An international team of scientists, led by researchers from Arizona State University and the University of Glasgow, have proposed a new framework called 'Assembly Theory' to bridge the gap between physics and evolution. The researchers aim to unify inert and living matter by considering objects not only in their current state but also through the dimension of time, accounting for their formation and potential to change. Building on their previous work on a molecular complexity index, the team developed a mathematical framework for defining the amount of selection required to produce complex objects, such as proteins or eyes, from molecular building blocks.
Assembly Theory is based on the minimal number of steps needed to construct an object, its minimal memory, and the object's copy number, considering its abundance in the world. The copy number is crucial as the likelihood of an object's existence diminishes as its complexity increases unless external forces or pressures assist in defying the odds over time – akin to the process of evolution through selection.
Using the foundations of assembly theory, the researchers quantified the degree of selection and evolution needed to produce a range of evolved objects, from molecules to cellular structures. Notably, the theory is not limited to existing objects but can also predict the emergence of new ones. This predictability could be applied to understand the possibility of life emerging in different systems, such as Saturn's moon Titan.
The researchers plan to refine their work to understand how assembly theory can define life. Moreover, the theory can be tested experimentally in a laboratory setting, potentially shedding light on life elsewhere in the Universe and the mystery of how life originated on Earth. The team sees assembly theory as a transformative approach at the intersection of physics, chemistry, biology, and information theory, with implications for fields ranging from cosmology to computer science.