"The paper strips away the nitty-gritty details of cells and biology and describes a simpler, simulated system of chemicals in which it is nonetheless possible for exceptional structure to spontaneously arise—the phenomenon that England sees as the driving force behind the origin of life. “That doesn’t mean you’re guaranteed to acquire that structure,” England explained. The dynamics of the system are too complicated and nonlinear to predict what will happen.
The simulation involved a soup of 25 chemicals that react with one another in myriad ways. Energy sources in the soup’s environment facilitate or “force” some of these chemical reactions, just as sunlight triggers the production of ozone in the atmosphere and the chemical fuel ATP drives processes in the cell. Starting with random initial chemical concentrations, reaction rates and “forcing landscapes”—rules that dictate which reactions get a boost from outside forces and by how much—the simulated chemical reaction network evolves until it reaches its final, steady state, or “fixed point.”...
In these cases, it evolves to fixed points far from equilibrium, where it vigorously cycles through reactions by harvesting the maximum energy possible from the environment... Living creatures also maintain steady states of extreme forcing: We are super-consumers who burn through enormous amounts of chemical energy, degrading it and increasing the entropy of the universe, as we power the reactions in our cells...
Coffee cools down because nothing is heating it up, but England’s calculations suggested
that groups of atoms that are driven by external energy sources can behave differently: They tend to start tapping into those energy sources, aligning and rearranging so as to better absorb the energy and dissipate it as heat. He further showed that this statistical tendency to dissipate energy might foster self-replication...
Understanding what distinguishes life, she added, “requires some explicit notion of information that takes it beyond the non-equilibrium dissipative structures-type process.” In her view, the ability to respond to information is key: “We need chemical reaction networks that can get up and walk away from the environment where they originated.”
https://www.wired.com/story/controversial-new-theory-suggests-life-wasnt-a-fluke-of-biologyit-was-physics/
Physics is so much fun after 1st year physics. And if you are just reading about it and not competing with 300 people for the only A the professor will deign to give out.
FB: Basically, we all learned an over-simplified version of the 2nd law of thermodynamics that ignores possible feedback loops. (i.e. your hot coffee doesn't cool to room temperature if the heat coming off the coffee starts a chain reaction in the air that re-heats your coffee by sucking heat out of your desk) It's super cool.
No comments:
Post a Comment