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What is Life?

drichard's picture


What is life?
            What is life? Is that not the ultimate question? Is that not what we have been driving towards all semester? As a final assignment I decided to read Erwin Schrödinger’s much alluded to What is Life? A seminal work of modern science, the book does not proffer an answer to the question that glosses its cover page, but rather offers a particularly insightful perspective on the development of an answer. Schrodinger was a master physicist responsible for imperative advancements in the field of quantum mechanics. This work is a deviation from his mathematical proofs; here we see the theoretical analyst trying to bridge an important gap between his statistical science and that of the real-time, real-space science of organisms: biology. The result is an intriguing, ingenious piece of modern thought bound to claim a permanent spot within the scientific canon. The following is a general discussion of the book in relation to our ongoing discussion of life this semester.
            At the opening of the book Schrödinger asks, “How can events in space and time which take place within the spatial boundary of an organism be accounted for by physics and chemistry?” (3). In other words, what does the field of theoretical physics have to offer biology? Schrödinger begins his discussion with a treatise on the heritability of traits over generations. He comments on the astounding perseverance of certain inherited characteristics. He makes note of the marked durability of genetic material; it persists over thousands of years. This continuity, and, indeed, any continuity, is in direct contradiction to one of the tenets of the laws of physics: all systems of matter [i.e. the universe] are moving toward a final state of entropy [or disorder]. Essentially, Schrödinger attempts to reconcile the durability of hereditary material, which is made out of the same atoms as all matter [from which classical physics arose], with theoretical physics and the relatively small size of the chromosome [which would, in a vacuum, make it more susceptible to the random motion of atoms and, thus, the blind “pull” of entropy].
His description of genetics in the face of classical physics illuminates the improbability of the occurrence of individual life, a theme that we have discussed at length. At one point, Schrödinger traces a phenotypic trait back to his paternal grandfather; he notes the variety inherent in sexual reproduction. Over the great number of potential sex partners, his grandfather chose his grandmother. They recombined their already improbable genetic materials [which had inevitably mutated, at least slightly, since their respective births] and conceived Erwin’s father, who then replicated the process with his wife. During Erwin’s conception [and every conception since the beginning of time] there occurred the distinct potential for crossing over. What are the chances that this highly improbable progression of genetic transfer resulted in Erwin’s improbable body, in Erwin’s further improbable consciousness? Indeed, what are the chances, within our universe, that genetic material should exist at all? The answer to each question: exceedingly slim to absolutely none. In this way, individual life is extremely improbable, but even more improbable is the relatively “frequent” occurrence of individual lives.
How does Schrödinger account for the continuity of not only genetic material, but also the body as a whole? How do the atoms that comprise the body retain their human form in direct opposition to the rules of the surrounding universe? His answer has three parts. For one, genetic material and the resulting body are fashioned with molecules, or groups of atoms that behave as singular entities, as environments unto themselves. The second part accounts for the continuity of the body in terms of its size. Because it is so large, it is not affected by Brownian motion, the random movement of atoms. Schrödinger notes, the path of movement of an atom undergoing Brownian motion “shows what funny and disorderly experience we should have if our senses were susceptible to the impact of a few molecules only. There are bacteria and other organisms so small that they are strongly affected by this phenomenon. Their movements are determined by the thermic whims of the surrounding medium; they have no choice” (14). The final answer posed by Schrödinger is the idea that, through metabolism of natural resources, the body achieves “negative entropy.” It defies the laws of physics and, in essence, transcends the universe in which it occurs.
An essential extension of this notion of metabolism concerns the effect our consumption of has on our environment. The natural material from which we harvest energy [an apple, for example] is returned in a modified form to the universe from which it was obtained [human waste]. The second law of thermodynamics states that no system can decrease in entropy without increasing the entropy of another system. In consuming natural resources we are accelerating the rate at which the universe is approaching entropy, the final equilibrium. We are increasing the disorder of the universe.
