Abstract
Ever since the early days of quantum mechanics it has been suggested that consciousness could be linked to the collapse of the wave function. However, no detailed account of such an interplay is usually provided. In this paper we present an objective collapse model (a variation of the Continuous Spontaneous Location model) where the collapse operator depends on integrated information, which has been argued to measure consciousness. By doing so, we construct an empirically adequate scheme in which superpositions of conscious states are dynamically suppressed. Unlike other proposals in which “consciousness causes the collapse of the wave function,” our model is fully consistent with a materialistic view of the world and does not require the postulation of entities suspicious of laying outside of the quantum realm.
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Notes
The standard theory not only does not specify when a measurement happens, it also does not prescribe what it is that is being measured (i.e., in which basis will the collapse occur).
We use the term ‘cause’ in a rather loose way just to honour the traditional motto of the idea that the collapse of the wave function depends somehow on consciousness. In our work there is no commitment whatsoever with the claim that there is such a thing as causation at the fundamental level [see Price and Corry (eds.) (2007) for a discussion].
Decoherence studies the consequences of the inevitable interaction between a quantum system and its macroscopic environment.
A more serious complication regarding collapse models arises from the fact that they lead systems to states which are very close to eigenstates of the collapse operator, but not exactly to such eigenstates. Therefore, if one subscribes to the EE link, systems under collapse dynamics never actually possess well-defined values for properties associated with the collapse operator (nor for most other properties). The solution, then, is to substitute the EE link by something else. One alternative is the, so-called, fuzzy link interpretation introduced in Albert and Loewer (1996), in which one allows for some tolerance away from an eigenstate while ascribing the possession of well-defined properties. Another alternative is to construct out of the wave function a, so-called, primitive ontology, such as mass density or flashes, and to interpret such an entity as the three-dimensional stuff that populates the world [see Allori (2015)]. It is fair to say, though, that these approaches, while promising, still have some open issues to address [see, e.g., McQueen (2015)].
In its latest formulation, what has been called IIT 3.0, the proponents of IIT depart slightly from Shannon’s notion of information, which they call ‘extrinsic information,’ and focus in what they call ‘intrinsic information.’
Calculating \(\Phi ^{Max}\) might very well be beyond our cognitive capacities. However, for current purposes, the only thing required is that, for every state of a system, there is a well-defined value of \(\Phi ^{Max}\), independently of our capacity to come to know it.
The model that we present is consistent with different metaphysical views regarding the details of the relation between maximally integrated information and consciousness. For example, one might endorse something along the lines of IIT and think, as a referee has suggested to us, that maximal integrated information is “the mark” or correlate of consciousness, whereas we still need some underlying (proto-) phenomenal property at the fundamental level that accounts for the Hard Problem (Chalmers 1996). Whether panpsychism is in a better position to account for (a version of the) Hard Problem is an open question—see Chalmers (2016), Goff (2009) and Sebastián (2015). For discussion of the compatibility between panpsychism and IIT see Mørch (2018).
Alternatively, one could claim that states with maximally integrated information are a posteriori identified with phenomenally conscious states; i.e., acknowledge the lack of a priori explanation of consciousness and hold that materialism can be true a posteriori [for discussion see Chalmers (2009)].
Although some proponents of IIT are happy to accept some panpsychist consequences, it is unclear that they do so for reasons related to the Hard Problem. In fact, Tononi and colleagues stress that they take a completely different route with regard to the hard problem, which they take their proposal to address: “IIT addresses the hard problem in a new way. It does not start from the brain and ask how it could give rise to experience; instead, it starts from the essential phenomenal properties of experience, or axioms, and infers postulates about the characteristics that are required of its physical substrate.”(Tononi et al. 2016)
For the purpose of the paper we remain neutral with regard to the relation between IIT and the Hard Problem, as well as between the relation between the Hard Problem and materialism.
Here we are assuming a physicalist position according to which all possible levels of description of a system, e.g., chemical, biological, economical, etc., are, at the end of the day, already present (albeit in an extremely complicated way) in the fundamental, quantum mechanical description.
We thank an anonymous referee for rising this interesting objection.
A related worry is that it would be hard for consciousness to evolve in the early universe because the collapse mechanics would freeze it at an eigenstate with \(\Phi ^{Max}=0\). However, the situation, again, is completely analogous with standard, position-based CSL, which of course can be applied to the early universe without implying that the universe would freeze at some eigenstate of position and nothing would ever move [see Cañate et al. (2013); Okon and Sudarsky (2014, 2016b) for successful applications of standard CSL to the early universe].
