The Twentieth Century – Science’s Last Hurrah?

THE 19th century ended with the promise that almost all the mysteries of the world wereover. Science, it was thought, had come close to fully understanding nature, with only a few odds and ends yet to be sorted out, such as Brownian motion and the laws of thermal radiation.
In a scant few years, the entire edifice of classical physics – its absolute knowledge and complete determinism – collapsed. Instead, we now have the uncertainty of the quantum world and the relativity of time and space.


If the collapse of certainty is the hallmark of science of the twentieth century, what is the likely change that can take place in the twenty-first? While crystal gazing is not generally a fruitful activity, I may be pardoned for doing it on the eve of the new century. I think we enter the new century questioning science — that science and technology not only opens up new vistas but also unimaginable destructive powers. Therefore, the headlong rush into the newest and the latest, needs to be tempered by larger social concerns and caution.


That unlocking secrets of nature does not necessarily produce only good, comes from the simple Einsteinian equation familiar now to school boys – energy (E) is equal mass (M) times speed of light (C) squared – E = MC2. This seemed to hold the promise of an inexhaustible source of energy, prompting people to believe in the 50’s that energy would soon become so plentiful that it need not be metered. The bomb was thought to be the misuse of science, while the right use would produce cheap energy. Instead, the bomb has become the reality, with cheap, easy nuclear energy besieged with very high costs and enormous difficulties.


Similarly, cracking the genetic code and now genetically modified foods – GM foods as it is now called – seems again to be fraught with unknown dangers, while delivering much less than promised. So also medicines and cures through genetic engineering, which seemed destined to wrought miracles but have again delivered little.


Thus, the twenty-first century will have to address the notion that fundamental advances in knowledge may produce little of technological relevance and therefore impact society only marginally.


In contrast, a marginal phenomenon in science may produce societal affects that are profound. The vacuum tubes, transistors and integrated circuits are successive technologies that have produced the electronic revolution. They all depend on non-linear electrical phenomenon. In the linear world of classical physics, if we apply a higher voltage to a resistance, the current flow increases proportionately. This is Ohm’s law, the basis of electrical engineering. However, for electronic devices, this does not hold good. Thus, the relation between voltage and current flow is non-linear. For example, no current may be generated in a semi-conductor device till we build a sufficient voltage; it may then clamp the current to a particular value. Incidentally, J. C. Bose has the first known patent of a semi-conductor device, developed as a part of his wireless experiments. None of these advances individually amount to major advances in knowledge. However, it is microelectronics that constitutes the basis of the information revolution that will shape the twenty-first century




To me, the developments discussed above are the defining events of the century. The demise of classical physics by the development of quantum mechanics and theory of relativity, cracking the genetic code and the development of computers are the most important events of the twentieth century.


Of course, communications technology, antibiotics in medicine, flying machines – all of these can also vie for a place in the sun. I believe however that none of them have the profound intellectual or technological impact of the above.


The theory of relativity demolished the Newtonian world of absolutes. No longer was there a fixed frame of reference in time and space to which every event and location could be related. Instead, any event or a point in space could be referenced only with respective to a specific observer. While this change may seem esoteric and of concern only to physicists, it gave rise to serious philosophical difficulties. For example, two events that seem to be concurrent from the view of one observer, may not be so as viewed by another observer. There is no true currency of events; they are all relative to the chosen frame of reference, namely the frame of reference of the observer.


Einstein’s special theory of relativity was proposed in 1905 and later extended to the general theory of relativity. The immediate result for everyday physics was small – the theory explained an anomaly in the orbit of planet Mercury. Why then is the theory of relativity so important? The impact of theory of relativity was on philosophy. Cartesian absolutes were now clouded by this intrusion of relativity, seen to be a fundamental property of nature. While philosophy had witnessed debates on the limits of knowledge devised by our senses – positivism — or about the objectivity of the world around us – idealism versus materialism — it now had to consider that the fundamental space-time co-ordinates of the world could themselves be defined differently for each observer.




As if this was not enough, the world of the atom was to deliver another blow to the deterministic world of classical physics. The quantum phenomena – the phenomena at themicro level – were found to be uncertain. Heisenberg’s uncertainty principle, which appears to have survived the theory of hidden variables, proposes that a particle in this micro-world has either a defined position or a known velocity, and we cannot know both simultaneously. It was also proposed that this was neither a measurement problem, nor due to hidden variables, but intrinsic to micro phenomena. Thus, the Schroedinger equations give us the measure of probability of finding a particle but not a definite prediction.


This probabilistic formulation of the quantum world destroyed the deterministic view of science. This view was that if we knew the initial state of a system accurately, we could predict all future states. This certainty now ended and physics has confronted uncertainty at the heart of this quantum world.


Remarkably enough, though the quantum world helps us to understand non-linear semi-conductors, quantum laws themselves are linear. Thus, the non-linearity of quantum phenomenon is manifest at the macro level of our everyday universe (or when the micro-world meets the macro-world). Thus quantum laws help us understand electronics, but not in designing any device. All electronic designing is still artisanal – all based on trial and error!




At the level of life sciences, undoubtedly the story of the century is cracking of the DNA code. There is no doubt that learning of the DNA structure — the code of life – would have happened without Crick and Watson, who provided the familiar double helix structure of the DNA. There was something sordid about Watson’s stealing experimental results from fellow scientist Rosalind Franklin, and later viciously caricaturing her in his book “the Double Helix”. Unlocking the code of life has now extended to mapping the human genome, and also genetic engineering, including cloning of Dolly, the sheep.


Genetic engineering is changing the natural arrangement of genes in organisms and splicing together of genes of even dis-similar species.


Some form of genetic engineering is always done by nature – mutations and evolution are nature’s genetic engineering. Plant and livestock breeders also do it all the time. The cardinal difference between these and the genetic engineering done today is that we are using genetic material from species that can not mate and reproduce in nature, and splicing them together.


Genetic engineering can splice the genetic material of bacteria that produces anti-pesticide toxin to cotton germ plasm, producing the pest resistant BT Cotton of Monsanto. The flip side of this is that such splicing can produce unforeseen effects. BT Cotton has virtually decimated the population of Monarch butterflies in US.


The life chain is so complex that its disturbance may have unforeseen consequences and requires much greater caution than what Monsanto is prepared to exercise.


Interestingly, it is the unheralded semi-conductors, discovered at the turn of the century, which is changing the entire culture of technology. No productive activity today is free from electronics and computers — whether the creative writer or the workman in a factory, the computer touches them equally. Not only that, the Internet or weaving together of myriads of computers in a world-wide web is harnessing the energies of literally millions, in providing a global pool of common knowledge. If the expert in public policy – scientific or otherwise – had a privileged position, this is crumbling today under the assault of the people who have pooled their resources through the web. If the printing press democratised knowledge and broke the stranglehold of the clergy on knowledge, the Internet spells the death of the expert as the voice of the establishment.


A review of the century is necessarily personal and idiosyncratic. So is my review here. I believe human greed will push science and technology beyond its safe envelope. The twenty-first century will regard with marvel the naivety of the scientists and the greed of global capital. Twentieth century may turn out be science’s last hurrah, as unbridled optimism of a youthful science gives way to wariness and caution of maturity. This may indeed be the century when science truly comes of age.