Throughout the history of science there has always been a close link between physics and what we might consider its sister, chemistry.

In fact, some of the greatest scientists in history, such as the British physicist and chemist Michael Faraday, achieved remarkable results in both disciplines.

Furthermore, physics is not just closely linked to chemistry: the community of physicists interested in biological problems has led to the emergence of an interesting field of research, biophysics. At this point, one might wonder whether biophysics is a branch of physics or simply the application of physics methods to biological problems. But this distinction is irrelevant.

Indeed, since physics underlies chemical processes, and the phenomena that occur within living organisms are nothing other than complex chemical processes, then physics certainly underlies biology. After all, everything, living or inanimate, is subject to the laws of physics.

In the intellectual quest to uncover the fundamental principles that govern the functioning of biology, physicists ask the following question: "What distinguishes life from non-life composed of the same ingredients?" The answer is based on physics: life has the ability to maintain itself in a state of low entropy, far from thermal equilibrium, and is also capable of storing and processing information. Therefore, it stands to reason that a complete understanding of what makes life special should come from fundamental physics.

Furthermore, it's worth remembering that many early advances in molecular biology and genetics in the 20th century were due to physicists such as Leo Szilard, Max Delbrüch, and Francis Crick. Crick, in particular, discovered the double helix structure of DNA, along with James Watson and Rosalind Franklin, and was strongly influenced by the Austrian physicist Erwin Schrödinger, whose remarkable 1944 book, "What Is Life? The Physical Aspect of the Living Cell" remains relevant today.

From an applied perspective, physics has proven fundamental to the development of many of the techniques used to investigate living matter, from X-ray crystallography to magnetic resonance imaging. Even the microscope, without which no biology laboratory could continue its research, was invented by physicists, thanks to centuries of research into the nature of light and the refraction of lenses, culminating in the work of the Dutch optician and naturalist Antoni van Leeuwenhoek and the English physicist, biologist, geologist, and architect Robert Hooke, who studied living organisms with this instrument in the 17th century.

Another particularly interesting area of ​​research is quantum biology, which encompasses recent research in theoretical physics, experimental biology, and biochemistry that seems to suggest an important role for the most counterintuitive ideas of quantum mechanics (such as quantum tunneling, superposition, and quantum entanglement) in the functioning of living cells. Important observations on the functioning of enzymes or the process of photosynthesis seem to require a quantum explanation. This has come as a great surprise to scientists, who are incredulous at the idea that such unique mechanisms could have a significant impact on the workings of life.

We must not forget, however, that life has had nearly four billion years to find advantageous shortcuts. And if quantum mechanics makes a particular biochemical process or mechanism more efficient, then evolution will have used it advantageously.

References

The World According to Physics by Jim Al-Khalili (Originally published: March 3, 2020)