Extrinsic and intrinsic effects setting viscosity in complex fluids and life processes: the role of fundamental physical constants

TL;DR

This paper explores how both fundamental physical constants and extrinsic factors influence the viscosity of complex fluids in biological systems, highlighting their interplay and implications for understanding life processes.

Contribution

It provides a framework to estimate the bio-friendly range of fundamental constants considering both intrinsic and extrinsic effects on viscosity in complex fluids.

Findings

Extrinsic and intrinsic factors both significantly influence viscosity.

The viscosity of blood with extrinsic effects is close to the intrinsic viscosity from fundamental constants.

The relative importance of factors depends on their variability range.

Abstract

Understanding the values and origin of fundamental physical constants, one of the grandest challenges in modern science, has been discussed in particle physics, astronomy and cosmology. More recently, it was realised that fundamental constants have a bio-friendly window set by life processes involving motion and flow. This window is related to intrinsic fluid properties such as energy and length scales in condensed matter set by fundamental constants. Here, we discuss important extrinsic factors governing the viscosity of complex fluids operating in life processes due to collective effects. We show that both extrinsic and intrinsic factors affecting viscosity need to be taken into account when estimating the bio-friendly range of fundamental constants from life processes, and our discussion provides a straightforward recipe for doing this. We also find that the relative role of extrinsic and intrinsic factors depends on the range of variability of these intrinsic and extrinsic factors. Remarkably, the viscosity of a complex fluid such as blood with significant extrinsic effects is not far from the intrinsic viscosity calculated using the fundamental constants only, and we discuss the reason for this in terms of dynamics of contact points between cells.