doi:10.1038/nindia.2017.151 Published online 10 December 2017
Did people in the Bronze Era Indus Valley Civilisation know mathematics? Was it an Indian scientist who laid the foundation for calculus – the mathematical study of continuous change – long before Newton postulated it? How did these ancient milestones contribute to shaping the world’s scientific future, for instance, in quantum computing or synthetic biology?
These and other questions triggered engaging discussions among scientists attending a recent meet (24-28 November, 2017) to mark the hundred years of Bose Institute in Kolkata. The institute, founded by legendary Indian physicist Sir Jagadish Chandra Bose in 1917, hosted two fittingly-themed talk series – ‘History of Indian Science’ and ‘Future of Science’.
Subject experts, who have extensively researched relics of ancient civilisations including age-old texts, offered interesting insights into the piecemeal growth of India’s science, often peppered with tales of individual brilliance.
“Harappans used an ivory scale with divisions, each measuring an average of 1.704 mm,” said archaeologist Vasant Shinde from the Deccan College, Pune, as he talked about the scientific and technical prowess of villagers in the Indus Valley Civilisation. Ivory scales and weight systems unearthed from Lothal, an ancient port city in Gujarat, point to their mathematical knowledge, he said.
Dholavira in Gujarat bears signs that Harappans had excellent knowledge of civil engineering. “They built dams on water channels, irrigated agricultural lands, allotted separate spaces for horticulture and ceremonies, and made check dams of logs and stones to harness and divert river water,” Shinde pointed out. “Remains of silk fibres dated to 2450 BC prove that they probably wove the earliest silk textiles in South Asia.”
The seeds of geometry were also sown in Harappa. “Harappan geometry gave rise to Sulba geometry in Vedic times which laid the foundation of circle geometry,” said P. P. Divakaran from the Chennai Mathematical Institute. “Aryabhata invented trigonometry which subsequently gave rise to discrete calculus,” he said. Aryabhata also offered a distinction between stars and planets, proposing that planetary motion is periodic.
According to Divakaran, all these texts were written in cryptic Sanskrit with very few figures and no equations or symbols. However, ‘Yuktibhasa’, the first textbook on calculus was in Malayalam. “Filled with abstract algebraic structures, this book was written by Jyeshthadeva who lived in Kerala in the 16th century.”
Indian mathematicians invented powerful algebraic methods to generate several rapidly converging series for pi, often compared with those of Leonhard Euler and Srinivasa Ramanujan. But mathematics and other branches of science progressed slowly until the beginning of the 20th Century when physicists pried open the secrets of atoms, subatomic particles and cosmos.
Then came the computers – first analog and then digital – to store and process the astonishing amounts of information in science.
New age quantum computing has made it possible to overcome vulnerabilities of digital computing such as data thefts, said Charles Henry Bennet from the Thomas J. Watson Research Centre, US. In quantum computing, polarised photons carry encrypted information, making it difficult to decode a message. Quantum money and quantum cryptography are examples of such safe transfers of secret information between parties.
Computer science has also revolutionsed biology, helping unravel newer facets every day – from disease-causing genes to friendly gut bacteria. For instance, studies are now linked the role of gut microbes to obesity. “Each person has a unique gut microbial community in a symbiotic relationship with the host,” said Eran Elinav from the Weizmann Institute of Science, Israel. “India has the third largest population of obese children (14 million) after the US and China. Artificial systems can help better understand such microbes,” Elinav said.
Synthetic biology creates artificial systems to mimic and study gene expressions in various types of cells, including cancer and other diseased cells, said Yaakov Benenson from the ETH Zurich, Switzerland. Such artificial systems are useful biological programmes that can be used to make biofuels, biosensors and sensors for monitoring environment, he said. Benenson said the applications of such programmes range from studying the cancer gene to making designer cells for diabetes treatment or therapies for Alzheimer’s disease. Sankar Ghosh from the University of Columbia, US, pointed to an antibody-based drug that can bind to clumps of abnormal protein fragments in the brain of Alzheimer’s patients, alerting the immune system to disintegrate the clumps and flush them out.
Modern molecular biologists and physicists owe their foundation to Jagadish Chandra Bose, said Sibaji Raha of Bose Institute. Bose’s frugal experiments in make-shift labs using materials such as jute, books and sundry metals, led to pathbreaking science. “He was able to make a radiator which could generate 5 mm radiation. He invented a detector known as the spiral spring decoherer – a device that closely resembles today’s multi-contact semiconductor.”