Papers by Ulrich Mohrhoff
In a couple of recent publications, Granville Sewell, who is Professor of Mathematics at the Univ... more In a couple of recent publications, Granville Sewell, who is Professor of Mathematics at the University of Texas El Paso, argued that evolution violates the second law of thermodynamics in a spectacular way. Specifically, he noted that if an increase in order is extremely improbable when a system is closed, it is still extremely improbable when the system is open, unless something is entering which makes it much less improbable. The Darwinist’s argument of “compensation” is logically flawed: an extremely improbable event is not rendered less improbable by the occurrence of other events that are more probable. Order can increase in an open system, not because the laws of probability are suspended when the door is open, but because order may walk in through the door. If we found evidence that DNA, auto parts, computer chips, and books entered through the Earth’s atmosphere at some time in the past, then perhaps the appearance of humans, cars, computers, and encyclopedias on a previous...
arXiv (Cornell University), Jun 26, 2000
] and others to the counterfactual use of the ABL rule are shown to be groundless. In particular,... more ] and others to the counterfactual use of the ABL rule are shown to be groundless. In particular, this use is not restricted in the way Kastner has claimed. A variant of the three-box experiment due to Vaidman is discussed. It is argued that Born probabilities (and hence state vectors or density operators) are not the right basis for drawing ontological inferences. What quantum mechanics is trying to tell us about the world must be inferred from the objective ABL probabilities that are assigned to counterfactuals. The correct inferences, however, will remain incomprensible until a prevalent but inconsistent way of thinking about the temporal aspect of the world is rejected.
Manifesting the Quantum World (the Short Version)
arXiv (Cornell University), Apr 29, 2014
Quantum theory's irreducible empirical core is a probability calculus. While it presupposes the e... more 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 (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. 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.
arXiv (Cornell University), Aug 29, 2005
This is a comment on a collection of statements gathered on the occasion of the Quantum Physics o... more This is a comment on a collection of statements gathered on the occasion of the Quantum Physics of Nature meeting in Vienna.
arXiv (Cornell University), Feb 21, 2001
According to d'Espagnat we must choose between nonlinear breaks in quantum state evolution and we... more According to d'Espagnat we must choose between nonlinear breaks in quantum state evolution and weak objectivity. In this comment it is shown that this choice is forced on us by an inconsistent pseudo-realistic interpretation of quantum states. A strongly objective one-world interpretation of linear quantum mechanics is presented. It is argued that the weak objectivity favored by d'Espagnat is, in fact, inconsistent with quantum mechanics.
arXiv (Cornell University), Aug 1, 2001
Theories of decoherence come in two flavors-Platonic and Aristotelian. Platonists grant ontologic... more Theories of decoherence come in two flavors-Platonic and Aristotelian. Platonists grant ontological primacy to the concepts and mathematical symbols by which we describe or comprehend the physical world. Aristotelians grant it to the physical world. The significance one attaches to the phenomenon of decoherence depends on the school to which one belongs. The debate about the significance of quantum states has for the most part been carried on between Platonists and Kantians, who advocate an epistemic interpretation, with Aristotelians caught in the crossfire. For the latter, quantum states are neither states of Nature nor states of knowledge. The real issue is not the kind of reality that we should attribute to quantum states but the reality of the spatial and temporal distinctions that we make. Once this is recognized, the necessity of attributing ontological primacy to facts become obvious, the Platonic stance becomes inconsistent, and the Kantian point of view becomes unnecessarily restrictive and unilluminating.
Several errors in Stapp's interpretation of quantum mechanics and its application to mental causa... more Several errors in Stapp's interpretation of quantum mechanics and its application to mental causation (Henry P. Stapp, "Quantum theory and the role of mind in nature," e-Print quant-ph/0103043, to appear in Foundations of Physics) are pointed out. An interpretation of (standard) QM that avoids these errors is presented.
arXiv (Cornell University), Apr 4, 2016
How can quantum mechanics be (i) the fundamental theoretical framework of contemporary physics an... more 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.