With this resistance to the entropic motion of the universe we see the introduction of intentionality to the universe. It appears that the very thing that makes the conception of the universe possible is responsible for its deterioration. This is a rather prominent issue in modern consciousness. It is manifested primarily in the debate over global warming. Many activists believe that we should look to preserve our environment, to be conscientious of the effects our actions have on rates of entropy [i.e. global warming]. To these skeptics I would argue that human consciousness, human consumption, and the conscious intention to consume resources are all naturally occurring, amoral events. The imposition of an ethic on a blind universe seems fruitless. If we are to be stewards of the earth we should do it for the prospect of future humanity, not for trees or squirrels.
The final implication of Schrödinger’s position on life’s resistance to the entropic motion of the universe is a new definition of death. An organism dies when it can no longer resist entropic motion; in death, the organism succumbs to disorder and its matter returns to the more probable state of equilibrium.
            In the face of the improbability of organic composition, especially in terms of Schrödinger’s book, it is essential to understand the fundamental difference between the statistical, environment-dependant science of theoretical physics and that of biology, the science of life. Life does not occur within a vacuum. Insofar as this is true, the application of theoretical physics to improbable living systems is problematic. The “space and time” of Schrödinger’s physics differs fundamentally from the space and time in which life occurs. Schrödinger acknowledges this difference and purports the solution to be a kind of “new physics,” a “biophysics.” In order to understand the physical properties of the body we have to throw away classical physics and develop new bases for thought with the body constituting an entirely new physical environment. This new environment would dictate new laws with which analysts could statistically predict the movement of objects within the body.
            A final area of interest is mentioned in passing, indeed almost dismissed by Schrödinger, concerns the idea that atoms have no definite spatial boundary. The building block of the universe as we know it is not a block at all, in the traditional sense: it is merely an approximation. An atom is mostly space to begin with. It has no set composition: electrons float in and out of the approximate bounds, joining other atoms and causing chemical reactions. This fluidity is at once startling; in the face of this fact all of our old beliefs about solid objects in external reality prove false. This notion relates to our discussion of spatial continuity earlier in the semester. We all agreed, upon observing a lab table, that it was not moving and that it had a definite boundary. If the universe is in flux, constantly moving toward entropy, and if the fundamental units of matter are really approximations of empty space, where do our notions of physical constancy and solidity come from? For the answer to this question we turn inside of ourselves. It seems that our sense of external, certain reality exists in our minds only.
            In closing, I found Schrödinger’s What is Life? to be the perfect end to the semester. Not only did it provide an insightful basis for much of our discussion this semester, it provoked new and important questions concerning the function of intentionality within the universe. What role does intentionality play in the perseverance of formal continuity of the body? It also allowed for new definitions of life and death: life for Schrödinger is a particular assembly of molecules that resists the entropic tendencies of the universe and death is the defeat of this resistance as the organism succumbs to the blind pull of equilibrium. Certainly Schrödinger’s explorations will bring us closer to the final definition of life [if one is, in fact, to be found].
Works Cited
Schrödinger, E. What is Life? Mind and Matter. New York: Cambridge UP, 1967. Print.



Paul Grobstein's picture

physics, biology, and life

"the very thing that makes the conception of the universe possible is responsible for its deterioration"

Maybe, more positively, "the very thing that is responsible for its deterioration makes the conception of the universe possible"?

"our sense of external, certain reality exists in our minds only."

Maybe, more positively, "our minds create a sense of external reality and so need not be constrained by it"?

"The imposition of an ethic on a blind universe seems fruitless"

Maybe, more positively, "since the universe doesn't have one, we are free to explore ethics ourselves"? 

"the body ... defies the laws of physics and, in essence, transcends the universe in which it occurs."

Maybe, more accurately, "the body reflects the open-ended possibilities inherent in the laws of physics, and in turn expands the open-ended possibilities of the universe"?