round 300 BC, a philosopher (as scientists were then known) called Aristarchus was fascinated by solar and lunar eclipses. He asked whether they were caused by the gods.

Aristarchus studied the heavens carefully and reached a bold conclusion: he drew diagrams that showed the relationship between the Sun, the Earth and the Moon. His remarkable conclusion was the deduction that the Earth was not the centre of the universe. Rather, it orbited around the Sun.

This arrangement, Aristarchus concluded, explained all eclipses that he had been interested in. When the Moon casts its shadow on the Earth, it is a solar eclipse; when the Earth shades the Moon, it is a lunar eclipse. The discovery makes him a true scientific pioneer and a very important person to have inspired people to take a rational approach to understanding Nature.

Another significant question he raised was that of the ingredients of this vast and ever-expanding universe. The first ingredient is matter: dusk, land, rocks, liquid, ice and everything we see around us. It also includes the vast clouds of gas, massive spirals of stars, each of them containing billions of suns and every object stretched away incredibly distant.

The second is energy. Sun produces massive energy, ninety-three million miles away from the Earth.

The third is space. The universe is such a spacious entity that whatever you may call it, it cannot be labelled as cramped. Stretching in all directions, there is more and more space. Where do these three ingredients come from?

An answer was provided by Albert Einstein. He concluded that matter and energy are actually two sides of the same coin. Thus, instead of three, the universe is formed of two ingredients, i.e. energy and space.

Where did all the energy and space come from? These were spontaneously invented in an event called the Big Bang. Another mystery – how an entire fantastically enormous universe of space and energy can materialise out of nothing – was solved later by one of the strangest facts about our cosmos. The laws of physics demanded the existence of ‘negative energy’. When the Big Bang produced a very large amount of positive energy, it also produced a similar amount of negative energy simultaneously. In this way, the positive and negative add up to zero, always zero.

Something wonderful happened at the Big Bang instant. It started time. This phenomenon was explained and popularised in a famous book, A Brief History of Time, written by Stephen Hawking. The significant words, “Be brave, be curious, be determined, overcome the odds. It can be done” were uttered by Hawking.

His celebrity status was at its apogee when, watched by millions of people, he opened the Paralympic Games in London in 2012. He was diagnosed in his youth with a neuron disease that crippled him, making him weaker throughout his lifetime. Yet he continued to contribute to theoretical physics and mathematics along with astronomy.

A wonderful movie that captures his life, times and works is The Theory of Everything. Eddie Redmayne played Hawking in the movie. Hawking became the pride of Cambridge University and contributed in many fields of theoretical physics yet he would often say, “If I have made a contribution.” He might be the only person who would have added the ‘if’ to that sentence. Everyone else was pretty sure he had. He contributed enormously to black hole research and wrote many popular books. After his death, Hawking was buried near Newton and Charles Darwin in Westminster Abbey, the highest honour given to a British citizen.

In our part of the world, Ruchi Ram Sahni (1863-1948) in colonial times had the idea of popularising science. Born in a Sahni family of Bhera, he was a scientist, educator, businessman, social reformer and a public intellectual. He established The Punjab Science Institute and Scientific Workshop in 1888 with the objectives of “popularisation of all kinds of scientific knowledge throughout the province by means of lectures illustrated with experiments and lantern slides as well as the publication of tracts.” After a couple of years, the objectives included the encouragement of technical education, in particular, of chemical industries. For this purpose, cash prizes were offered by Malik Jowala Sahai of Miani (near Bhera) for short papers on the manufacture of soap, indigo and such industries.

Sahni and his team delivered popular lectures on scientific topics throughout the Punjab to popularise scientific attitudes in public mind. On April 26, 1893, according to The Tribune newspaper, Sahni “gave a very interesting lecture on physical science at Gujranwala. He spoke in Punjabi, and so many people came to hear him that there was not room enough for half of them.” He made arrangements with a mistri (technician) named Allah Bakhsh, employed in the Railway Workshop for manufacturing scientific instruments for schools and college laboratories and for commercialising those.

It became such a success that at the Calcutta Exhibition of 1906, for instance, Sir Jagadish Chandra Bose was on the Committee of Judges for the Department of Scientific Exhibits. He praised the contribution to the exhibition of Sahni’s Workshop and, like at many other places, a gold medal was awarded to it.

Sahni’s determination for scientific pursuits was so intense that at the age of fifty-one, he began pursuing research on radioactivity, a subject in which he had long been interested. In 1914, he moved to the Hochschule, in Karlsruhe in Germany, but had to leave for England due to the onset of WWI. In England, he joined the famous Manchester Laboratory, where he worked under the guidance of Ernest Rutherford and Neil Bohr. This research was published in the Philosophical Magazine in 1915 and 1917.

In addition to writing textbooks and delivering public lectures on science, Ruchi Ram Sahni took an interest in the practical work of agriculture extension. At the request of the Agricultural Department of the Punjab, he wrote three booklets titled Kheti ki Pehli Kitab, Kheti ki Doosri Kita, and Kheti ki Teesri Kitab in Punjabi.

Sahni mentions in his memoirs titled Self-Revelations of an Octogenarian published as Ruchi Ram Sahni: A Memoir of Pre-Partition Punjab (OUP, 2017) that he experimented with organic farming on his own land before writing these manuals. Had the Punjab kept up the traditions set by people like Sahni, Sir Ganga Ram and Abdus Salam, the scientific landscape of Pakistan would have been quite different.

The writer has a PhD in history from the Quaid-i-Azam University, Islamabad. He heads the History Department at University of Sargodha. He has worked as a research fellow at Royal Holloway College, University of London. He can be reached at abrar.zahoor@hotmail.com. His X handle: @AbrarZahoor1