One may also worry about the fact that our model does not really lead systems to eigenstates of \(\hat{\Phi }^{Max}\), but only to states which are very close to those eigenstates. As with standard collapse models, if one strictly follows the EE link one gets into trouble because you would have to conclude that our model leads to a scenario in which conscious states never actually occur. The solution, again, as with standard collapse models, is to deviate from the EE link and introduce some type of fuzzy link that ascribes consciousness to states which are close enough to \(\hat{\Phi }^{Max}\) eigenstates. How to define such a “close enough” is still an open question.
In a nutshell, the problem is the following. The argument for the suppression of macroscopic interference via decoherence is that, for all practical purposes, reduced density matrices of systems in interaction with an environment behave as mixtures. However, those reduced density matrices behave as mixtures only if one assumes that, upon measurement, systems collapse à la Copenhague. Therefore, in order for the argument to work, one basically needs to assume what one wants to prove [again, see Okon and Sudarsky (2016a) for details].
References
Adler, S. L. (2007). Lower and upper bounds on CSL parameters from latent image formation and igm heating. Journal of Physics A: Mathematical and Theoretical, 40(12), 2935.
Albert, D. Z. (1992). Quantum mechanics and experience. Cambridge: Harvard University Press.
Albert, D. Z., & Loewer, B. (1996). Tails of schrodinger’s cat. In R. Clifton (Ed.), Perspectives on quantum reality: Non-relativistic, relativistic, field-theoretic (pp. 81–92). Dordrecht: Kluwer.
Allori, V. (2015). Primitive ontology in a nutshell. International Journal of Quantum Foundations, 1, 107–122.
Averill, E. W., & Keating, B. (1981). Does interactionism violate a law of classical physics? Mind, 90, 102–107.
Bassi, A., & Ghirardi, G. C. (2003). Dynamical reduction models. Physics Reports, 379, 257–426.
Bassi, A., Lochan, K., Satin, S., Singh, T. P., & Ulbricht, H. (2013). Models of wave-function collapse, underlying theories, and experimental tests. Reviews of Modern Physics, 85, 471.
Bell, J. S. (1990). Against measurement. In A. I. Miller (Ed.), Sixty-two years of uncertainty. New York: Plenum Press.
Bloch, A. (1885). Exprience sur la vision. Comptes Rendus de Séances de la Société de Biologie (Paris), 37, 493–495.
Block, N. (2002). Some concepts of consciousness. In D. Chalmers (Ed.), Philosophy of mind: Classical and contemporary readings. Oxford: Oxford University Press.
Block, N. (2011). The higher order approach to consciousness is defunct. Analysis, 71(3), 419–431.
Block, N. (2014). Rich conscious perception outside focal attention. Trends in Cognitive Sciences, 18(9), 445–447.
Cañate, P., Pearle, P., & Sudarsky, D. (2013). CSL quantum origin of the primordial fluctuation. Physical Review D, 87, 104024.
Chalmers, D. (2016). The combination problem for panpsychism. In L. Jaskolla & G. Bruntrup (Eds.), Panpsychism. Oxford: Oxford University Press.
Chalmers, D. & McQueen, K. J. (MS). Wave-function collapse theories of consciousness. https://www.youtube.com/watch?v=DIBT6E2GtjA, https://www.youtube.com/watch?v=R-jOfW9UIEA&feature=youtu.be&list=PLl_UXfN1hubVda8RyXj1FLgwK4tW_AqEA&t=2016. Accessed 26 July 2018.
Chalmers, D. J. (1996). The conscious mind: In search of a fundamental theory (1st ed.). Oxford: Oxford University Press.
Chalmers, D. J. (2009). The two-dimensional argument against materialism. In B. P. McLaughlin & S. Walter (Eds.), Oxford handbook to the philosophy of mind. Oxford: Oxford University Press.
Dagasperis, A., Fonda, L., & Ghirardi, G. (1974). Does the lifetime of an unstable system depend on the measuring apparatus? Il Nuovo Cimento A, 21(3), 471–484.
Dirac, P. (1930). The principles of quantum mechanics. Oxford: Oxford University Press.
Everett, H. (1957). ‘Relative state’ formulation of quantum mechanics. Reviews of Modern Physics, 29(3), 454.
Feldmann, W., & Tumulka, R. (2012). Parameter diagrams of the GRW and CSL theories of wavefunction collapse. Journal of Physics A: Mathematical and Theoretical, 45(6), 065304.
Ghirardi, G. C., Rimini, A., & Weber, T. (1986). Unified dynamics for microscopic and macroscopic systems. Physical Review D, 34, 470–491.
Goff, P. (2009). Why panpsychism doesn’t help us explain consciousness. Dialectica, 63(2), 289–311.
Goldstein, S. (2013). Bohmian mechanics. In E. N. Zalta (Ed.), The stanford encyclopedia of philosophy. (Summer 2017 Edn.). https://plato.stanford.edu/archives/sum2017/entries/qm-bohm/.
