Black Swan (24 Sept. 2015)
Reviewed by June Raymond
Jim Al-Khalili is a physicist and well-known broadcaster while Johnjoe McFadden is a professor of molecular biology. Together, they lead us into a new scientific world in which physics and biology talk to one another – and the results are very exciting.
In the past quantum physics pretty much had the monopoly of physics, and biology was limited to the world of classical science. The experiments by which the quantum world was understood required very precise conditions which are not found in the messy world of Nature. However, as this book demonstrates life at every level depends on the movement of fundamental particles that are governed by quantum rules.
Central to this is the wave-particle duality whereby, as in the ‘two slit’ experiment, a single atom can take on a wave function, holding the possibility of many different positions at the same time as it makes its journey, before it reappears as a particle when it arrives at its destination. Without this phenomenon photosynthesis would be impossible as the photon from the sun, which the plant captures in order to combine with carbon, would have lost all its energy if it had to travel according to classical physics rather than making what scientists call a quantum walk. All animal and plant life depends in some way upon the sugars that are created in this process.
Equally essential to life are the enzymes responsible for breaking down and repairing cells; they speed up processes which would otherwise take impossibly long periods of time. We are given the example of how tadpoles lose their tails and grow legs, which involves removing hard gristly matter. For this particles must move through apparently impossible energy barriers by means of what is called quantum tunnelling.
Another essential for life is the work of genes. Interestingly Schrödinger insisted 70 years ago that the accuracy involved in the replication of genes was impossible in classical physics and could only be achieved by quantum means. This was before the discovery of DNA and no one then took him seriously. Now it is an area of intensive research.
Mutations in DNA replication are reckoned to be one in a billion, and fascinating discoveries have shown that it is a mechanism that stretches back to the beginning of life on Earth. While it is obviously vital that the reproduction of genetic codes has almost total fidelity, the mutations are important so that life can develop. I love the notion that imperfection is built in at this level as necessary for life. Other examples of quantum action in biology are still being researched; they include how birds and some animals are able to find their direction using the Earth’s magnetic poles and the sense of smell. Animals’ noses can be so sensitive that for example a bear can scent a carcass from over 20 kilometres.
The last chapters include a discussion of mind, consciousness and what life actually is. While I am in awe of the science and research that has gone into the writing of this book the writers lose me when it comes to wider matters. They ‘protest too much’. When it was first proposed that a bird’s compass might depend on a quantum-entangled pair mechanism it was dismissed by scientists as ‘pseudoscientific’ – along with many of the other breakthroughs the authors describe. Yet these writers see no contradiction when they say that the claims of telepathy and the ability of dogs to know when their owners are coming home have ‘no scientific merit’. While they acknowledge the importance of electromagnetic fields in consciousness, once again they emphasise that this in no way supports ‘so-called paranormal phenomena’ or ‘spirituality’. But reading this book I cannot help wondering if we may be on the verge of a quantum revolution in science, and whether perhaps Rupert Sheldrake and morphic resonance, to which mainstream scientists are so hostile, are just a little nearer to becoming mainstream science.