Universal Scaling Laws in Biology: Origins, Applications, Ramifications, and Extensions

Santa Fe Institute, Santa Fe NM

Investigators

Abstract

In this project the PI will further develop and apply ideas from scaling theory that he developed in the past to understand the hierarchical structure and transportation of energy and resources within cells, to investigate similar implications for energy and size distribution of trees and plants within ecosystems, to derive fundamental quantitative theories of sleep and aging, tumor growth and structure, and brain functionality. For example, can it be understood why organisms age and what sets the scale for life-span and, in particular, where in molecular scales 100 years come from for humans? In addition, the paradigm will be extended to address analogous questions in complex network structures of social organizations, such as cities, and to understand the role of innovation and economies of scale in their growth trajectories. Technically, most of the proposed work will be analytic in nature utilizing many of the standard, powerful techniques of theoretical physics, including the language of field theory, the renormalization group, and thermodynamic concepts; when necessary, computer simulations will be employed. In addition, the work will generally be carried out in close, collaboration with biologists, ecologists, biochemists, economists, and other physicists, including post-doctoral fellows and students. The paradigm and principles thus far developed suggest novel ways of attacking many important and fundamental problems across the broad spectrum of biology where quantitative analytic thinking familiar in physics can play a central role. This program aims at establishing a rigorous, quantitative, mathematical, predictive, coarse-grained theory of biological phenomena and to extend it to social organizations. The primary focus has been on energy and material resource use but longer-term the intent is to integrate the energy transport networks with those carrying information, whether genetic or neural, to formulate a unified theory. This work has the potential for having major impact on many highly practical problems in biomedicine (such as the non-invasive study of cardiovascular abnormalities, aging, toxicology and pharmacology, sleep and cancer) as well as providing a conceptual framework for addressing many of societys major problems (including the environment and energy sustainability, and the fate of our cities. The results will be circulated in high-profile scientific journals as well as in more accessible media, including our summer schools, student and high school programs, the SFI business network and by lecturing in other institutions.