A
31-year-old researcher from MIT believes he's figured out the basic
physics behind the origin and evolution of life in the universe, a
provocative new theory of life that borrows heavily from 19th century
science.
According to physicist Jeremy England, the origin and evolution of life are processes driven by the fundamental laws of nature — namely the Second Law of Thermodynamics (Details of this law can be found in book of Thermodynamics in Mechanical Engineering). He's come up with a formula showing how a group of atoms, when driven by an external source of energy (like the sun) and when surrounded by a heat bath (like the ocean or atmosphere), can sometimes restructure itself as a way to dissipate increasing rates of mechanical energy. "You start with a random clump of atoms, and if you shine light on it for long enough, it should not be so surprising that you get a plant," England was quoted in Quanta Magazine.
• Here's how Natalie Wolchover describes his work:
At the heart of England's idea is the second law of thermodynamics, also known as the law of increasing entropy or the "arrow of time." Hot things cool down, gas diffuses through air, eggs scramble but never spontaneously unscramble; in short, energy tends to disperse or spread out as time progresses. Entropy is a measure of this tendency, quantifying how dispersed the energy is among the particles in a system, and how diffuse those particles are throughout space. It increases as a simple matter of probability: There are more ways for energy to be spread out than for it to be concentrated. Thus, as particles in a system move around and interact, they will, through sheer chance, tend to adopt configurations in which the energy is spread out. Eventually, the system arrives at a state of maximum entropy called "thermodynamic equilibrium," in which energy is uniformly distributed. A cup of coffee and the room it sits in become the same temperature, for example. As long as the cup and the room are left alone, this process is irreversible. The coffee never spontaneously heats up again because the odds are overwhelmingly stacked against so much of the room's energy randoml concentrating in its atoms. Although entropy must increase over time in an isolated or "closed" system, an "open" system can keep its entropy low — that is, divide energy unevenly among its atoms — by greatly increasing the entropy of its surroundings. In his influential 1944 monograph "What Is Life?" the eminent quantum physicist Erwin Schrödinger argued that this is what living things must do. A plant, for example, absorbs extremely energetic sunlight, uses it to build sugars, and ejects infrared light, a much less concentrated form of energy. The overall entropy of the universe increases during photosynthesis as the sunlight dissipates, even as the plant prevents itself from decaying by maintaining an orderly internal structure...
...[England] derived a generalization of the second law of thermodynamics that holds for systems of particles with certain characteristics: The systems are strongly driven by an external energy source such as an electromagnetic wave, and they can dump heat into a surrounding bath. This class of systems includes all living things.
England then determined how such systems tend to evolve over time as they increase their irreversibility. "We can show very simply from the formula that the more likely evolutionary outcomes are going to be the ones that absorbed and dissipated more energy from the environment's external drives on the way to getting there," he said. The finding makes intuitive sense: Particles tend to dissipate more energy when they resonate with a driving force, or move in the direction it is pushing them, and they are more likely to move in that direction than any other at any given moment.
According to physicist Jeremy England, the origin and evolution of life are processes driven by the fundamental laws of nature — namely the Second Law of Thermodynamics (Details of this law can be found in book of Thermodynamics in Mechanical Engineering). He's come up with a formula showing how a group of atoms, when driven by an external source of energy (like the sun) and when surrounded by a heat bath (like the ocean or atmosphere), can sometimes restructure itself as a way to dissipate increasing rates of mechanical energy. "You start with a random clump of atoms, and if you shine light on it for long enough, it should not be so surprising that you get a plant," England was quoted in Quanta Magazine.
• Here's how Natalie Wolchover describes his work:
At the heart of England's idea is the second law of thermodynamics, also known as the law of increasing entropy or the "arrow of time." Hot things cool down, gas diffuses through air, eggs scramble but never spontaneously unscramble; in short, energy tends to disperse or spread out as time progresses. Entropy is a measure of this tendency, quantifying how dispersed the energy is among the particles in a system, and how diffuse those particles are throughout space. It increases as a simple matter of probability: There are more ways for energy to be spread out than for it to be concentrated. Thus, as particles in a system move around and interact, they will, through sheer chance, tend to adopt configurations in which the energy is spread out. Eventually, the system arrives at a state of maximum entropy called "thermodynamic equilibrium," in which energy is uniformly distributed. A cup of coffee and the room it sits in become the same temperature, for example. As long as the cup and the room are left alone, this process is irreversible. The coffee never spontaneously heats up again because the odds are overwhelmingly stacked against so much of the room's energy randoml concentrating in its atoms. Although entropy must increase over time in an isolated or "closed" system, an "open" system can keep its entropy low — that is, divide energy unevenly among its atoms — by greatly increasing the entropy of its surroundings. In his influential 1944 monograph "What Is Life?" the eminent quantum physicist Erwin Schrödinger argued that this is what living things must do. A plant, for example, absorbs extremely energetic sunlight, uses it to build sugars, and ejects infrared light, a much less concentrated form of energy. The overall entropy of the universe increases during photosynthesis as the sunlight dissipates, even as the plant prevents itself from decaying by maintaining an orderly internal structure...
...[England] derived a generalization of the second law of thermodynamics that holds for systems of particles with certain characteristics: The systems are strongly driven by an external energy source such as an electromagnetic wave, and they can dump heat into a surrounding bath. This class of systems includes all living things.
England then determined how such systems tend to evolve over time as they increase their irreversibility. "We can show very simply from the formula that the more likely evolutionary outcomes are going to be the ones that absorbed and dissipated more energy from the environment's external drives on the way to getting there," he said. The finding makes intuitive sense: Particles tend to dissipate more energy when they resonate with a driving force, or move in the direction it is pushing them, and they are more likely to move in that direction than any other at any given moment.
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