Muddassar Rashid, UK
The 2021 Nobel Prize in Physics is given ‘for groundbreaking contributions to our understanding of complex systems’. Shared between Syukuro Manabe and Klaus Hasselmann ‘for the physical modelling of Earth’s climate, quantifying variability and reliably predicting global warming’ and Giorgio Parisi ‘for the discovery of the interplay of disorder and fluctuations in physical systems from atomic to planetary scales’.
The pressing issues of our times are complex. Of the many that mankind faces today, the challenge of global warming and climate change is at the forefront. It is, therefore, fitting that the Nobel committee has awarded the Nobel Prize in Physics to three individuals who have had an immeasurable impact ‘for groundbreaking contributions to our understanding of complex systems’.
Syukuro “Suki” Manabe was born on the 21st September 1931 in Shinritsu Village in Japan. He majored in meteorology eventually earning his doctorate in 1959 from the University of Tokyo. After continuous spells in the US and Japan, he currently resides as the senior meteorologist at Princeton University, USA. His seminal contribution came in 1967, where the authors used a simple model considering the effects of changes in radiation on a single layer of the atmosphere to calculate the Earth’s surface temperature. They noted that this would increase by 6⁰ Celsius if the carbon dioxide doubled in the atmosphere. Their findings created a crucial link between the greenhouse gases like carbon dioxide and the warming of the Earth.
Parallel to Syukoro’s progress was that of Klaus Ferdinand Hasselmann, also born in 1931. Spending most of his career at the University of Hamburg, and using the works of Syukuro, in 1976 he developed what is now known as the Hasselmann model. In his seminal paper, on ‘Stochastic Climate Models’, he aimed to connect the everyday fast processes that we experience as daily ‘weather’ with the slow varying climate.
The word ‘Stochastic’ is used to describe anything that cannot be predicted precisely but rather has to be analysed using a probability distribution or pattern. There is inherently an element of complexity too great for us to track, but collectively over larger times, there are patterns that we can discern.
This study of complex systems is further recognised by the third recipient of the Nobel Prize in Physics this year, Giorgio Parisi. An Italian theoretical physicist, he is well known for discovering the interplay between disorder and fluctuations in physical systems. This interplay exists between a collection of atoms or at the atmospheric level of an entire planet. Ultimately, he showed that you can model disordered and complex systems by understanding that elements within the system often experience conflicting forces that lead to what is known as frustration. This frustration is born out of the ability of complex systems to keep a memory of how they got there. Ultimately, frustration can be an undesired state, but a state that the system cannot get out of and occupies for a very long time. Using his models, he was able to predict statistical properties of complex systems like supercooled liquids to a flock of starlings.
This is the first time the Nobel committee has awarded the Nobel prize in physics to climate scientists who used complex system physics to understand its nature.
About the Author: Muddassar Rashid is an experimental Physicist in the Department of Physics at King’s College London. His research spans from macroscopic quantum mechanics to stochastic nano-thermodynamics. He currently serves as the Chair of the UK Optomechanical Research Network Seminars Series (UniKORN), the Chairman for the Ahmadiyya Muslim Research Association (AMRA) and as the Deputy Director of Student Affairs (AET) within Ahmadiyya Muslim Youth Association (AMYA).