Notes & Theories science blog
What is life? The physicist who sparked a revolution in biology
Erwin Schrödinger introduced some of the most important concepts in biology, including the idea of a 'code' of life
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Insights from biology and computing built upon Schrödinger's genius, changing our view of life forever. Photograph: Rick Sammon/AP
Seventy years ago, on 5 February 1943, the Nobel prizewinning quantum physicist Erwin Schrödinger gave the first of three public lectures at Trinity College, Dublin. His topic was an unusual one for a physicist: ...view middle of the document...
Historians and scientists have argued over the influence of Schrödinger's lectures and the book that followed, but there can be no doubt that some of the key figures of 20th century science – James Watson, Francis Crick, Maurice Wilkins and others – were inspired to turn to biology by the general thrust of Schrödinger's work.
The role of the brilliant "code-script" insight is less clear. Reviewers of What is Life? in both Nature and the New York Times noted the novel phrase, but despite the fact that in 1944 Oswald Avery published clear evidence that DNA was the genetic material, virtually no one immediately began looking for – or even talking about – a molecular "code-script" in DNA, although Kurt Stern suggested that the code might involve grooves in a protein molecule, like the grooves in a vinyl disc.
Part of the reason for this lack of immediate excitement and for Avery's discovery not being widely accepted was that DNA was thought to be a "boring" molecule with a repetitive structure – exactly what Schrödinger had said a gene could not be. It took the work of Erwin Chargaff, inspired by Avery, to show that the proportion of the "bases" in the DNA molecule – generally presented by the letters A, T, C and G – differed widely from species to species, suggesting the molecule might not be so boring after all.
As early as 1947, Chargaff suggested that the change of a single base "could produce far-reaching changes … it is not impossible that rearrangements of this type are among the causes of the occurrence of mutations." The culmination of this line of work was Watson and Crick's double helix model, which was based on the experimental data of Rosalind Franklin and Maurice Wilkins.
But in 1947 there was a missing component in biological thinking about the nature of the code, one which was at the heart of Watson and Crick's decisive interpretation of their discovery a mere six years later – "information". That idea entered biology through some applied research carried out to aid the war effort.
In 1943, the US National Research and Development Committee set up a group of scientists to study "fire control" – how to ensure accurate anti-aircraft fire, by the control of information from radar, visual tracking and range-finding. Two of the men involved in this project were Claude Shannon, a mathematician who developed what became known as "information theory" to understand how signals were processed, and...