pp 1-3 January 2021 General Editorial
General Editorial on Publication Ethics
pp 5-8 January 2021 Editorial
pp 9-9 January 2021 Science Smiles
pp 13-31 January 2021 General Article
Rajesh Gopakumar Spenta R Wadia
Stephen Hawking, born on 8 January 1942, at Oxford in an academic family, had an early aptitude and inclination towards science. He studied physics and chemistry at the university in Oxford, though he seems not to have excelled as a student, instead spending much of his time at the college boat club! He went to Cambridge for his PhD hoping to study cosmology with Fred Hoyle, but instead was assigned to Dennis Sciama who proved to be an important influence on him. It was at this time that Hawking was diagnosed with ALS or Lou Gehrig’s disease – a degenerative motor neuronal disorder. Though he was given only a couple of years to live at age 22 or so, his disease progressed slower than predicted. Hawking overcame an initial depression to plunge fully into his research soon making a mark for himself, winning the prestigious Adams Prize in 1966, for his thesis work on singularities in Einstein’s theory of gravity. He remained at Cambridge as a Fellow of Caius and Gonville College for much of his research career, except for a stint as the Sherman Fairchild Distinguished Professor at Caltech, USA, from 1970 to 1975. He was elected at age 32 as a Fellow of the Royal Society of London and in 1979 appointed to the celebrated Lucasian Professorship of Mathematics (held by Newton, Babbage, Dirac and others) at Cambridge. He held this post till his retirement in 2009.
pp 33-46 January 2021 General Article
Recent Progress on the Black Hole Information Paradox: Computation of the Page Curve
We give a brief overview of the black hole information problem and describe qualitatively the recent research that shows that the von Neumann entropy of Hawking radiation follows the Page curve, and hence is consistent with unitary, information-preserving time evolution.
pp 47-60 January 2021 General Article
Of Light and Shadows: Raychaudhuri’s Equation, the Big Bang and Black Holes
Einstein’s genius and penetrating physical intuition led to the general theory of relativity, which incorporates gravity into the geometry of spacetime. However, the theory of general relativity leads to perspectives which go far beyond the vision of its creator. Many of these insights came to light only after Einstein’s death in 1955. These developments were due to a new breed of relativists, like Penrose, Hawking and Geroch, who approached the subject with a higher degree of math-ematical sophistication than earlier workers. Some of these insights were made possible because of work by Amal Kumar Raychaudhuri (AKR) who derived an equation which turned out to be a key ingredient in the singularity theorems of general relativity. This article explains AKR’s work in elementary terms.
pp 61-71 January 2021 General Article
Body Size Matters in the Lives of Organisms
Body size, arguably the most important attribute of all organisms in the living world, is a reliable predictor of their physiological rates and life-history attributes. Metabolic rates of all organisms ($MR$) are related directly to their body mass ($M$) as an allometric function $MR = \alpha M \frac{3}{4}$ (Kleiber’s rule). The high, mass-specific metabolic rates of small animals can be accounted for by their high surface area/volume ratios. The much-discussed ‘metabolic theory of ecology’ is essentially an expansion of Kleiber’s rule equation to include two additional metabolism-influencing factors—temperature and resource availability—with a more generalized quarter-power exponent. According to this theory, many physiological rates, life-history traits and ecological processes follow quarter-power scaling laws. Living organisms must also obey the laws of physics. The relative importance of different physical forces to the organisms living on land or in water is also dependent on their body size.
pp 73-87 January 2021 General Article
Priyadaranjan Ray: Contributions to Chemical Science
Prof. Priyadaranjan Ray’s contribution to inorganic chemistry and related disciplines is enormous. His work on the elucidation of valency and structure of coordination compounds through magnetic measurements, proposition of Ray–Dutt twist mechanism and the discovery of inner metallic complexes of higher than second-order made him internationally famous. He first reported the two ligand isomers of thiosulphate ion and designed several organic reagents for the detection and estimation of metal ions. Stabilization of unusual oxidation state of metal ions through coordination with suitable ligand was also his important work. Besides science, he was interested in its history. Scientific activities as well as a brief life-sketch of this Indian stalwart of science is summarized in this present endeavour.
pp 89-104 January 2021 General Article
This article explains the history and mathematics of Brownian motion.
pp 105-126 January 2021 Series Article
How to Design Experiments in Animal Behaviour: 16. Cutting-Edge Research at Trifling Cost
I have had multiple aims in writing this series of articles. My primary aim has been to show how simple and innovative experiments can be performed at almost no cost, by nearly anyone, to create significant new knowledge. The history of science shows that this is true in most areas of scientific research, albeit to varying degrees. I have focussed on the field of animal behaviour both because I am more familiar with this field than others, but also because, the field of animal behaviour is especially well-suited for such low-cost research. It has also been my aim, of course, to discuss the princi-ples of ethology (the scientific study of animal behaviour), through the medium of these experiments. My motivation in writing this series is to bring social prestige to low-cost research, make the practice of science more inclusive and democratic, and empower large numbers of people to become knowledge producers rather than merely remain knowledge consumers. The people I especially have in mind are, less-endowed sections of society, including, but not restricted to, under developed countries, marginalised institutions and individuals, students, the general public, amateurs, and all those with little or no access to large research grants and sophisti-cated laboratory facilities, for whatever reason.Note: Some passages in this article are reprinted from Suggested Readings [4, 5, 15 and 16].
pp 127-128 January 2021 Classroom
A Visual Proof: $e \leq A \leq B \Rightarrow AB > BA$
pp 129-132 January 2021 Book Review
Can Argumentation be Taught in School?
pp 133-156 January 2021 Classics
Particle Creation by Black Holes
pp 157-157 January 2021 Information and Announcements
pp 158-158 January 2021 Information and Announcements
pp 159-159 January 2021 Information and Announcements
pp 160-160 January 2021 Night Life
Current Issue
Volume 26 | Issue 1
January 2021
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