Quantum Theory: Consciousness Accounted for in Its Own Terms?

Yuri Barzov
6 min readJul 14, 2023

The description of quantum theory given by Erwin Schrödinger — in his famous “cat” paper: The Present Status of Quantum Mechanics [1] written in response to the (equally as) famous “spooky action” paper by Albert Einstein, Boris Podolsky and Nathan Rosen [2] — is entirely information-theoretical but not physical. Eugene Wigner also stressed the need to make a clear distinction between purely information-theoretical language of quantum mechanics and the content that is physics [3]. It looks like much of the ‘weirdness’ of quantum theory emerges from mixing the language with content.

The wave function, according to Schrödinger, is a quantum model that he created to predict observations of microsystems that resisted adequate classical modeling. As an object of knowledge, it has some fundamental features which are very distinct from classical information theory [1].

A quantum model (wave function) of a system deals only with observable magnitudes of a system [4]. On the one hand, observations are the only reality it knows [1]. On the other hand, it has states which do not correspond to physical states of a system [2].

A quantum model of a system, from the moment of its inception, knows everything that can be possibly known about all observable states of the system. Its maximal knowledge is a prerequisite for the model to work. Schrödinger defines the wave function in the role of a model as a maximal catalog of expectations [1].

As a model, the wave function knows all variables that can be observed. No ignorance nor negligence of an experimenter can corrupt this knowledge [1].

As a state, the wave function knows the probabilities of all values of all observable variables for each future observable state of a physical system that it models [1]. The accuracy of probabilities — known to a quantum model since its creation — is also maximal. It cannot be updated by Bayesian inference [5, 6] because there is no room for improvement. In short, von Neumann’s conserved global ensemble entropy for pure states equals zero [5]. Therefore, in the quantum model there is no room for learning either because there is nothing to learn.

The true incompleteness of quantum theory arises from the fact that we may not know a quantum model of a system [1]. Building quantum models of chaotic systems, for instance, requires a lot of quantum magic: that is, computations which are difficult to perform using classical computers [7]. Whenever we do not know a quantum model, we have to rely on a classical model and then classical information theory is applicable.

Quantum theory is not compatible with special relativity because when two systems begin to interact their quantum models do not interact. They merge into a single combined model. Unconditional parameters of each model split into branches conditioned on parameters of other systems in a linear deterministic process evolving according to Schrödinger’s equation. This process of entanglement of models occurs always whenever systems begin to physically interact with each other [1].

Following the reasoning of Schrödinger, decoherence is entanglement of quantum models of systems with the quantum model of the environment, with which those systems physically interact.

Due to decoherence, all physical systems (with only one exception of quasi isolated micro systems) become entangled with their environment, as decoherence is nothing else but nonlocal entanglement with the environment [5]. According to its inventor H.-D. Zeh, decoherence is irreversible for all practical purposes for all physical systems. Zeh reached this conclusion based on the ontic interpretation of quantum theory; assuming that the wave function is not a model but a physical object [5, 8]. Such an assumption automatically leads to the existence of only one wave function of the entire universe (as a physical object) that is splitting continuously into more and more branches as per Everett’s many worlds interpretation of quantum mechanics [5, 6, 8, 9].

According to Schrödinger, however, entanglement can be eluded, if the living subject “decides which branch is taken”; i.e., resolves uncertainty about which branch of the combined (but split inside into conditional branches) wave function should be selected for the resurrection of the unconditional (pure) wave function (model) of one of the entangled systems. When the entanglement is eluded for one model it is eluded for all models, which were entangled as a result of physical interactions. The state of entanglement has corresponding physical states of entangled systems but elusion of entanglement is a purely mental state. Entanglement is continuous. Eluding entanglement looks like a jump, but the wave function is not jumping. Eluding entanglement replaces the old wave function with the new one [1].

Eluding entanglement doesn’t entail the unbundling of past unconditional (pure) wave functions from each other, because during the entanglement they were lost forever. Therefore, we should consider the elusion of entanglement as the resurrection of unconditional models [1].

Following the logic of Schrödinger, quantum theory sometimes models parallel physical states and sometimes represents purely mental states. As we know from Schrödinger’s philosophical writings he considered mental and physical reality as one indivisible mental reality — the universal consciousness [10]. His philosophy in particular enabled him not to see any weirdness or contradictions in quantum theory, which emerge only if we look at quantum theory from the classical point of view — and conflate the language and contents of quantum theory.

“We also recognize that the laws of quantum mechanics only furnish probability connections between results of subsequent observations carried out on a system. It is true, of course, that the laws of classical mechanics can also be formulated in terms of such probability connections. However, they can be formulated also in terms of objective reality. The important point is that the laws of quantum mechanics can be expressed only in terms of probability connections,” Wigner wrote about quantum theory in 1963 [11].

“Consciousness cannot be accounted for in physical terms. For consciousness is absolutely fundamental. It cannot be accounted for in terms of anything else,” Schrödinger said about consciousness in 1931 [12].

Might quantum theory be the first (successful) attempt to account for consciousness in terms of consciousness? If so, the new absolutely unexplored terra incognita lies ahead of us. Isn’t it high time then to venture into it for new discoveries?


  1. Schrödinger, Erwin, The Present Status of Quantum Mechanics, Die Naturwissenschaften 1935. Volume 23, Issue 48.
  2. Einstein, Albert, Podolsky, Boris and Rosen, Nathan. Can Quantum-Mechanical Description of Physical Reality Be Considered Complete?, Physical Review, vol. 47, pages 777–780 (1935).
  3. Wigner E.P. (1995) Remarks on the Mind-Body Question. In: Mehra J. (eds) Philosophical Reflections and Syntheses. The Collected Works of Eugene Paul Wigner (Part B Historical, Philosophical, and Socio-Political Papers), vol B / 6. Springer, Berlin, Heidelberg.
  4. Heisenberg, Werner (1971). Physics and Beyond: Encounters and Conversations. World Perspectives vol. 42. New York: Harper & Row. ISBN 9780049250086. LCCN 78095963. OCLC 15379872
  5. 5. Zeh, H.-Dieter, The strange (hi)story of particles and waves, 2018, arXiv:1304.1003v23 [physics.hist-ph], https://doi.org/10.48550/arXiv.1304.1003
  6. DeWitt, Bryce, Quantum mechanics and reality, Reprinted from Physics Today, Vol. 23, №9 (September 1970).
  7. Goto, Kanato, Nosaka, Tomoki, Nozaki, Masahiro. Chaos by Magic. Eprint arXiv: 2112.14593. Pub Date: December 2021 DOI: 10.48550/arXiv.2112.14593. arXiv: arXiv:2112.14593
  8. Heinrich Päs, Can the Many-Worlds-Interpretation be probed in Psychology? 2017, arXiv:1609.04878v2 [quant-ph], https://doi.org/10.48550/arXiv.1609.04878
  9. Everett, Hugh, “Relative State” Formulation of Quantum Mechanics, Rev. Mod. Phys. 29, 454 — Published 1 July 1957, DOI: https://doi.org/10.1103/RevModPhys.29.454
  10. Erwin Schrödinger, Mind and Matter, 1959, University Press, page 62.
  11. Wigner, Eugene P., The Problem of Measurement, American Journal of Physics 31, 6 (1963); https://doi.org/10.1119/1.1969254
  12. Moore, Walter J. , A Life of Erwin Schrödinger, 1994, Cambridge University Press, page 181 (Moore cites Schrodinger’s answer to a question of J. W. N. Sullivan in a series Interviews with Great Scientists published in The Observer in 1931).