arXiv (Cornell University), May 26, 2000
The problem of understanding quantum mechanics is in large measure the problem of finding appropr... more The problem of understanding quantum mechanics is in large measure the problem of finding appropriate ways of thinking about the spatial and temporal aspects of the physical world. The standard, substantival, set-theoretic conception of space is inconsistent with quantum mechanics, and so is the doctrine of local realism, the principle of local causality, and the mathematical physicist's golden calf, determinism. The said problem is made intractable by our obtruding onto the physical world a theoretical framework that is more detailed than the physical world. This framework portraits space and time as infinitely and intrinsically differentiated, whereas the physical world is only finitely differentiated spacewise and timewise, namely to the extent that spatiotemporal relations and distinctions are warranted by facts. This has the following consequences: (i) The contingent properties of the physical world, including the times at which they are possessed, are indefinite and extrinsic. (ii) We cannot think of reality as being built "from the bottom up", out of locally instantiated physical properties. Instead we must conceive of the physical world as being built "from the top down": By entering into a multitude of spatial relations with itself, "existence itself" takes on both the aspect of a spatially differentiated world and the aspect of a multiplicity of formless relata, the fundamental particles. At the root of our interpretational difficulties is the "cookie cutter paradigm", according to which the world's synchronic multiplicity is founded on the introduction of surfaces that carve up space in the manner of three-dimensional cookie cutters. The neurophysiological underpinnings of this insidious notion are discussed. "I feel that the real joke that the eternal inventor of enigmas has presented us with has absolutely not been understood as yet." Albert Einstein [1, p. 411]
arXiv (Cornell University), Jul 2, 2001
Epistemic interpretations of quantum mechanics fail to address the puzzle posed by the occurrence... more Epistemic interpretations of quantum mechanics fail to address the puzzle posed by the occurrence of probabilities in a fundamental physical theory. This is a puzzle about the physical world, not a puzzle about our relation to the physical world. Its solution requires a new concept of physical space, presented in this article. An examination of how the mind and the brain construct the phenomenal world reveals the psychological and neurobiological reasons why we think about space in ways that are inadequate to the physical world. The resulting notion that space is an intrinsically partitioned expanse has up to now stood in the way of a consistent ontological interpretation.
Foundations of Physics, May 17, 2014
In resisting attempts to explain the unity of a whole in terms of a multiplicity of interacting p... more 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.
arXiv (Cornell University), Sep 11, 2014
QBism (short for Quantum Bayesianism) is a novel interpretation of quantum mechanics. With its ra... more QBism (short for Quantum Bayesianism) is a novel interpretation of quantum mechanics. With its radical emphasis on the subject, QBism provides a welcome corrective to popular misrepresentations of the epistemological reflections of Niels Bohr, while Bohr, rightly understood, can take the edge off QBism's radical subjectivism. Together, they form a winning combination, the key to which is Schrödinger's concept of objectivation, which has its roots in Kant's theory of science. Objectivation contrasts with objectification, the demonstrably futile attempt to make measurements yield outcomes in interpretations that reify a calculational device. Apart from providing an in-depth discussion of QBism, Kant, and Bohr, the paper addresses the issue of nonlocality, the scenario of Wigner's friend, Bell's shifty split, and the problem of the now. It also outlines an ontological interpretation that incorporates the insights of QBism and Bohr.
arXiv (Cornell University), May 17, 2003
The question of what ontological message (if any) is encoded in the formalism of contemporary phy... more The question of what ontological message (if any) is encoded in the formalism of contemporary physics is, to say the least, controversial. The reasons for this state of affairs are psychological and neurobiological. The processes by which the visual world is constructed by our minds, predispose us towards concepts of space, time, and substance that are inconsistent with the spatiotemporal and substantial aspects of the quantum world. In the first part of this chapter, the latter are extracted from the quantum formalism. The nature of a world that is fundamentally and irreducibly described by a probability algorithm is determined. The neurobiological processes responsible for the mismatch between our "natural" concepts of space, time, and substance and the corresponding aspects of the quantum world are discussed in the second part. These natural concepts give rise to pseudoproblems that foil our attempts to make ontological sense of quantum mechanics. If certain psychologically motivated but physically unwarranted assumptions are discarded (in particular our dogged insistence on obtruding upon the quantum world the intrinsically and completely differentiated spatiotemporal background of classical physics), we are in a position to see why our fundamental physical theory is a probability algorithm, and to solve the remaining interpretational problems.
arXiv (Cornell University), Sep 1, 2000
What has so far prevented us from decrypting quantum mechanics is the Cookie Cutter Paradigm, acc... more What has so far prevented us from decrypting quantum mechanics is the Cookie Cutter Paradigm, according to which the world's synchronic multiplicity derives from surfaces that carve up space in the manner of three-dimensional cookie cutters. This insidious notion is shown to be rooted in our neurophysiological make-up. An effort is made to liberate the physical world from this innate fallacy.
