Basil James Hiley (15 November 1935 – 25 January 2025) was a British physicist and professor emeritus of the University of London.
Long-time colleague of David Bohm, Hiley is known for his work with Bohm on implicate orders and for his work on algebraic descriptions of quantum mechanics in terms of underlying symplectic and orthogonal Clifford algebras.Basil Hiley, website of Maurice A. de Gosson, 2005, accessed on 1 September 2012 Hiley co-authored the book The Undivided Universe with David Bohm, which is considered the main reference for Bohmian mechanics.
The work of Bohm and Hiley has been characterized as primarily addressing the question "whether we can have an adequate conception of the reality of a quantum system, be this causal or be it stochastic or be it of any other nature" and meeting the scientific challenge of providing a mathematical description of quantum systems that matches the idea of an implicate order.
Background Basil James Hiley was born November 15, 1935 in Burma, where his father, James Hiley, worked for the military of the British Raj. He moved to Hampshire, England, at the age of twelve, where he attended secondary school. His interest in science was stimulated by his teachers at secondary school and by books, in particular The Mysterious Universe by James Hopwood Jeans and Mr Tompkins in Wonderland by George Gamow.
Hiley performed undergraduate studies at King's College London. In 1962 he obtained his PhD from King's College in condensed matter physics, more specifically on cooperative phenomena in ferromagnets and long chain polymer models, under the supervision of Cyril Domb and Michael Fisher.
Hiley first met David Bohm during a week-end meeting organized by the student society of King's College at Cumberland Lodge, where Bohm held a lecture. In 1961 Hiley was appointed assistant lecturer at Birkbeck College, where Bohm had taken the chair of Theoretical Physics shortly before. Hiley wanted to investigate how physics could be based on a notion of process, and he found that David Bohm held similar ideas. He reports that during the seminars he held together with Roger Penrose he
Hiley worked with David Bohm for many years on fundamental problems of theoretical physics.See for example the characterization of their work together by Joseph Jaworski in Jaworksi's book Source: The Inner Path of Knowledge Creation, Berrett-Koehler Publishers, 2012 Initially Bohm's model of 1952 did not feature in their discussions; this changed when Hiley asked himself whether the "Einstein-Schrödinger equation", as Wheeler called it, might be found by studying the full implications of that model. They worked together closely for three decades. Together they wrote many publications, including the book The Undivided Universe: An Ontological Interpretation of Quantum Theory, published 1993, which is now considered the major reference for Bohm's interpretation of quantum theory.
In 1995, Basil Hiley was appointed to the chair in physics at Birkbeck College at the University of London.Basil Hiley (short CV), Scientific and Medical Network He was awarded the 2012 Majorana Prize in the category The Best Person in Physics for the algebraic approach to quantum mechanics and furthermore in recognition of "his paramount importance as natural philosopher, his critical and open minded attitude towards the role of science in contemporary culture".Department Fellow wins Majorana Prize, Birkbeck College (downloaded 12 June 2013)The Majorana Prize, www.majoranaprize.com (downloaded 12 June 2013)
Hiley died on 25 January 2025, at the age of 89.
Work
Quantum potential and active information In the 1970s Bohm, Hiley and co-workers at Birkbeck College expanded further on the theory presented by David Bohm in 1952.Paavo Pylkkänen: Foreword by the Editor, in: David Bohm and Charles Biederman, and Paavo Pylkkänen (ed.): Bohm-Biederman Correspondence, , p. xiv They suggested to re-express the field equations of physics in a way that is independent of their spacetime description. They interpreted Bell's theorem as a test of spontaneous localization, meaning a tendency of a many-body system to factorize into a product of localized states of its constituent particles, pointing out that such spontaneous localization removes the need for a fundamental role of the measuring apparatus in quantum theory. They proposed that the fundamental new quality introduced by quantum physics is non-locality. In 1975, they presented how in the causal interpretation of the quantum theory introduced by Bohm in 1952 the concept of a quantum potential leads to the notion of an "unbroken wholeness of the entire universe", and they proposed possible routes to a generalization of the approach to relativity by means of a novel concept of time.
