Editor's comment

In 1933, Erwin Schrodinger won the Nobel Prize for his work in theoretical physics. He developed a general wave-equation that treated electrons in an atom as waves and could successfully predict electron behavior in chemical changes. This changed the paradigm of sub-atomic particles.They became particle/waves with only a statistical probability of being here or there.

In this essay, Schrodinger ventured into the field of biology and anticipated the characteristics of the DNA molecule that was then unknown. The essay is included here because of its discussion of entropy and the quantum world-view.


Schrodinger, Erwin What Is Life? Anchor Books Doubleday & Co, Garden City, New York 1956 [abstract— 230 words] — living organisms and entropy

The 2nd Law of Thermodynamics expresses the tendency of all nature systems to become disordered. When the requirements of a microscopic hereditary molecule are considered it must be durable enough to withstand the bombardment of activity on the subatomic level. It must be an unusually large molecule and a masterpiece of highly differentiated order.

Living systems “keep going” for much longer periods than we would expect. When an inanimate system “is isolated or placed in a uniform environment, all motion usually comes to a standstill very soon as a result of various kinds of friction; differences of electric or chemical potential are equalized, substances which tend to form a chemical compound do so, temperature becomes uniform by heat conduction. After that, the whole system fades away into a dead, inert lump of matter. A permanent state is reached, in which no observable events occur.” The physicist calls this ‘maximum entropy’.

[Ed's note: A system has increasing entropy when it becomes uniform, when that which was special and organized becomes unspecial and unorganized or disordered. If a system has low entropy, it is in a very unordered (stable) state. To move from disorder to order (from unspecial to special) requires an input of energy.]

It is by postponing this decay into maximum entropy, avoiding breakdown that distinguishes a living organism. An organism maintains its orderliness by absorbing orderly things from its environment, food in the case of animals, and sunlight in plants.