Taking Process Philosophy Seriously

 It was in  Taking Heisenberg’s Potentia Seriously [1] that I first encountered Ruth Kastner's transactional quantum physics (RTI). Michael Epperson, one of the co-authors has written his own book [2] on quantum mechanics that makes extensive use of  the "potentiality" concept. This draws heavily on  Whitehead's Process Philosophy but does not provide new physics, relying on a decoherence narrative, used by many others. Kastner's transactions offer some novel physics in the relativistic formulation, involving an offer and response process. In addition there an interplay process between space-time evens and the quantum substratum potentia. Whitehead's process philosophy (called by him a "philosophy of organism") may provide or be adapted to provide a coherent cosmology encompassing quantum processes and events but the physics of events needs to be formulated too.

The Relativistic Transaction Interpretation is not the only approach to providing a mechanism for quantum state reduction, leading to events, that is not ad hoc. The "Events, Trees and Histories" (ETH) theory, as developed by Jürg Fröhlich and collaborators, also provides a mechanism. As with RTI their approach requires the interaction with massless modes (e.g. photons). However, retro-causality is not invoked. The key concept in ETH is the "Principle of Diminishing Potentialities". This could be interpreted as adding what is missing from Kochen's reformulation of QM, but that is not a point that they make. To provide a rounded understanding of a physics that includes potentiality and processes leading to events a cosmology is needed - an all encompassing philosophical scheme.

An all encompassing philosophical scheme, that includes events and process in the microscopic, mesoscopic and macroscopic scales can only be speculative; but speculation should not be arbitrary.  Following Whitehead [3] 

 .... the philosophical scheme should be coherent, logical, and, in respect to its interpretation, applicable and adequate. Here ‘applicable’ means that some items of experience are thus interpretable, and ‘adequate’ means that there are no items incapable of such interpretation.

‘Coherence,’ as here employed, means that the fundamental ideas, in terms of which the scheme is developed, presuppose each other so that in isolation they are meaningless. ....

The term ‘logical’ has its ordinary meaning, including ‘logical’ consistency, or lack of contradiction, the definition of constructs in logical terms, the exemplification of general logical notions in specific instances, and the principles of inference.

In investigating the implications for quantum physics I hope to gain a deeper understanding of process philosophy and how much of it is applicable. The table below lists key terms introduced in Process and Reality by Alfred North Whitehead and tentatively outlines their relevance to quantum physics. Whitehead also takes common terms  extends, sometimes constrains, and sometimes changes their meaning. For Whitehead, the expansion of language and its use in non-standard ways is not a fault, but is essential to progress in speculative philosophy. 

The list does not replace the need to read the book Process and Reality. This was emphasised by John Cobb, Jr.; I have drawn on his Whitehead Word Book. 

Technical term	Explanation	Possible relevance to quantum physics
Actual Entity or Actual Occasion	An "actual entity" is the fundamental unit of reality, also known as an "actual occasion." It represents a single, concrete event or experience	In quantum physics, actual entities can be seen as quantum events or interactions. Each event is a discrete occurrence, much like how Whitehead describes actual occasions as fundamental units of reality.
Prehension	The process by which an actual entity "grasps" or is influenced by other entities. It is a generalised form of perception or feeling.	This concept can be likened to the way particles interact with each other through forces like electromagnetism or gravity. In quantum physics, entities "prehend" each other by influencing one another's states through these fundamental interactions.
Eternal Object	Abstract entities or pure potentials that actual entities can realize. They resemble universals or  platonic forms.	These can be thought of as the properties that quantum entities can realize. For example, the various possible positions and momenta of a particle. The are represented by self-adjoint operators in the mathematical formulation. Not the wavefunction.
Process	The dynamic nature of reality, emphasizing becoming and change rather than static being.	Quantum physics emphasizes the dynamic nature of particles and fields, constantly in flux and governed by probabilistic laws. This aligns with Whitehead's idea of reality as a process of becoming rather than static being.
Creativity	The ultimate principle of actual existence, representing the continuous creation of new actual entities.	This principle can be related to the inherent unpredictability and novelty in quantum events. Each quantum measurement can result in new, creative outcomes that were not predetermined.  Creation operators are part of standard quantum field theory.
Singular Causality	The specific, individual causes that contribute to an event, as opposed to general or universal causes.	In quantum mechanics, singular causality can be seen in the specific interactions between entities that lead to particular outcomes, such as the collapse of a quantum state.
Nomic Causality	General or universal causes that apply broadly, like scientific laws.	This corresponds to the general laws of quantum mechanics, like the Heisenberg equation, which govern the behaviour of quantum systems as a whole.
Organism	Whitehead's term for the interconnected, interdependent nature of reality, often referred to as "philosophy of organism."	Whitehead's organism concept can be paralleled with the holistic view of quantum systems, where the entire system's behaviour is more than just the sum of its parts. This is a further example of Whitehead extended the meaning of a common concept.
Concrescence	The process by which an actual entity comes into being through the integration of many prehensions.	This process can be compared to the way quantum states evolve over time, integrating various influences and interactions to form a state. But in addition concrescence results in an event.
Subjective Aim	The inherent goal or purpose that an actual entity strives to achieve in its process of becoming.	In quantum physics, this can be related to the inherent tendencies or "aims" of quantum systems to evolve towards certain states, driven by the minimization of energy or other physical principles. This may lead to deeper understanding of how an outcome is selected from probability distribution of possible outcomes and a coherent propensity theory.

