Quantum Biology :
When I was studying at University, about 60 years ago, those who pursued Biology had a non-mathematical descriptive and classification approach, to the living world which was quite different from those who pursued Physics, usually in combination with Chemistry and Mathematics. And it was in Physics that one learnt about the Quantum world of sub-atomic particles.
But today there is a collaboration between these seemingly incompatible scientific fields that is producing fascinating new insights into the nature of the living world.
This relatively new discipline of “quantum biology” builds on the idea that the ‘oddities’ of quantum mechanics such as entanglement, quantum tunnelling, superposition of wave states, the uncertainty principle and quantum coherence play vital roles in the biology of living things.
The concept of “interdisciplinarity” is all the rage in academia these days: widely divergent fields come together to hybridise their insights and find new ways of seeing the world. It started with relatively simpler ideas like Chemical Physics, Bio-Physics, Materials Science, Molecular Biology and so on.
Quantum biology is one such meeting point. And while it is producing remarkable and novel findings about olfaction, photosynthesis, the action of enzymes, and an understanding of the brain itself, the interdiscipline is as old as the quantum revolution itself.
Although the origin of quantum biology is often thought to be Erwin Schrödinger’s 1944 book What is Life?, the field actually dates back to the late 1920s, just as the mathematical underpinnings of quantum mechanics were established.
Biology in the early twentieth century was still torn between two philosophical outlooks. The first was the mechanistic worldview of the Scientific Revolution: in particular, Rene Descartes’ theory that organisms were not much more than soulless machines.
The other was the notion of “vitalism”, which took the spotlight in the early nineteenth century. This was the belief that there was something fundamentally different and even mysterious about living organisms, and that their function and make-up could not be reduced to mere classical chemistry and physics. Some vital spark, or élan vital, marked life from non-life.
As early as 1929, Niels Bohr was making vague allusions to the role of quantum thinking in biology, and although such a vision was not yet fleshed out by Bohr himself, he inspired others. Bohr returned to the topic later, this time arguing that complimentarity, or wave-particle duality (the idea that quantum objects act as both particles and waves, but never both at the same time) was the organicist “new law” that would uncover the mysteries of the living world. Together with Werner Heisenberg, Bohr wondered if such quantum phenomena played an undiscovered role in the mutation and selection of Darwinian evolution.
In the 1940s Erwin Schrödinger argued that genes and the laws of heredity were sensitive to quantum mechanical dynamics and that the mutations necessary for natural selection arose through quantum tunnelling (the phenomena whereby subatomic particles can reach lower energy states by bypassing, or tunnelling through, intervening higher energy states).
These musings in What is Life? partly inspired Francis Crick and James Watson to investigate the nature and structure of genes.
However, with the incredible breakthroughs in molecular biology that were to follow, much of life’s mechanics were explained using classical chemistry, without recourse to quantum phenomena.
Further reflection in physics pointed out that much of the interesting aspects of quantum mechanics depended on a system being completely isolated from its environment, which was particularly unlikely, as McFadden and Al-khalili note, in the “hot, wet and complex system in such a living cell”. By the 1960s quantum biology slumped, with most researchers being “dismissive of the notion that quantum mechanics played any kind of special role in living systems”.
Several scientists kept thinking about the connection between quantum mechanics and life, however, with some, such as British mathematical physicist Roger Penrose, even drawing connections between the quantum world and consciousness. But for the most part, many of the early claims of quantum biology were discredited and the classical sciences remained dominant in biology.
However, in the past few decades quantum biology has experiencing something of a revival.
There are also some tantalising findings to suggest that the “hot, wet and complex” biological systems, non-equilibrium systems fundamentally connected to their environment, might actually promote interesting quantum dynamics, rather than rule them out has had been thought in the sixties.
The question has now become how quantum phenomena affect biology, rather than if they do.
“They may have had to wait many decades, but the quantum pioneers were indeed right to be excited about the future of quantum biology.”
Over the past decade, the field of quantum biology has seen an enormous increase in activity, with detailed studies of phenomena ranging from the primary processes in vision and photosynthesis to avian navigation.
Photosynthesis is a highly optimized process from which valuable lessons can be learned about the operating principles in nature. Its primary steps involve energy transport operating near theoretical quantum limits in efficiency. Recently, extensive research was motivated by the hypothesis that nature used quantum coherences to direct energy transfer.
Much of the brain’s physiological activity is currently understood as being performed through the firing of neurons to transmit information, send instructions and interpret stimuli through the senses, all of these phenomena central to the functioning of the vast neural network that we identify as our self, our consciousness.
Drawing on earlier research suggesting that quantum effects in protein filaments known as microtubules, found in neurons, play a role in the nature of consciousness, Adams and Petruccione recently investigated ( https://avs.scitation.org/doi/abs/10.1116/1.5135170%40aqs.2020.AQB2020.issue-1?journalCode=aqs ) the state of research into whether quantum effects contribute to neural processing and describe what experimental evidence there is to support the theories.
If supported experimentally, this knowledge could, they say, shape thinking about how we think. The duo also suggests that, as these fields of research grow, quantum computing and quantum neurobiology might also inform each other in ever-increasing ways.
This write up has drawn upon material from this source:https://cosmosmagazine.com/biology/indeterminate-nature-the-resurgence-of-quantum-biology
Some useful additional links :
Introduction to Quantum Biology by Philip Ball : https://youtu.be/bLeEsYDlXJk
Quantum Biology : Q&A: https://youtu.be/AlN6zVrUewM
Quantum Biology: the hidden nature of nature: https://youtu.be/ADiql3FG5is
How Quantum Biology may explain life’s biggest questions? https://youtu.be/_qgSz1UmcBM