Hoel, E. P., Albantakis, L., & Tononi, G. (2013). Quantifying causal emergence shows that macro can beat micro. PNAS, 110(49), 19790–19795.
Kremnizer, K., & Ranchin, A. (2015). Integrated information-induced quantum collpase. Foundations of Physics, 45, 889–899.
Larmer, R. (1986). Mind-body interactionism and the conservation of energy. International Philosophical Quarterly, 26, 277–285.
Lockwood, M. (1996). ‘Many Minds’ interpretations of quantum mechanics. The British Journal for the Philosophy of Science, 47, 159–188.
London, F., & Bauer, E. (1939). La théorie de l’observation en mécanique quantique. Actualités scientifiques et industrielles (Vol. 755). Paris: Hermann.
McQueen, K. J. (2015). Four tails problems for dynamical collapse theories. Studies in History and Philosophy of Modern Physics, 49, 10–18.
Mørch, H. H. (2018). Is the integrated information theory of consciousness compatible with russellian panpsychism? Erkenntnis. https://doi.org/10.1007/s10670-018-9995-6.
Oizumi, M., Albantakis, L., & Tononi, G. (2014). From the phenomenology to the mechanisms of consciousness: Integrated information theory 3.0. PLoS Computational Biology, 10(5), 1–25.
Okon, E., & Sebastián, M. A. (2016). How to back up or refute quantum theories of consciousness. Mind and Matter, 14, 1.
Okon, E., & Sudarsky, D. (2014). Benefits of objective collapse models for cosmology and quantum gravity. Foundations of Physics, 44, 114–143.
Okon, E., & Sudarsky, D. (2016a). Less decoherence and more coherence in quantum gravity, inflationary cosmology and elsewhere. Foundations of Physics, 46, 852–879.
Okon, E., & Sudarsky, D. (2016b). A (not so?) novel explanation for the very special initial state of the universe. Classical and Quantum Gravity, 33, 225015.
Pearle, P. (1989). Combining stochastic dynamical state vector reduction with spontaneous localization. Physical Review A, 39, 2277–2289.
Plenio, M. B., & Virmani, S. (2007). An introduction to entanglement measures. Quantum Information and Computation, 7, 1–51.
Price, H., & Corry, R. (Eds.). (2007). Causation, physics, and the constitution of reality: Russell’s republic revisited. Oxford: Clarendon Press.
Saunders, S., Barrett, J., Kent, A., & Wallace, D. (Eds.). (2010). Many worlds? Everett, quantum theory, and reality. Oxford: Oxford University Press.
Scharnowski, F., Hermens, F., & Herzog, M. H. (2007). Bloch’s law and the dynamics of feature fusion. Vision Research, 47, 2444–2452.
Sebastián, M. Á. (2014). Dreams: An empirical way to settle the discussion between cognitive and non-cognitive theories of consciousness. Synthese, 191(2), 263–285.
Sebastián, M. Á. (2015). What panpsychists should reject: On the incompatibility of panpsychism and organizational invariantism. Philosophical Studies, 172(7), 1833–1846.
Stapp, H. (2005). Quantum interactive dualism: An alternative to materialism. Journal of Consciousness Studies, 12, 43–58.
Stapp, H. (2007). Mindful universe. Berlin: Springer.
Tononi, G. (2004). An informational integration theory of consciousness. BMC Neuroscience, 5, 42.
Tononi, G. (2008). Consciousness as integrated information:a provisional manifesto. Biological Bulletin, 215, 216–242.
Tononi, G., Boly, M., Massimini, M., & Koch, C. (2016). Integrated information theory: From consciousness to its physical substrate. Nature Reviews Neuroscience, 17, 450–461.
Tononi, G., & Koch, C. (2015). Consciousness: Here, there and everywhere? Philosophical Transactions of the Royal Society B, 370, 20140167.
von Neumann, J. (1932). Mathematische Grundlagen der Quantenmechanik. Berlin: Springer.
Wigner, E. (1967). Remarks on the mind-body question. In E. P. Wigner (Ed.), Symmetries and Reflections (pp. 171–184). Bloomington: Indiana University Press.
Acknowledgements
We are very grateful to David Chalmers, Martin Glazier, Kelvin McQueen and Manolo Martinez for their useful comments. Financial support for this work was provided by DGAPA projects IG100316 and IA400218.
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Okon, E., Sebastián, M.Á. A consciousness-based quantum objective collapse model. Synthese 197, 3947–3967 (2020). https://doi.org/10.1007/s11229-018-1887-4
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DOI: https://doi.org/10.1007/s11229-018-1887-4