Philosophy of Physics Seminar (Thursday - Week 4, TT22)

How do living organisms maintain their highly ordered low entropy states? And might quantum mechanics play a role in this, as hinted at by Schrödinger in his celebrated book, What is Life? Quantum biology is an exciting new field of interdisciplinary research, bringing together theoretical physics, computational chemistry and molecular biology, but it remains speculative and, some might say, even controversial. However, growing evidence is showing that non-trivial quantum effects, such as long-lived coherence, quantum entanglement and tunnelling may well play a functionally important role inside living cells. For example, enzymes utilise quantum tunnelling to accelerate biochemical reactions, while plants and bacteria make use of quantum coherence in photosynthesis to determine the most efficient route for photons from sunlight to reach the reaction centre where they can be converted into chemical energy. More intriguingly, it appears that some animals use quantum entanglement – what Einstein called “spooky action at a distance” – to ‘see’ the earth’s magnetic field for directional information. 

In this talk I trace the origins of the field back to the 1930s, and examine how fragile quantum mechanical mechanisms previously thought to be confined to highly rarefied laboratory environments at temperatures close to absolute zero, might manage to play a role in the wet, warm biological world. I will also report on our latest results showing the importance of proton tunnelling in DNA and how this can lead to genetic mutations.