Ulrich J. Mohrhoff

This essay puts forward a theory of existence that takes its cue from both contemporary physics and Indian Vedanta. The quantum statistics of indistinguishable particles strongly suggests that the “ultimate” constituents of matter, considered out of relation to each other, are identical in the strong sense of numerical identity. This makes it possible to identify each fundamental particle with the vedantic brahman, which relates to the world in a threefold manner: as a substance constituting it (sat), as a consciousness containing it (chit), and as an infinite quality/delight expressing and experiencing itself in finite forms and movements (ananda). The fundamental identity of sat with chit makes it possible to understand how anything material can exist for anything material. The fundamental identity of sat with ananda holds the clue to the free will conundrum. A discussion of a series of vedantically possible worlds solves these problems by showing how they arise and how they become hard. An examination of our place in the vedantic scheme of things at this particular juncture of the drama of evolution is followed by a speculation about the drama’s dénouement.

In resisting attempts to explain the unity of a whole in terms of a multiplicity of interacting parts, quantum mechanics calls for an explanatory concept that proceeds in the opposite direction: from unity to multiplicity. Being part of the Scientific Image of the world, the theory concerns the process by which (the physical aspect of) what Sellars called the Manifest Image of the world comes into being. This process consists in the progressive differentiation of an intrinsically undifferentiated entity. By entering into reflexive spatial relations, this entity gives rise to (i) what looks like a multiplicity of relata if the reflexive quality of the relations is not taken into account, and (ii) what looks like a substantial expanse if the spatial quality of the relations is reified. If there is a distinctly quantum domain, it is a non-spatial and non-temporal dimension across which the transition from the unity of this entity to the multiplicity of the world takes place. Instead of being constituents of the physical world, subatomic particles, atoms, and molecules are instrumental in its manifestation. These conclusions are based on the following interpretive principle and its more direct consequences: whenever the calculation of probabilities calls for the addition of amplitudes, the distinctions we make between the alternatives lack objective reality. Applied to alternatives involving distinctions between regions of space, this principle implies that, owing to the indefiniteness of positions, the spatiotemporal differentiation of the physical world is incomplete: the existence of a real-valued spatiotemporal background is an unrealistic idealization. This guarantees the existence of observables whose values are real per se, as against “real by virtue of being indicated by the values of observables that are real per se.” Applied to alternatives involving distinctions between things, it implies that, intrinsically, all fundamental particles are numerically identical and thus identifiable with the aforementioned undifferentiated entity

Doing justice to quantum mechanics calls for a deeper examination of the relations between our experience, its objects, and its subjects than either third-person interpretations or the first-person singular interpretation of the QBist permit. The metaphysical space opened by Bohr's employment of the "Kantian wedge" between the objective world, about which we can communicate, and the world "in itself" allows quantum mechanics to unfold its metaphysical potential. This in turn makes it possible to go a long way towards bridging the epistemological gap between the empirical and transcendental conceptions of reality.

Although the present paper looks upon the formal apparatus of quantum mechanics as a calculus of correlations, it goes beyond a purely operationalist interpretation. Having established the consistency of the correlations with the existence of their correlata, and having justified the distinction between a domain in which outcome-indicating events occur and a domain whose properties only exist if their existence is indicated by such events, it explains the difference between the two domains as essentially the difference between the manifested world and its manifestation. A single, intrinsically undifferentiated Being manifests the macroworld by entering into reflexive spatial relations. This atemporal process implies a new kind of causality and sheds new light on the mysterious nonlocality of quantum mechanics. Unlike other realist interpretations, which proceed from an evolving-states formulation, the present interpretation proceeds from Feynman’s formulation of the theory, and it introduces a new interpretive principle, replacing the collapse postulate and the eigenvalue–eigenstate link of evolving-states formulations. Applied to alternatives involving distinctions between regions of space, this principle implies that the spatiotemporal differentiation of the physical world is incomplete. Applied to alternatives involving distinctions between things, it warrants the claim that, intrinsically, all fundamental particles are identical in the strong sense of numerical identical. They are the aforementioned intrinsically undifferentiated Being, which manifests the macroworld by entering into reflexive spatial relations.

