blog@Yantrajaal

  Why is 42  a special number? The number 42 is, in The Hitchhiker's Guide to the Galaxy by Douglas Adams, the "Answer to the Ultimate Question of Life, the Universe, and Everything", calculated by an enormous supercomputer named Deep Thought over a period of 7.5 million years. This slide deck  (with 42 slides) demonstrates a wide variety of SQL statements that should meet almost every common requirement faced by data scientists. The accompanying Google Colab Notebook will allow the user to install Postgres in a free VM and explore variations of these commands. Here is the full course outline for my brand new RDBMS course, complete with all slide decks and notebooks.    Happy New Year 2024

While India celebrates the success of Chandrayaan-3 in safely delivering the Vikram lander and the Pragyan rover to the surface of the Moon, it should not view this exercise as an end by itself but merely a means to an end. But what is that end goal that India should be looking for?  A lunar base of course, but first, why? History tells us that the famous Chinese mariner Zheng He carried out seven maritime missions (1405 - 1433) on behalf of the Ming emperor to different parts of East and South-East Asia right up to the Horn of Africa. The goal was to increase trade by 'showing the flag' and impressing the natives of distant lands with the maritime prowess of the Chinese navy and the wealth of products that were available in China. But the fatal flaw in this strategy was that he never established a Chinese colony anywhere. On the other hand, the European mariners who came a century later not only visited the same ports but immediately set up 'factories' or trading posts...

The stunning success of the Chandrayaan / Vikram / Pragyan mission opens up a world of possibilities for India on the Moon. The next logical step would be to set up a permanent base station - similar to Dakshin Gangotri in Antartica -- that would serve as a locus for the mining, manufacturing and other operations. The Indian engineering industry has extensive experience in these areas, but their expertise would have to be fine-tuned and optimised for the lunar environment. The single most significant difference from Earth bound operations would be the use of autonomous machines, or robots, to do most, if not all of the work. This is because supporting a human workforce in such a harsh environment would increase the cost of doing business to the point of becoming economically non-sustainable. But irrespective of what we mine, manufacture or otherwise process on an industrial scale on the Moon, what we would need first is a source of energy - abundant energy. While solar panels that trap...

Unlike Abrahamic religions, Sanatan Dharma is mature enough to handle both heresy and blasphemy, and this gives us the right and liberty to question certain perspectives that lie at the core of what is referred to as Hinduism. Of late, a certain minor operative of ISKCON has been very critical of Vivekananda and Ramakrishna but on enquiring further I realised the ISKCON boss himself, Prabhupada, had referred to both Vivekananda and Aurobindo as rascals. To understand this behaviour, I delved further and realised that what I was reading today was in fact bending back to what a school friend of mine had once told me: that the Bhagavad Gita reads like a marketing pitch -- believe in me or you are doomed. An image of a woman seen in the reflection on  the pupil of one eye of another woman. digital art. Many well-known and supposedly erudite people have sung paeans to the glory of the Gita that was delivered 'directly by God' on the battlefield of the Mahabharat. But it has some obv...

 

Nearly 100,000 years before the present era, when hominins (modern humans) were diverging away from hominids (the great apes) on the evolutionary graph, we come across multiple species of humans like neanderthal, cro magnon and denisovan sharing space on earth. But with the passage of time and changing circumstances,  all human species except cro magnon were eventually eliminated leaving only one species, now identified as  homo sapiens (latin : wise man) to inherit the planet. Closer in time, or just about 500 years ago, we observed how the arrival of European Christians in America eliminated the social and cultural constructs of the Inca / Maya civilisations that had existed there since the dawn of history.  In both cases, the coexistence of two competing societies resulted in either the extinction or a significant transformation of one and the eventual growth and dominance of the other. Where both have survived, one has become the dominant, as in the case of humans, wh...

 This year, there has been an explosive flowering of the Palash flower all across the Bengal-Jharkhand border. Starting right from Raniganj and Asansol and following the railway line through Dhanbad, Bokaro and Chandrapura we saw an incredible number of Palash trees in full bloom.  But the best was reserved for us at Muruguma near the Purulia Ranchi district border. Here we stayed at the Bon Polashi Eco Hut and the place really lived up to its name. Shukraburu Mountain Sagorjhora Irrigation Scheme Lake