Inquire about purchasing the book | Table of Contents | Annotated Bibliography | Class on Nature of Mind
These are excerpts and elaborations from my book "The Nature of Consciousness"
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Life as Non-equilibrium In the 1960s the Belgian
(but Russian-born) physicist Ilya Prigoginehad a fundamental intuition:
living organisms function as dissipative structures (a term first introduced
by the Ukrainian chemist Alfred Lotka). These are structures that form as patterns in the energy flow and
that have the capacity for self-organization in the face of environmental
fluctuations. In other words, they maintain their structure by continuously
dissipating energy. Such dissipative
structures reside permanently in states of non-equilibrium, unlike inanimate
matter. Life maintains itself far
from equilibrium: the form stays pretty much the same, while the material is
constantly being replaced by new material, part of which comes from matter
(food, air, water) and part of which comes from energy (sun). The flow of
matter and energy through the body of the living organisms is what makes it
possible for the organism to maintain a (relatively) stable form. In order to
stay alive, they have to be always in this state far from equilibrium. Equilibrium is death,
non-equilibrium is life. And here is the solution of
the riddle. Equilibrium is the state of maximum entropy: uniform temperature
and maximum disorder. A system that is not in equilibrium exhibits a variation
of entropy which is the sum of the variations of entropy due to the internal
source of entropy (which tends to increase towards equilibrium) plus the
variation of entropy due to the interaction with the external world. The former
is positive, but the latter can equally be negative. Therefore total entropy
can decrease. An organism
"lives" because it absorbs energy from the external world and
processes it to generate an internal state of lower entropy. An organism "lives" as long as it
can avoid falling in the equilibrium state. (In a sense, organisms die
because this process is not perfect: if our bodies could be made to keep their
shape exactly the same, they would always remain far from the equilibrium and
they would never die). (But then there is a reason
why it is not perfect and we have to die: a stable immutable form of life would
have scant chances of surviving the continuous changes in the environment,
whereas a form of life that continuously reshapes itself has a chance to
evolve with the environment). Thanks to the advent of
non-equilibrium Thermodynamics, it is now possible to bridge Thermodynamics and
evolutionary Biology. By focusing on
entropy, structure and information, it is now possible to shed some light on
the relationship between cosmological evolution and biological evolution. Biological phenomena can be viewed as
governed by laws that are purely physical.
This step might prove as powerful as the synthetic theory of evolution. Prigogines non-equilibrium approach to evolution, i.e. that biological systems
(from bacteria to entire ecological systems) are non-equilibrium systems, has
become a powerful paradigm to study life in the context of Physics. Life can
finally be reduced to a natural phenomenon just like electromagnetism and
gravity. The Austrian physicist Erich
Janschhas extended Prigogines vision of life to the entire universe: the universe as a gigantic
self-organizing system subject to the laws of non-equilibrium thermodynamics. The US chemist Jeffrey
Wickenwent as far as to state that
Thermodynamics is above all the science of spontaneous processes, and link
life with the expansion of the universe. Back to the beginning of the chapter "The Physics Of Life" | Back to the index of all chapters |
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