. Physical Review A 60(1): R5–R8CrossRefGoogle Scholar
  15. Griffiths R. B. (2001) Consistent quantum theory. Cambridge University Press, CambridgeCrossRefGoogle Scholar
  16. Hall N. (2000) Causation and the price of transitivity. The Journal of Philosophy 97(4): 198–222CrossRefGoogle Scholar
  17. Jackson F. (1977) A causal theory of counterfactuals. Australasian Journal of Philosophy 55: 3–21CrossRefGoogle Scholar
  18. Lewis D. (1973) Counterfactuals. Harvard University Press, Cambridge, MAGoogle Scholar
  19. Lewis, D. (Ed.) (1986). Counterfactual dependence and time’s arrow. In Philosophical papers (Vol. II). Oxford: Oxford University Press.Google Scholar
  20. McCall S. (1984) Counterfactuals based on real possible worlds. Nous 18: 463–477CrossRefGoogle Scholar
  21. Mermin D. (1998) Nonlocal character of quantum theory?. American Journal of Physics 66(10): 920–924CrossRefGoogle Scholar
  22. Müller T. (2002) Branching space–time, modal logic and the counterfactual conditional. In: Placek T., Butterfield J. (Eds.), Non-locality and modality. Kluwer, Dordrecht, pp 273–291CrossRefGoogle Scholar
  23. Percival P. (1999) A note on lewis on counterfactual dependence in a chancy world. Analysis 59(3): 165–173CrossRefGoogle Scholar
  24. Redhead M. (1987) Non-locality, incompleteness and realism. Oxford University Press, OxfordGoogle Scholar
  25. Schaffer J. (2004) Causes need not be physically connected to their effects: The case for negative causation. In: Hitchcock C. (Ed.), Contemporary debates in philosophy of science. Blackwell, Oxford, pp 197–216Google Scholar
  26. Shimony A., Stein H. (2001) Comment on ‘nonlocal character of quantum theory’ by Henry P Stapp. American Journal of Physics 69: 848–853CrossRefGoogle Scholar
  27. Stalnaker R. C. (1968) A theory of conditionals. In: Rescher N. (Ed.), Studies in logical theory. Blackwell, OxfordGoogle Scholar
  28. Stapp H. P. (1971) S-matrix Interpretation of quantum theory. Physical Review 3: 1303–1320Google Scholar
  29. Stapp H. P. (1989) Quantum nonlocality and the description of nature. In: Cushing J., McMullin E. (Eds.), Philosophical consequences of quantum theory reflections on Bell’s theorem. University of Notre Dame Press, Notre Dame, pp 154–174Google Scholar
  30. Stapp H. P. (1997) Nonlocal character of quantum theory. American Journal of Physics 65: 300–304CrossRefGoogle Scholar
  31. Stapp H. (1998) Meaning of Counterfactual Statements in Quantum Physics. American Journal of Physics 66(10): 924–926CrossRefGoogle Scholar
  32. Stapp, H. P. (2001). Bell’s theorem without hidden variables. Lawrence Berkeley Laboratory Report No. LBNL 46942, quant-ph/0010047.Google Scholar
  33. Vaidmann L. (1999) Defending time-symmetrized quantum counterfactuals. Studies in History and Philosophy of Modern Physics 30: 373–397CrossRefGoogle Scholar

Copyright information

© The Author(s) 2012

Authors and Affiliations

  1. 1.Institute of PhilosophyUniversity of WarsawWarsawPoland

Personalised recommendations