Beyond Spacetime
Abstract: The early expectations of Bohr and Heisenberg were that the observer must reside outside the representation of the quantum state of a system since (roughly) our experience of the world is classical. According to Stein, the failure to represent ourselves within a physical theory presents an epistemological problem. Recent interpreters of quantum mechanics either deny or attempt to resolve this problem in various ways. In this talk, my focus is on the use of evolutionary and functionalist arguments by Everettians to justify the seeming contradiction between the definite world of experience and the superposed states predicted by unitary quantum evolution. In particular, I examine Saunders’ use of evolutionary arguments in the context of a consistent histories interpretation (in line with Gell-Mann and Hartle’s consideration of observers as Information Gathering and Utilizing Systems) and Wallace’s functionalist argument that a quantum measurement multiplies observers as well as relative states. I conclude by examining a more recent proposal of Zurek that applies Darwinian arguments at the level of primitive quantum states, which (I argue) suggests a possible reapproachment between ontological and epistemological approaches to the quantum state.
Suggested readings:
Stein (1994) Some Reflections on the Structure of Our Knowledge in Physics (http://strangebeautiful.com/other-texts/stein-reflections-struct-knowledge-physics.pdf)
Saunders (1993) Decoherence, Relative States and Evolutionary Adaptation (https://bit.ly/2KI5PlY)
Wallace (2003) Everett and Structure (https://arxiv.org/pdf/quant-ph/0107144v2.pdf)
Zurek (2009) Quantum Darwinism (https://arxiv.org/pdf/0903.5082.pdf)
Source
Tom Pashby: Experience, Evolution and Observers in QM
