Physics has long failed to explain life—but researchers are testing a groundbreaking new theory in the lab

Everything from the behavior of vast galaxy clusters to the spin of the smallest atom may be explained by modern physics. It cannot, however, explain life. The distinction between a live and dead mass of substance can't be explained by any formula. Life appears to "emerge" inexplicably from non-living components, such basic particles.

The framework of assembly theory, a daring new hypothesis that aims to explain life at its most basic level, was just published in Nature. It is assumed that its fundamental components are information and complexity, like DNA. The theory offers a means of comprehending how these ideas arise in chemical systems.

When something is greater than the sum of its parts, like water, it might feel wet even when individual water molecules don't, a phenomenon known as "emergence" is used by physicists to describe it. A quality that emerges is wetness.

Despite the sophisticated mathematics, laboratory testing is eventually necessary for the theory to be deemed trustworthy. Experiments with meticulous design, like the one my colleagues and I are conducting at the moment, will be necessary to anchor the abstractions of assembly theory in the physical world of chemistry.

The fundamental tenet of assembly theory is that items may be classified according to their formation history rather than as unchangeable entities. This causes the procedures by which basic building components are assembled into complex structures to come into focus.

According to the idea, there is a "assembly index" that measures the shortest path or least number of steps needed to construct an item. The degree of "selection" required to produce an ensemble of objects—a reference to the memory, like DNA, needed to generate live things—is tracked by this metric.

Living things, like helium in stars, do not merely happen by accident. They need DNA as a template in order to produce new versions.

Expectations of originality

However, how may these theoretical ideas be investigated by experimentation? We have already tested one important component of assembly theory in our lab. This is how the assembly index is calculated using mass spectrometry, an analytical technique that calculates the mass-to-charge ratio in molecules.

We can determine a molecule's assembly index by breaking it up and examining its mass spectra. The number of steps required for different fragments to come together to create a particular molecule is actually visible to us. Other methods, such as NMR and infrared spectroscopy, can also be used to assess the assembly index for different kinds of molecules.

We have computed the assembly index on a variety of compounds both computationally and in the lab. Our research demonstrates that chemicals that are specifically linked to life, like carbon dioxide, are not inherently as complicated or require as much information to assemble, as do molecules like hormones and metabolites (byproducts of metabolic processes). Indeed, as the theory predicts, we have demonstrated that molecules related to life are the only ones exhibiting an assembly index greater than 15 steps.

Additionally, the hypothesis provides verifiable explanations for the genesis of life. This is due to the theory's assertion that there exists a threshold, or moment at which molecules become sufficiently complex that they require memory and knowledge to replicate themselves, marking the transition from non-life to life.

Ultimately, in non-biological systems (like our sun, which generated the planets by bringing together a ton of mass), selection and little memory are feasible. However, without great memory and selection capacities, neither living things nor the technology they develop—be it Lego or rocket science—are possible.

Chemical-based soup

By producing a kind of chemical soup in our lab, we want to look more carefully at this beginning of life. Over time, new molecules may form in this soup as a result of random reactions or the addition of other reactants, and we will be able to track their assembly index and the system's progress. We could investigate that exciting transition point from non-life to life and find out whether it agrees with assembly theory predictions by adjusting reaction rates and circumstances.

Additionally, we are creating "chemical soup generators," which combine basic substances to produce complicated ones. These might advance our knowledge of how assembly theory can be used to build complexity and how selection can occur outside of biology.

This may reveal something about the early evolution of life, which required less selection at initially and more and more as time went on. Are items made in predictable ways under the same conditions? Or does chance come into play at some point? This would enable us to determine whether life emerged in a deterministic, predictable manner or in a more chaotic one.

As a result, assembly theory may have far wider applications. Beyond molecules, research on other systems that depend on combinations, including material aggregates, polymers, or artificial chemistry, may be motivated by the framework. This might result in fresh discoveries in science or technology. It could show minute patterns in which molecules with assembly indices over a threshold disproportionately have particular characteristics.

The hypothesis might potentially be applied to in-depth research on evolution itself. Studies might look at how tiny molecules that combine to form nucleotides and amino acids form cell fragments during the process of building a whole cell. This kind of tracking the evolution of metabolic and genetic networks may provide insights into historical changes in evolution.

However, there are difficulties with experimental testing. Efficient tracking of object assembly requires accurate experimental monitoring.

However, it may be quite worthwhile. Assembly theory holds the potential to reveal universal principles of hierarchical formation that go beyond biological boundaries, offering a profoundly new explanation of matter.

It's possible that complex arrangements of matter are only markers in an endless creation process that extends across time rather than unchangeable entities. The universe is ultimately creative even if it abides by certain physical rules.

Provided by The Conversation