In a coming post I will be using some of theses terms to attempt to provide a process ontology for quantum physics. The  "Events, Trees and Histories" (ETH) formulation, as developed by Jürg Fröhlich and collaborators, will be used as the example theory.

1. Ruth  E. Kastner, Stuart Kauffman and Michael Epperson, Taking Heisenberg’s Potentia Seriously, International Journal of Quantum Foundations, March 27, 2018, Volume 4, Issue 2, pages 158-172
2. Michael Epperson, Quantum Mechanics and the philosophy of Alfred North Whitehead, Fordham University Press, 2004 
3. Alfred N. Whitehead, Process and Reality, corrected edition, Simon and Schuster . May 2010 (first published 1929, Cambridge University Press) 

The heart of the matter

The ontological framework for this blog is from Nicolai Hartmann's  new ontology programme that was developed in a number of very substantial publications in the first half of the 20th century. In my interpretation of it, it is the open and pluralistic nature of Hartmann's new ontology that is most attractive. It can include categories of substance, process, organism, consciousness and more. Its layer structure allows the discussion of emergence of multiple entities and supervenience, whatever the ultimate ontological status of the layer model. The openness and pluralism is more important to me than the layered ontology. However many posts have specifically been about quantum mechanics. Quantum mechanics was already making confirmed predictions when Hartmann was writing, and he provided some analysis. I do not think this got much further than identifying that quantum mechanics would provide some ontological challenges.  In Hartmann's layered ontological model the foundation is the  inorganic stratum, with categories such as space, time, process and substance. 

At one stage I thought that the challenges of quantum mechanics could have a solution in epistemology. However, once convinced that the problem was that the physics is incomplete and so the problem was not just that of interpretation. The ontological status of the theory could not be fully addressed without repairing the physics. The major flaw in standard quantum mechanics, as discussed in previous posts, is that there is no physical explanation of events.

As a theory that includes a physical explanation of events,  I am now content to adopt Ruth Kastner's relativistic transactional interpretation (RTI) [1] as a working theory that plugs the holes that were the main concern. For ontological analysis, the most significant aspect of RTI is the nature of the quantum substratum (I have sometimes called this the quantum substrate but there is no distinction intended) and its relationship with the empirical domain. Ruth Kastner does address metaphysical issues [1]  but here and in following posts I will present an independent view. I anticipate that there will be much agreement, but I will concentrate on an analysis of the physics of a universe that is independent of a knowing subject.

Ontological status of quantum substratum

The quantum substratum is a domain of potentiality. It is not only not observable; it is not actual. The only indictor of its nature is the mathematical theory that relates it to actual events. This mathematical theory could be treated as  a mere prediction and technology instrument. However I want to examine how the universe could be in itself. The potentiality substratum is real in that it is the source of physical events. 

A potentiality interpretation of quantum mechanics is not an innovation of RTI. It was proposed by Heisenberg [2] and is championed by researchers who do not adopt RTI [3]. The three authors, it seems, could not agree with Ruth Kastner on adopting RTI as the best current explanation. The other authors are strongly influenced by A N Whitehead's process metaphysics. On a first pass, a metaphysics with a fundamental event and process ontology, such as Whitehead's, seems consistent with RTI. however, there are many details and interpretations of Whitehead's metaphysics that I have yet to engage with.

In RTI events take place due to a transaction process in the substratum. Processes in the quantum substratum are disposed to create events that manifest in space-time and shape the future potential manifestation of events (objective quantum state reduction). The process can be summarised:

1. The physical system, described by relativistic quantum mechanics, evolves to a state that is favourable to a set of possible transactions
2. The context of these possible transactions (at a given time in the substratum dynamics) and the state of the system defines a complete set of transition probabilities from a complex of incommensurable possible transitions.
3. One of the possible transitions takes place. This is, as far as the mathematical description guides,  a physical stochastic process step. 
4. The outcome is a space-time event and a change in the substratum state conditioned on that event.

Why should a quantum substratum of pure potentiality give rise to space-time events? In the mathematical structure describing the physics of the substratum time is a category and, space and momentum are among the potentialities. It would be conceivable that events would appear in a space-time block universe. Alternatively it is the relationship among the events that constitute space-time [1]. Space-time is emergent and not ontological fundamental if the events the elements of its fabric. Fundamentally there are no substances. For example, quantum states describing electrons represent  entities that cannot exhibit all their potential attributes at the same times. The picture in which quantum mechanics is a modification of classical mechanics that can keep the substance-particle as the fundamental ontology is no longer defendable. Classically Matter is fundamental, now, in the quantum description adopted here,  matter-like entities emerge in a dynamic network of event relationships. This is a profound ontological innovation even greater than the introduction of electromagnetic fields.

Whatever the final status of a layered ontology turns out to be, I think that it will be useful in examining how, in detail, a substratum of pure potentiality can give rise to a rich world of physics, biology, psychology, society and culture. 

References

1. Ruth E. Kastner, The Transactional Interpretation of Quantum Mechanics - A Relativistic Treatment, Cambridge University Press, 2nd edition 2022
2. Heisenberg, W (1958). Physics and Philosophy: The Revolution in Modern Science, New York: Harper.
3. Ruth  E. Kastner, Stuart Kauffman and Michael Epperson, Taking Heisenberg’s Potentia Seriously, International Journal of Quantum Foundations, March 27, 2018, Volume 4, Issue 2, pages 158-172