Physics Discovery Explains Why Life Can Exist
Scientists discover that fundamental physical constants dictate liquid viscosity, determining if life can survive in the universe.
Imagine a universe filled with stars, planets, and water, yet remains entirely devoid of life. It sounds like science fiction, but new research suggests that even if the chemical building blocks of life are present, the very laws of physics might prevent life from ever taking root.
A groundbreaking study has uncovered a profound connection between the fundamental laws of physics and the biological necessity of fluid movement. According to findings published in Science Advances, the values of the universe's most basic physical constants dictate how liquids flow—a property known as viscosity—which is essential for every living cell to function.
The Viscosity Constraint on Life
At the heart of this discovery is the work of physicist Kostya Trachenko from Queen Mary University of London. His theoretical analysis suggests that the universe operates under a strict constraint: fundamental constants must allow liquids to move in ways that support biological processes.
Life, as we know it, is a masterpiece of movement. Within and between cells, molecules must travel to deliver nutrients, remove waste, and facilitate chemical reactions. This movement relies heavily on diffusion—the natural spreading of particles through a fluid. If the viscosity of these fluids were too high, these vital processes would grind to a halt.
The "Tar" Scenario: Why Small Changes Matter
To understand the stakes, consider the difference between water and tar. Water has low viscosity, allowing it to pour easily and facilitate rapid molecular transport. Tar, however, is thick and resists flow.
Trachenko explains that if the fundamental constants of nature were slightly different, the viscosity of water could change dramatically. "If water were as viscous as tar, life would not exist in its current form or not exist at all," the study notes. This principle isn't limited to water; any hypothetical organism in the universe that relies on a liquid state for biological functions would be subject to these physical limits.
The Mystery of the Constants
Fundamental physical constants—such as the mass and electric charge of an electron or the Planck constant—govern the behavior of atoms, chemical bonds, and even the nuclear reactions that power stars. While these values are considered universal and unchanging, scientists still do not know why they possess the specific values we observe today.
This discovery raises a profound question that sits at the intersection of physics and biology: Why are the fundamental laws of nature so perfectly tuned to allow for the movement of liquids required for life?
By linking the "grand challenge" of understanding fundamental constants to the simple act of how water flows in a cup, researchers have opened a new window into why our universe appears so uniquely suited to foster life.