This paper offers a critique of the Bayesian interpretation of quantum mechanics with particular focus on a paper by Caves, Fuchs, and Schack containing a critique of the “objective preparations view” or OPV. It also aims to carry the discussion beyond the hardened positions of Bayesians and proponents of the OPV. Several claims made by Caves et al. are rebutted, including the claim that different pure states may legitimately be assigned to the same system at the same time, and the claim that the quantum nature of a preparation device cannot legitimately be ignored. Both Bayesians and proponents of the OPV regard the time dependence of a quantum state as the continuous dependence on time of an evolving state of some kind. This leads to a false dilemma: quantum states are either objective states of nature or subjective states of belief. In reality they are neither. The present paper views the aforesaid dependence as a dependence on the time of the measurement to whose possible outcomes the quantum state serves to assign probabilities. This makes it possible to recognize the full implications of the only testable feature of the theory, viz., the probabilities it assigns to measurement outcomes. Most important among these are the objective fuzziness of all relative positions and momenta and the consequent incomplete spatiotemporal differentiation of the physical world. The latter makes it possible to draw a clear distinction between the macroscopic and the microscopic. This in turn makes it possible to understand the special status of measurements in all standard formulations of the theory. Whereas Bayesians have written contemptuously about the “folly” of conjoining “objective” to “probability,” there are various reasons why quantum-mechanical probabilities can be considered objective, not least the fact that they are needed to quantify an objective fuzziness. But this cannot be appreciated without giving thought to the makeup of the world, which Bayesians refuse to do. Doing this on the basis of how quantum mechanics assigns probabilities, one finds that what constitutes the macroworld is a single Ultimate Reality, about which we know nothing, except that it manifests the macroworld or manifests itself as the macroworld. The so-called microworld is neither a world nor a part of any world but instead is instrumental in the manifestation of the macroworld. Quantum mechanics affords us a glimpse “behind” the manifested world, at stages in the process of manifestation, but it does not allow us to describe what lies “behind” the manifested world except in terms of the finished product—the manifested world, for without the manifested world there is nothing in whose terms we could describe its manifestation

Marchildon’s (favorable) assessment (quant-ph/0303170, to appear in Found. Phys.) of the Pondicherry interpretation of quantum mechanics raises several issues, which are addressed. Proceeding from the assumption that quantum mechanics is fundamentally a probability algorithm, this interpretation determines the nature of a world that is irreducibly described by this probability algorithm. Such a world features an objective fuzziness, which implies that its spatiotemporal differentiation does not “go all the way down”. This result is inconsistent with the existence of an evolving instantaneous state, quantum or otherwise.

Quantum mechanics, the fundamental theoretical framework of contemporary physics, supports the following claim: by entering into spatial relations with itself, Brahman creates both space (the totality of existing spatial relations) and matter (the corresponding apparent multitude of relata). The psychological processes by which Brahman enters into spatial relations with itself are discussed by taking a tour of a descending series of supraphysical worlds. [Presented at the International Conference on Indian Psychology, Yoga, and Consciousness, Pondicherry,December 10–13, 2004.]

In a recent article, O. Ulfbeck and A. Bohr [Found. Phys. 31, 757 (2001)] have stressed the genuine fortuitousness of detector clicks, which has also been pointed out, in different terms, by the present author [Am. J. Phys. 68, 728 (2000)]. In spite of this basic agreement, the present article raises objections to the presuppositions and conclusions of Ulfbeck and Bohr, in particular their rejection of the terminology of indefinite variables, their identification of reality with “the world of experience,” their identification of experience with what takes place “on the spacetime scene,” and the claim that their interpretation of quantum mechanics is “entirely liberated” from classical notions. An alternative way of making sense of a world of uncaused clicks is presented. This does not invoke experience but deals with a free-standing reality, is not fettered by classical conceptions of space and time but introduces adequate ways of thinking about the spatiotemporal aspects of the quantum world, and does not reject indefinite variables but clarifies the implications of their existence

What makes it so hard to make sense of quantum mechanics (the theory at the heart of contemporary physics) is the cookie cutter paradigm (a fallacy that is both rooted in our neurophysiological make-up and inherent in the nature of mental consciousness) according to which the world's synchronic multiplicity derives from surfaces that carve up space in the manner of three-dimensional cookie cutters. When liberated from this fallacy, quantum mechanics not only describes the physical world as a manifestation of something very much like the Vedantic Brahman but also describes the process by which this manifestation is effected. It implies that the creative principle to which the physical world owes its existence is supramental rather than mental, in agreement with Sri Aurobindo’s ontology.

The law of energy conservation is either analytic and not threatened by psychophysical interactionism or contingent upon the causal closure of the physical world which interactionism denies. In either case, interactionism implies departures from the laws of physics, despite attempts to demonstrate the contrary by exploiting the loophole of quantum mechanical indeterminism. These departures are best formulated in terms of modifications, by the conscious self, of the electromagnetic interactions between particles. The electromagnetic vector potential is essentially a summary representation of effects on the motion of particles; these effects can be caused by mental events just as well as by physical events. The interactionist hypothesis implies that the modifications caused by the self cannot be described by mathematical laws. Therefore the interactions between particles that are modified by a self cannot take place in strict accordance with any physical law. Interactionism, finally, is not irrevocably committed to dualism: it can be incorporated into a panpsychism which permits the self and the particles constituting the body to be thought of as different aspects of the same causal agent.

