Leonard Kelley holds a bachelor's in physics with a minor in mathematics. He loves the academic world and strives to constantly explore it.
Life Requires Physics
Discussing the origins of life is a contested topic for many. Spirituality differences alone make it a challenge to find any consensus or headway on the matter. For science, it’s just as hard to say exactly how inanimate matter became something more. But that may change soon. In this article, we will examine scientific theories for the physics of life, and what that entails.
The theory has its origins with Jeremy England (MIT) who started with one of the most overarching physics concepts known: Thermodynamics. The second law states that the entropy (or disorder) of a system increases as time progresses. Energy is lost to the elements but is conserved overall. England proposed the idea of atoms losing this energy and increasing the entropy of the universe, not as a chance process but more of a natural flow of our reality. This causes structures to form that grow in complexity. England coined the general idea as dissipation-driven adaptation (Wolchover, Eck).
On the surface, this should seem impossible. Atoms naturally restricting themselves to form molecules, compounds, and eventually life? Shouldn’t it be too chaotic for such a thing to occur, especially on a microscopic and quantum level? Most would agree that thermodynamics didn’t offer much help since it deals with nearly perfect conditions. England was able to take the idea of fluctuation theorems developed by Gavin Crooks and Chris Jarynski and see behavior that is far from an ideal state. But to best understand England’s work, let’s look at some simulations and how they operate (Wolchover).
Simulations back up England’s equations. In one take done, a group of 25 different chemicals with varying concentrations, reaction rates, and how outside forces contribute to the reactions, were implemented. The simulations showed how this group would start reacting and eventually would reach a final state of equilibrium where our chemicals and reactants have settled in their activity because of the second law of thermodynamics and the consequence of energy distribution. But England found that his equations predict a “fine-tuning” situation where the energy from the system is utilized by the reactants to the fullest capacity, moving us far from an equilibrium state and into “rare states of extremal thermodynamic forcing” of the reactants. The chemicals naturally realign themselves to gather the maximum amount of energy they can from their surroundings by honing in on the resonant frequency which allows for not only more breaking of chemical bonding but also for that energy extraction before dissipating the energy in the form of heat. Living things also force their environments as we take in energy from our system and increase the entropy of the Universe. This is not reversible because we have sent the energy back out and therefore cannot be utilized to undo my reactions, but future dissipation events could if I wanted. And the simulation showed the time it takes for this complex system to form, meaning that life might not need as long as we thought to grow. On top of that, the process seems to be self-replicating, much like our cells are, and continues to make the pattern that allows for maximum dissipation (Wolchover, Eck, Bell).
A separate simulation done by England and Jordan Horowitz created an environment where the energy needed wasn’t easily assessable unless the extractor was in the right set-up. They found that the forced dissipation still ended up happening as chemical reactions were underway because external energy from outside the system fed into the resonance, with reactions happening 99% more than under normal conditions. The extent of the effect was determined by the concentrations at the time, meaning that it is dynamic and changes over time. Ultimately this makes the path of easiest extraction difficult to map out (Wolchover).
The next step would be to scale the simulations to a more Earth-like setting from billions of years ago and see what we get (if anything) using the material that would have been at hand and in the conditions of the time. The remaining question then is how does one get from these dissipation-driven situations to a life form that processes data from its environment? How do we get to the biology that we around us? (Ibid)
It is that data that drives biological physicists nuts. Biological forms process information and act on it, but it remains murky (at best) as to how simple amino acids could eventually build up to achieve this. Surprisingly, it may be thermodynamics to the rescue again. A little wrinkle in thermodynamics is Maxwell’s Demon, an attempt to violate the Second Law. In it, fast molecules and slow molecules are partitioned on two sides of a box from an initial homogenous mix. This should create a pressure and temperature differential and therefore a gain in energy, seemingly violating the Second Law. But as it turns out, the act of information processing in causing this set-up and the constant effort that entails would itself cause the loss of energy needed to preserve the Second Law (Bell).
Living things obviously utilize information so as we do anything we are expending energy and increasing the disorder of the Universe. And the act of living propagates this, so we could describe the state of life as an outlet of information exploitation of one’s environment and the self-sustaining it entails while striving to limit our contributions to entropy (lose the least amount of energy). Plus, storing information comes at an energy cost so we must be selective in what we remember and how that will impact our future endeavors at optimization. Once we find the balance between all these mechanisms we may finally have a theory for the physics of life (Ibid).
Ball, Philip. “How Life (And Death) Spring From Disorder.” Wired.com. Conde Nast., 11 Feb. 2017. Web. 22 Aug. 2018.
Eck, Allison. “How Do You Say ‘Life’ in Physics?” nautil.us. NautilisThink Inc., 17 Mar. 2016. Web. 22 Aug. 2018.
Wolchover, Natalie. “First Support for Physics Theory of Life.” quantamagazine.org. Quanta, 26 Jul. 2017. Web. 21 Aug. 2018.
© 2019 Leonard Kelley