Tuesday, 17 April 2012
Renormalization, Coarse-Graining, and the Fragile Individual
Santa Fe Institute
12:05 pm, 817R Cathedral of Learning
Abstract: Central to the construction of theories in physics are the related notions of renormalization (or "coarse-graining") and effective field theory. These rely on changing physical scale, and underlie the half-truth that "more fundamental" explanations involve physically smaller objects. Here I show how these concepts carry over to the sciences of the 21st Century, which take as their subjects the biological and social worlds. I show how the loss of physical scale as a defining concept turns questions of coarse-graining and renormalization into questions about the nature and boundary of "the individual." Among other things of interest, this may lead to coherent accounts of downwards causation. Finally, I show for a non-specialist audience how these play out in recent collaborative research into biological and social questions.