The 'Environmental Decoherence' Interpretation Viewed Through Systemic Functional Linguistics

Penrose (2004: 785, 802):

… I should mention a further possibility for interpreting conventional quantum mechanics. This, as far as I can make out, is the most prevalent of the quantum-mechanical standpoints — that of environmental decoherence (c) — although it is perhaps more of a pragmatic than an ontological stance. 

The idea of (c) is that in any measurement process, the quantum system under consideration cannot be taken in isolation from its surroundings. Thus, when a measurement is performed, each different outcome does not constitute a quantum state on its own, but must be considered as part of an entangled state, where each alternative outcome is entangled with a different state of the environment. Now, the environment will consist of a great many particles, effectively in random motion, and the complete details of their locations and motions must be taken to be totally unobservable in practice. …

Holders of viewpoint (c) tend to regard themselves as ‘positivists’ who have no truck with ‘wishy-washy’ issues of ontology in any case, claiming to believe that they have no concern with what is ‘real’ and what is ‘not real’. As Stephen Hawking has said: 

I don’t demand that a theory correspond to reality because I don’t know what it is. Reality is not a quality you can test with litmus paper. All I’m concerned with is that the theory should predict the results of measurements.

My own position, on the other hand, is that the issue of ontology is crucial to quantum mechanics, though it raises some matters that are far from being resolved at the present time.

… the environmental-decoherence viewpoint (c) … maintains that state reduction R [the collapse of the wave function] can be understood as coming about because the quantum system under consideration becomes inextricably entangled with its environment.

Blogger Comments:

From the perspective of Systemic Functional Linguistic Theory, the 'Environmental Decoherence' interpretation of Quantum Theory misconstrues the interdependence of potential as an entanglement of instances (states of the environment).