pp 1171-1174 September 2020 Editorial
pp 1175-1175 September 2020 Science Smiles
pp 1179-1184 September 2020 Article-in-a-Box
pp 1185-1195 September 2020 General Article
Since October 2019, Betelgeuse began to dim noticeably and by January 2020 its brightness had dropped by a factor of approximately 2.5, demoting it from the position of the top (apparent) brightest 11th star to the 21st! Astronomers were excited and thought of it as the lull before the storm, Betel-geuse was ready to go supernova!This article is aimed more as a case study where we show how this question was answered using scientiﬁc arguments and data. It will also highlight the importance of supernovae to human existence and give a brief discussion on the evolu-tion of massive stars.And also, answer the question!
pp 1197-1213 September 2020 General Article
Hydra, a freshwater diploblast, with a simple but deﬁned body plan, an organized nervous system, and the presence of stem cells, is one of the oldest model organisms used in biology. It exhibits many embryonic features even as an adult, a spectacular ability of regeneration, and lack of organismal aging. Hydra can provide insights into how complex animal forms evolved and is waiting to be better utilized in teaching.
pp 1215-1230 September 2020 General Article
How do neurons orchestrate behaviour? Let us trace our footsteps back to one of the ﬁrst hypotheses proposing an al-liance between the brain and behaviour. This article trace Donald Hebb’s life, and how, in the neurophysiology milieu of the 20th century, he revolutionized the way psychologists and neuroscientists viewed the brain, bringing a unifying concept of the mind with his publication of $The Organization of Behaviour$. In closing, the legacy of Hebb in the after-years of the monograph is discussed in the context of contemporary discoveries in the realm of neural plasticity and learning that revisit Hebbian concepts.
pp 1231-1239 September 2020 General Article
This article is an attempt to put together my experiences gath-ered over the last six years of teaching biology. Since joining as a research faculty, I have learnt that teaching is a tough but extremely rewarding (both scientiﬁcally and emotionally) activity when done the right way. As research institutions across India are increasingly focused on imparting quality ed-ucation, I consider it imperative that every researcher aims to be a good teacher. I have been striving to be one, but at this point, I am far from it. In this article, I share my opinions based on my personal experiences. These experiences have helped me improve my teaching, as well as, connect better with the students—in the class, as well as, in the laboratory.
pp 1241-1249 September 2020 General Article
The undergraduate student perception of inorganic chem-istry as routine and unimaginative was transformed by adopt-ing few innovative approaches in the pedagogy. This is pri-marily a reﬂection of my experiences in classroom teaching that is presented in this commentary. Fun-oriented, anal-ogy based and pragmatic approach was used to explain sim-ple concepts in inorganic chemistry. Laboratory demonstrations and exposure to understand research articles made the course more interesting. Selective examples of deﬁning classroom moments are presented in this reﬂective commentary. Framing questions in an animated, imaginative and unconventional style made students feel quite challenged and also experience the joy in learning. The introduction of group discussion as an evaluative component enhanced the soft skills of the students. The creative instinct in learning changed students’ perception of inorganic chemistry from an insipid to a highly engaging and captivating subject.
pp 1251-1260 September 2020 General Article
We revisit a problem faced by all programmers. Can one write a program that determines whether any given program is the shortest program? How does one prove that a given program is the shortest? After answering these questions, we discuss very brieﬂy the Kolmogorov complexity of a string of zero and one, which leads to a barrier on any axiomatic system, known as Chaitin’s barrier.
pp 1261-1281 September 2020 General Article
The simple textbook problem of a particle on a vertical, rotating hoop is analysed both in theory and through exper-iments. We begin by detailing out a somewhat generalised theory, where the eﬀect of dry friction as well as the possibility of a shift in the vertical axis of rotation are incorporated. The bifurcation curves (plots of the angular position of stability versus the angular frequency of rotation) are obtained for all cases (i.e. with and without friction and a shift of the axis). Thereafter we present the experimental set-up fabricated by us and elaborate on the various measurements performed. Finally, we demonstrate through our experiments how well the theoretical results on the bifurcation curves tally with the experimental ﬁndings. The match between theory and experiment is found to be reasonably satisfactory. We conclude by mentioning how various aspects of this simple problem as well as its generalisations and extensions, are linked with dif-ferent advanced areas of physics.
pp 1283-1286 September 2020 Classroom
De Broglie’s hypothesis of the dual nature of matter was conﬁrmed experimentally independently by Davisson-Germer and G. P. Thomson. But most of the textbooks (e.g. ) discuss Davisson–Germer experiment. In this article, G. P. Thomson’s experiment of electron diﬀraction is discussed.
pp 1287-1289 September 2020 Book Review
pp 1291-1306 September 2020 Classics
Kothari’s classic paper on the theory of pressure ionization showed that matter can be ionized at high pressure as a logical extension of Saha’s theory of thermal ionization to cold matter. Saha’s theory was applied to non-degenerate electron gas and Kothari considered non-relativistic degenerate electron gas subjected to high pressures, such as occurring in astrophysical objects under their own gravity. He used the virial theorem to predict the degree of ionization as a function of its density. It showed that (i) stellar material in the interiors of white dwarf stars should be fully ionized even at zero temperature, (ii) it is possible for hydrogen to go into a metallic state at high pressures as in the interior of Jupiter and Saturn, (iii) there exists a maximum radius of a non-relativistic degenerate electron gas system (cold body), the value being nearly that of Jupiter.
pp 1307-1307 September 2020 Information and Announcements
pp 1308-1308 September 2020 Information and Announcements
pp 1309-1309 September 2020 Birds in the Backyard
Volume 25 | Issue 10