What is Life? by Erwin Schrodinger

    Erwin Schrödinger's "What is Life?" is a seminal work that explores the fundamental question of the nature of life from a physicist's perspective. Published in 1944, the book had a significant impact on the development of molecular biology and the understanding of the physical basis of life.

    In the introduction, Schrödinger sets the stage by acknowledging the daunting task of tackling such a broad and complex topic. He notes that the book is based on a series of public lectures he delivered, which allowed him to present his ideas in a more accessible and engaging manner. Schrödinger emphasizes that his approach is that of a physicist, bringing a unique perspective to the study of living organisms.

    In the main body of the book, Schrödinger delves into the complex and intriguing aspects of living organisms, drawing insights from his expertise in quantum mechanics and thermodynamics. He presents a comprehensive review of the key concepts and principles that he believes are essential for understanding the essence of life.

One of your favorite quotes from the book is:

"How would we express in terms of the statistical theory the marvellous faculty of a living organism, by which it delays the decay into thermodynamical equilibrium (death)? We said before: 'It feeds upon negative entropy', attracting, as it were, a stream of negative entropy upon itself, to compensate the entropy increase it produces by living and thus to maintain itself on a stationary and fairly low entropy level."

Explanation:

    This quote eloquently captures Schrödinger's central idea about the nature of life and its relationship with entropy. Schrödinger introduces the concept of "negative entropy" as a fundamental characteristic of living organisms. He argues that living systems maintain a high degree of order and organization, which is in contrast to the natural tendency of the universe towards disorder and entropy (the second law of thermodynamics).

    Organisms actively resist the increase in entropy by continuously extracting "negative entropy" from their environment. This process of "feeding upon negative entropy" allows them to delay the decay into thermodynamic equilibrium, which would be equivalent to death. In other words, living organisms are able to maintain a relatively low entropy state by constantly importing and utilizing the "negative entropy" from their surroundings. This is what Schrödinger refers to as the "marvellous faculty" of living organisms, which sets them apart from the natural tendency towards disorder and decay.

    By framing this concept in terms of the statistical theory of thermodynamics, Schrödinger provides a physical and quantitative basis for understanding the fundamental nature of life and its ability to defy the natural increase in entropy. This quote and the associated concept of "negative entropy" are central to Schrödinger's exploration of the physical basis of life and have had a lasting impact on the scientific understanding of living systems.

1. Negative Entropy and the Order of Living Systems:

    Schrödinger introduces the concept of "negative entropy" as a fundamental characteristic of living organisms. He argues that living systems maintain a high degree of order and organization, which is in contrast to the natural tendency of the universe towards disorder and entropy. Organisms actively resist the increase in entropy by continuously extracting "negative entropy" from their environment, a process that is essential for their survival and growth.

2. Genetic Code and the Aperiodic Crystal:

    Schrödinger proposed the idea of the "aperiodic crystal" as the physical basis of the genetic code. He envisioned the genetic material as a highly ordered, yet aperiodic, structure that could store and transmit the information necessary for the development and maintenance of living organisms. This concept laid the groundwork for the later discovery of the DNA molecule and its role in heredity.

3. Quantum Mechanics and Biological Processes:

    Schrödinger explored the potential role of quantum mechanics in understanding biological processes, particularly in the context of the stability and replication of genetic material. He suggested that the quantum-mechanical properties of atoms and molecules might be crucial in explaining the remarkable fidelity of genetic information transfer and the mechanisms underlying biological processes.

4. Determinism and Free Will:

    Schrödinger delved into the philosophical implications of his scientific ideas, addressing the question of determinism and free will. He argued that the apparent determinism of physical laws does not necessarily preclude the existence of free will, as the complexity of living systems may allow for a degree of indeterminacy and unpredictability.

5. The Meaning of Life:

    In the final chapters of the book, Schrödinger contemplates the deeper philosophical and existential questions surrounding the meaning of life. He explores the relationship between the individual and the universe, the nature of consciousness, and the role of the mind in understanding the physical world.

    Schrödinger's "What is Life?" is a seminal work that has had a lasting impact on the scientific community and the broader understanding of the fundamental principles of life. It has inspired generations of scientists and philosophers to continue exploring the mysteries of the living world and the nature of existence.