How can quantum mechanics be (i) the fundamental theoretical framework of contemporary physics and (ii) a probability calculus that presupposes the events to which, and on the basis of which, it assigns probabilities? The question is answered without invoking knowledge or observers, by interpreting the necessary distinction between two kinds of physical quantities - unconditionally definite quantities and quantities that have values only if they are measured - as a distinction between the manifested world and its manifestation.(The arXived version contains an Appendix which the version published at Cosmology.com lacks. While the latter touches on various ways in which quantum mechanics does not have to do with consciousness, the Appendix concerns what quantum mechanics has to do with consciousness.)

In the first part of the paper a new interpretative principle for quantum mechanics is applied to two kinds of experimental situation. Applied to situations involving distinctions between regions of space, it implies that the spatial differentiation of the physical world is incomplete. This makes it possible to rigorously define the term “macroscopic” and to attribute measurement-independent reality to the positions of macroscopic objects. Applied to situations involving distinctions between things, it warrants the conclusion that intrinsically each fundamental particle is numerically identical with every other fundamental particle. Reality therefore cannot be modelled from the bottom up. Quantum theory’s explanatory arrow points in the opposite direction: from unity to multiplicity. It is the manifestation of an intrinsically undifferentiated Being. In the second part of the paper the work of the Indian philosopher Sri Aurobindo is made use of to explain how consciousness is present in this Being, how it is involved in each fundamental particle, and how it has evolved into our mental consciousness. The role played by the laws of physics in this evolutionary manifestation of Being is discussed, as is the evolution of free will.

The problem of making sense of quantum mechanics is as much a psychological problem as it is a physical one. There is a conflict between (i) the spatiotemporal structure of the quantum world and (ii) the manner in which the phenomenal world is constructed by our minds and/or brains. Both are examined in detail. Unlike the quantum world, the phenomenal world conforms to the cookie cutter paradigm, according to which the synchronic multiplicity of the world rests on surfaces that carve up space much as cookie cutters carve up rolled-out pastry. The attempt to model the physical world in conformity with this paradigm gives rise to pseudo-problems that foil our attempts at making sense of the quantum world. The fact that quantum mechanics, the fundamental theoretical framework of contemporary physics, is essentially an algorithm for calculating the probabilities of measurement outcomes does indeed give rise to genuine problems, but their solution requires the rejection of unwarranted assumptions rather than the making of further such assumptions. The place of causal stories in a world governed by quantum laws is examined, and it is argued that presentism is inconsistent not only with the “block universe” of special relativity but also with the other corner stone of contemporary physics, quantum mechanics. Finally, the conclusions of this essay are situated within the context of the Vedantic theory of existence set forth in a companion essay [Particles, Consciousness, Volition: A Vedantic Vision].

Quantum theory’s irreducible empirical core is a probability calculus. While it presupposes the events to which (and on the basis of which) it serves to assign probabilities, and therefore cannot account for their occurrence, it has to be consistent with it. It must make it possible to identify a system of observables that have measurement-independent values.What makes this possible is the incompleteness of the spatiotemporal differentiation of the physical world. This is shown by applying a novel interpretive principle to interfering alternatives involving distinctions between regions of space. Applying the same interpretive principle to alternatives involving distinctions between things makes it safe to claim that the macroworld comes into being through a progressive differentiation of a single, intrinsically undifferentiated entity. By entering into reflexive spatial relations, this entity gives rise to (1) what looks like a multiplicity of relata if the reflexive quality of the relations is not taken into account, and (2) what looks like a substantial expanse if the spatial quality of the relations is reified. The necessary distinction between two domains (classical and quantum, or macro and micro) and their mutual dependence is best understood as a distinction between the manifested world and its manifestation. [Paper presented at BergeFest, a conference celebrating the 60th birthday of Berge Englert, held at the Centre for Quantum Technologies, National University of Singapore, 22–25 April 2014]

This paper puts forward an ontology that is indebted to QBism, Kant, Bohr, Schrödinger, the philosophy of the Upanishads, and the evolutionary philosophy of Sri Aurobindo. Central to it is that reality is relative to consciousness or experience. Instead of a single mind-independent reality, there are different poises of consciousness, including a consciousness to which “we are all really only various aspects of the One”. This ontology helps clear up unresolved issues in the philosophy of science, such as arise from the reification of quantum states or from disregard of the universal context of science, which is human experience. It further helps clear up unresolved issues in the philosophy of mind, in particular the problem of intentionality and the dilemma posed by the mutual inclusion of self and world.

Reality is not a territory. Reality is an intrinsically undifferentiated Being that manifests the territory, wherein beings capable of mapping the territory evolve. Once fully evolved, these beings will realize their identity with each other and with the Reality manifesting the territory, whereupon their maps will be one with the territory. Freed from the obsession of contemporary interpreters of quantum mechanics with the reification of their calculational tools, quantum mechanics provides deep insights into the atemporal process by which Being has set the stage for its own evolution, that is, for the evolution of beings one with Being and partaking of the power by which Being manifests itself to itself.