Tuesday, January 23, 2018

Emergent stories

Steve Blundell has written a very nice article
Emergence, causation and storytelling: condensed matter physics and the limitations of the human mind

The article is lucid, creative, and stimulating.
He explores some issues that are of particular interest to philosophers such as the differences between "weak" and "strong" emergence, which are sometimes called "epistemological" and "ontological" emergence, respectively.

Part of his argument is based on the fact that human minds are finite and constrained by the physical world and that "information is physical". Unlike the philosophers, he argues that emergence always has both an ontological and an epistemological character.

To illustrate his arguments Steve uses several beautiful examples.

Storytelling.
"To work, stories have to be succinct, told well, have a point and express some truth."
This is to accommodate the physical limitations of the human mind.

Number theory.
Integers are defined by the rules of a very simple algebra. Yet, rich phenomena emerge such as how the asymptotic distribution of prime numbers [given by the zeros of the Riemann zeta function] can be described by random matrix theory.

Conway's game of life.
He considers the "Scattering"  and the creation and destruction of "objects" such as spaceships, "Canada geese" (shown below), and "pulsars".


How emergence comes into play is described by the figure below.

This reminds me a bit of particle physics experiments. New entities emerge from the underlying rules encoded in the Standard Model.

Spin ice.
Emergent gauge field and magnetic monopoles.
This is also discussed as an example of emergence in a 2016 article by Rehn and Moessner.

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