Sunday, October 01, 2017

What is Life?


scribd |  Schrodinger unleashed modern molecular biology with his “What Is Life?”.[1] The order in biology must be due, not to statistical processes attributable to statistical mechanics, but due to the stability of the chemical bond. In one brilliant intuition, he said, “It will not be a periodic crystal, for these are dull. “Genes” will be an aperiodic crystal containing a microcode for the organism.” (my quotes around “genes”.) He was brilliantly right, but insufficient. 

The structure of DNA followed, the code and genes turning one another on and off in some vast genetic regulatory network. Later work, including my own,[2] showed that such networks could behave with sufficient order for ontogeny or be enormously chaotic and no life could survive that chaos.

We biologists continue to think largely in terms of classical physics and chemistry, even about the origins of life, and life itself, despite Schrodinger’s clear message that life depends upon quantum mechanics.
 
In this short article, I wish to explore current “classical physics” ideas about the origin of life then introduce the blossoming field of quantum biology and within a newly discovered state of matter, The Poised Realm, hovering reversibly between quantum and “classical” worlds that may be fundamental to life. Life may be lived in the Poised Realm, with wide implications.

The widest implications are a hope for a union of the objective and subjective poles; the latter lost since Descartes’ Res cogitans failed and Newton triumphed with classical physics and Descartes’ Res extensa. What I shall say here is highly speculative.

2 Classical Physics and Chemistry Ideas about the Origin of Life
There are four broad views about the origin of life:
1) The RNA world view, dominant in the USA.
2) The spontaneous emergence of “collectively autocatalytic set”, which might be RNA, peptides, both, or other molecular species.
3) Budding liposomes or other self-reproducing vesicles.
4) Metabolism first, with linked sets of chemical reaction cycles, which are autocatalytic in the sense that each produces an extra copy of at least one product per cycle. 

Almost all workers agree that however molecular reproduction may have occurred, it is plausibly the case that housing such a system in a liposome or similar vesicle is one way to confine reactants. Recent work suggests that a dividing liposome and reproducing molecular system will synchronize divisions, so could form a protocell, hopefully able to evolve to some extent.[3]