Ellis, George F.R. Quantum Theory and the Macroscopic World."
George F.R. Ellis lays out a
thoroughgoing critique of reductionism and a complex ontology for reality as a
whole, drawing from his previous publications and offering new reflections in
light of quantum theory. Against reductionism, Ellis claims that nature is
hierarchically structured, with emergent levels of order and meaning, as well
as bottom-up and top-down action, occurring throughout the hierarchy. He begins
with classical physics, chemistry, and biology, where reductionism is framed in
terms of micro-to-macro relations of bottom-up deterministic causality. But
Ellis notes that quantum processes give rise to the regularities of the
classical world, and that they can have macroscopic results in the classical world.
Elliss examples include amplifiers such as instruments (e.g.,
photomultipliers), biological organs (e.g., the eye) and processes (e.g.
genetic mutations expressed in the organism); coherent implementation of
micro-effects; essentially quantum effects at the macrolevel (e.g.,
superconductivity); and quantum entanglement (e.g. Bose-Einstein condensate).
These examples undermine the reductionist claim that the properties of parts
entirely determine the properties of wholes.
He then gives numerous examples
of macro-to-micro relations indicative of top-down action in physics (e.g.,
nucleosynthesis), in biology (e.g adaptation, expression of genetic
information), and in human volition (e.g., intentions that lead to actions).
Quantum physics provides several ways to understand how these phenomena can
occur at the level of physics: interaction potentials, experiments and the
collapse of the wavefunction, state preparation, decoherence, and the arrow of
time. These features, according to Ellis, discredit reductionism in several
ways. In hierarchically structured systems there is top-down action as well as
bottom-up action. The outcome, even when there is determinism and mechanism at
the microlevel, is partially effected by the context of boundary conditions, macroconstraints,
and macroinfluences. Here systems thinking, based on synthesis, is needed as
well as reductionistic analysis. Quantum entanglement provides another crucial
argument against reductionism. Not only do cooperative effects between
constituents of entangled states modify their individual behavior, but
entanglement makes it hard to speak in terms of independent properties of
constituents parts. Quantum uncertainty further undermines reductionism not
only in microsystems but also in macrosystems when micro-uncertainties are
amplified. Thus simplistic ideas of reductionism, that we are nothing but the
sum of particles controlled by forces at the microlevel, do not hold. They
must be replaced by more sophisticated views integrating both bottom-up (microcausation),
bottom-bottom (co-operative), and top-down (context-setting) interactions.
Still, while Ellis sees reductionism as wrong in principle, reductionism in
practice is legitimate. He offers criteria for when it is suitable (e.g., when
bottom-up causation dominates and microcomponents maintain their individual
properties) and when it is not suitable (e.g., when either top-down causation
is involved or when cooperative phenomena change the behavior of component
parts). He closes this section with comments on two issues related to quantum
theory and ontology: the possibility of chaotic/fractal structures in quantum
processes, and the status of the theoretical and mathematical terms in quantum
theory (e.g., are they human invention or Platonic realities?).
Ellis then develops an
elaborate ontology to describe the many different aspects of material, human,
and ideational reality, building on the works of Popper, Eccles, Penrose and
others. In his hierarchical structure, ontological status and phenomenological
laws of behavior are assigned to higher, as well as lower, levels. His ontology
includes: Worlds 1 (the physical
world), 2 (individual and communal consciousness), 3 (Aristotelian
possibilities), 4 (Platonic abstract realities), and 5 (underlying purpose). He
offers for their foundation and ultimate context, World 0 (God), and he describes the complex ways these Worlds relate to each other. He
concludes with a discussion of Gods action in the world, drawing from his
previous publications with Nancey Murphy. Divine action is kenotic, revealing
Gods purpose and the ethical core of Gods nature through personal religious
experience. Divine action, in turn, requires an openness in physical processes
such that Gods action has real causal effects in the physical world. The
ontological nature of quantum uncertainty provides such openness. The outcome
of quantum measurements are fully under Gods control, while being apparently
random to humans... Such effects at the quantum level can, in turn, affect the
macrolevel without calling on chaos theory or getting entangled in the problem
of quantum chaology. He defends his view of divine action in light of problems
such as quantum randomness, the existence of micro-to-macro effects, the
suggestion that such divine action would be episodic, a possible violation of
the conservation of energy, and other challenges.
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