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 the 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; 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. For example, a cup of coffee and the room it sits in become the same temperature. This process is irreversible as long as the cup and the room are left alone. The coffee never spontaneously heats up again because the
odds are overwhelmingly stacked against so much of the room's energy, randomly 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 living things must do this. 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 evolved as they increased their
irreversibility. "We can show very simply from the formula that the more
likely evolutionary outcomes will 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.
Posted by: Er_sanch.
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