The frontiers collection, 2018
Reality is not a territory. Reality is an intrinsically undifferentiated Being that manifests the... more 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.
arXiv: Quantum Physics, 2014
Quantum theory's violation of remote outcome independence is assessed in the context of a nov... more Quantum theory's violation of remote outcome independence is assessed in the context of a novel interpretation of the theory, in which the unavoidable distinction between the classical and quantum domains is understood as a distinction between the manifested world and its manifestation.
This article points out a nonlocality of quantum mechanics that is significantly more radical tha... more This article points out a nonlocality of quantum mechanics that is significantly more radical than that implied by violations of Bell locality or Einstein locality. It consists in the fact that the spatiotemporal differentiation of the physical world is incomplete. The so-called parts of space only exist to the extent that they are physically realized, and arbitrarily small parts cannot be physically realized. Further it is shown that intrinsically all fundamental particles are identical in the radical sense of numerical identity. Hence it is impossible to model reality "from the bottom up," whether on the basis of an intrinsically and completely differentiated space or spacetime or out of a multitude of intrinsically distinct building blocks. Quantum theory's explanatory arrow points in the opposite direction — from unity to multiplicity. In addition to establishing these conclusions, the article examines their implications for the enterprise called physics, illuminat...
Journal of Nonlocality, Jun 20, 2013
If when thou sittest alone, still & voiceless on the mountaintop, thou canst perceive the revolut... more If when thou sittest alone, still & voiceless on the mountaintop, thou canst perceive the revolutions thou art conducting, then hast thou the divine vision and art freed from appearances. (Sri Aurobindo, 1997, p. 437) Not long after launching the PEAR Odyssey, Jahn and Dunne (2011) realized that far more fundamental epistemological issues were at stake, and far stranger phenomenological creatures were on the prowl than we had originally envisaged, and that a substantially broader range of intellectual and cultural perspectives would be required to pursue that trek productively. They came to believe that the sundry anomalous physical phenomena that originally attracted our attention are deeply rooted in, and therefore significantly indicative of, a much more fundamental, profound, and ubiquitous metaphysical dynamic whose ultimate comprehension holds far richer potential for human benefit than the more explicit phenomenal curiosities with which we began. By allowing "epistemological penetration beyond the superficial 'margins' of reality into the depths of its essential 'Source'," the tantalizing research reported by Jahn and Dunne provides "a glimmer of a vast, poorly charted domain for future human exploration, comprehension, and utilization." This domain is not as poorly charted as the authors believe. Its "fundamental, profound, and ubiquitous metaphysical dynamic" has been deeply and systematically explored by Sri Aurobindo, who outlined its geography in language that both integrates and transcends the dominant intellectual and cultural perspectives of the West and of the East.
This article points out a nonlocality of quantum mechanics that is significantly more radical tha... more This article points out a nonlocality of quantum mechanics that is significantly more radical than that implied by violations of Bell locality or Einstein locality. It consists in the fact that the spatiotemporal differentiation of the physical world is incomplete. The so-called parts of space only exist to the extent that they are physically realized, and arbitrarily small parts cannot be physically realized. Further it is shown that intrinsically all fundamental particles are identical in the radical sense of numerical identity. Hence it is impossible to model reality "from the bottom up," whether on the basis of an intrinsically and completely differentiated space or spacetime or out of a multitude of intrinsically distinct building blocks. Quantum theory's explanatory arrow points in the opposite direction — from unity to multiplicity. In addition to establishing these conclusions, the article examines their implications for the enterprise called physics, illuminat...
There are reasons to doubt that making sense of the wave function (other than as a probability al... more There are reasons to doubt that making sense of the wave function (other than as a probability algorithm) will help with the project of making sense of quantum mechanics. The consistency of the quantum-mechanical correlation laws with the existence of their correlata is demonstrated. The demonstration makes use of the fact (which is implied by the indeterminacy principle) that physical space is not partitioned "all the way down," and it requires that the eigenvalue-eigenstate link be replaced by a different interpretive principle, whose implications are explored.
Uploads
Papers by Ulrich Mohrhoff