By performing numeric computations on the basis of the quantum potential, Chris Philippidis, Chris Dewdney and Basil Hiley used computer simulations to deduce ensembles of particle trajectories that could account for the interference fringes in the double-slit experiment and worked out descriptions of scattering processes. Their work renewed the interests of physicists in the Bohm interpretation of quantum physics.Olival Freire jr.: A story without an ending: the quantum physics controversy 1950–1970, Science & Education, vol. 12, pp. 573–586, 2003, p. 576 In 1979, Bohm and Hiley discussed the Aharonov–Bohm effect which had recently found experimental confirmation. They called attention to the importance of the early work of Louis de Broglie on pilot waves, emphasizing his insight and physical intuition and stating that developments based on his ideas aimed at a better understanding than mathematical formalism alone.David Bohm, Basil Hiley: The de Broglie pilot wave theory and the further development and new insights arising out of it, Foundations of Physics, volume 12, number 10, 1982, Appendix: On the background of the papers on trajectories interpretation, by D. Bohm, (PDF ) They offered ways of understanding quantum non-locality and the measurement process,David J. Bohm, Basil J. Hiley: Some Remarks on Sarfatti's Proposed Connection Between Quantum Phenomena and the Volitional Activity of the Observer-Participator. Psychoenergetic Systems 1: 173–179, 1976David J. Bohm, Basil J. Hiley: Einstein and Non-Locality in the Quantum Theory. In Einstein: The First Hundred Years, ed. Maurice Goldsmith, Alan Mackay, and James Woudhugsen, pp. 47–61. Oxford: Pergamon Press, 1980 the limit of classicality, interference and quantum tunneling.See also the citation of Bohm and Hiley's article Unbroken Quantum Realism, from Microscopic to Macroscopic Levels by David Hestenes: "Bohm and Hiley, among others, have argued forcefully that the identification of bicharacteristics of the Schrödinger wave function with possible electron paths lead to sensible particle interpretations of electron interference and tunneling as well as other aspects of Schrödinger electron theory." David Hestenes: On decoupling probability from kinematics in quantum mechanics, In: P.F. Fougère (ed.): Maximum Entropy and Bayesian Methods, Kluwer Academic Publishers, 1990, pp. 161–183
They showed how in the Bohm model, introducing the concept of active information, the measurement problem and the collapse of the wave function, could be understood in terms of the quantum potential approach, and that this approach could be extended to relativistic quantum field theories. They described the measurement process and the impossibility of measuring position and momentum simultaneously as follows: "The ѱ field itself changes since it must satisfy the Schrödinger equation, which now contains the interaction between the particle and apparatus, and it is this change that makes it impossible to measure position and momentum together".With reference to Bohm's publication of 1952, cited from Basil J. Hiley: The role of the quantum potential. In: G. Tarozzi, Alwyn Van der Merwe: Open questions in quantum physics: invited papers on the foundations of microphysics, Springer, 1985, pages 237 ff., therein page 238 The collapse of the wave function of the Copenhagen interpretation of quantum theory is explained in the quantum potential approach by the demonstration that information can become inactiveInterview with Basil Hiley conducted by M. Perus, downloaded February 15, 2012 in the sense that from then on "all the packets of the multi-dimensional wave function that do not correspond to the actual result of measurement have no effect on the particle".Basil J. Hiley: The role of the quantum potential. In: G. Tarozzi, Alwyn Van der Merwe: Open questions in quantum physics: invited papers on the foundations of microphysics, Springer, 1985, pages 237 ff., therein page 239
Summarizing Bohm's and his own interpretation, Hiley has explained that the quantum potential "does not give rise to a mechanical force in the Newtonian sense. Thus while the Newtonian potential drives the particle along the trajectory, the quantum potential organises the form of the trajectories in response to the experimental conditions." The quantum potential can be understood as an aspect of "some kind of self-organising process" involving a basic underlying field.B. J. Hiley: Active Information and Teleportation, In: Epistemological and Experimental Perspectives on Quantum Physics, D. Greenberger et al. (eds.), pages 113–126, Kluwer, Netherlands, 1999, p. 7For a "point of view that goes beyond mechanicm", see also Chapter V. of D. Bohm's book Causality and Chance in Modern Physics, 1957, Routledge, The quantum potential (or information potential) links the quantum system under investigation to the measuring apparatus, thereby giving that system a significance within the context defined by the apparatus.B. J. Hiley: Information, quantum theory and the brain. In: Gordon G. Globus (ed.), Karl H. Pribram (ed.), Giuseppe Vitiello (ed.): Brain and being: at the boundary between science, philosophy, language and arts, Advances in Consciousness Research, John Benjamins B.V., 2004, , pp. 197–214, see p. 207 and p. 212 It acts on each quantum particle individually, each particle influencing itself. Hiley cites the wording of Paul Dirac: "Each electron only interferes with itself" and adds: "Somehow the 'quantum force' is a 'private' force. It thus cannot be regarded as a distortion of some underlying sub-quantum medium as was originally suggested by de Broglie".B. J. Hiley: Nonlocality in microsystems, in: Joseph S. King, Karl H. Pribram (eds.): Scale in Conscious Experience: Is the Brain Too Important to be Left to Specialists to Study?, Psychology Press, 1995, pp. 318 ff., see p. 326–327 It is independent of field intensity, thus fulfilling a precondition for non-locality, and it carries information about the whole experimental arrangement in which the particle finds itself.
In processes of non-signalling transmission of qubits in a system consisting of multiple particles (a process that is generally called "quantum teleportation" by physicists), active information is transferred from one particle to another, and in the Bohm model this transfer is mediated by the non-local quantum potential.B. J. Hiley: Active Information and Teleportation, In: Epistemological and Experimental Perspectives on Quantum Physics, D. Greenberger et al. (eds.), pages 113–126, Kluwer, Netherlands, 1999 (PDF)
Relativistic quantum field theory