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PRL Ka Amrut Vyakhyaan

Human Impact on Global Climate Change Over the Past Two Centuries: Use of Isotope-Tracing Techniques

Date
2023-07-19
Speaker
Prof. Mark Baskaran

Abstract

The human impact on global climate change over the past two centuries is unprecedented. An incredible growth of population, from 1.5 billion in 1900 to 7.9 billion today has led to an increase in energy consumption by more than 1000% over ~70 years to power the development. Never in the history of the Earth has such a drastic increase in the atmospheric CO2, from 296 ppm in 1900 to 423 ppm in 2023, took place; it is attributed to energy extraction from non-renewable resources (e.g., fossil fuel) contributing ~85% of total energy consumption. The ‘science of the changing environment’ is at the forefront of human endeavor and a significant (and increasing) fraction of the global GDP is currently being spent on addressing this science (e.g., increasing spatial extent of harmful algal blooms, ocean acidification, ever increasing number of micro-plastics in fresh and saltwater systems, weather-related catastrophic events, etc). Isotopes of key chemical elements have been widely utilized to identify and quantify recent environmental changes. In this talk, a set of case studies, illustrating global environmental changes in different regions of global oceans will be presented.

PEACE THROUGH EDUCATION IN NORTH-EAST INDIA<img src='/prl-eng/images/red.gif'>

Date
2023-06-14
Speaker
COL. CHRISTOPHER REGO (RETD.)
Venue
K R Ramanathan Auditorium, PRL Main Campus Ahmedabad

Abstract

Many parts of India’s North East have been plagued with insurgency and ethnic conflict for decades. This has cost the country heavily in terms of lives, livelihoods and development of this region. Importantly, given the threat posed by our aggressive northern neigbhour, this instability is severely impacting the security of this strategic limb. With the obvious linkage of lack of education and empowerment to the radicalization of youth and perpetuation of ethnic divisions, this talk of Peace through Education in Northeast India by Col Christopher Rego is about a sustainable solution to insurgency and conflict through his innovative approach executed through his organization Sunbird Trust.

FUTURE SPACE EXPLORATION – A PERSPECTIVE<img src='/prl-eng/images/red.gif'>

Date
2023-05-24
Speaker
Wg. Cdr. Rakesh Sharma, Ashoka Chakra
Venue
K R Ramanathan Auditorium, PRL Main Campus, Ahmedabad

Abstract

“The Human civilization is poised to recommence space exploration; this time, not to explore but to inhabit, first the Moon and later, perhaps, Mars. How should we plan for this fundamental shift in our space activity? Do we adopt the same paradigm as we have done thus far i.e., the initial explorer takes it all? Should our approach be exclusive or inclusive? Should we be going out there while continuing to retain our national identities or, as explorers from Planet Earth? Do we go forth by leveraging the advantage one or the other nation has by virtue of its better technological base or, do we go out as a civilization from Planet Earth that recognizes that Space is not the domain of any one nation, that all human activity in outer space must benefit humankind resident on Planet Earth, as has been mandated by the United Nations?”

Shocking waves – Healing touch!<img src='/prl-eng/images/red.gif'>

Date
2023-04-19
Speaker
Prof. Gopalan Jagadeesh
Venue
Online

Abstract

The phenomenon of “Shock Waves” has been historically associated with aerospace engineering and in particular with supersonic flight. Shock waves appear in nature, when different elements in a fluid approach one another with a velocity higher than the local speed of sound. These waves are also generated if massive energy dissipation takes place within ultra-short time in events like explosions. A number of methodologies/facilities to generate shock waves of requisite strength have been designed and indigenously built in the Laboratory for Hypersonic and Shockwave Research (LHSR) in Indian Institute of Science (IISc), Bangalore. Over the years, these facilities have facilitated very interesting interdisciplinary research programmes in IISc with participation of several faculty members from physics, chemistry, biology and materials engineering. Some of the novel techniques that will be discussed in this talk includes retractable aero-spikes, smart coatings, forward facing jets and concentrated energy deposition for reducing the aerodynamic drag around vehicles flying at hypersonic speeds. Concurrently, utilizing the remarkable ability of shock waves to instantaneously enhance the pressure and temperature in the propagating medium, several innovative shock wave assisted techniques have been developed in LHSR. These include non-intrusive needleless vaccine delivery, cell transformation, Wound healing, bio-film destruction, sandal oil extraction, polyphenol enrichment in tea, metal texture modification, and preservative impregnation in bamboo. A broad overview of the recent Transdisciplinary shock wave research and technology development activities at LHSR will be presented in this Colloquium.

Apollo to Artemis: The Science and Exploration of the Moon<img src='/prl-eng/images/red.gif'>

Date
2023-02-22
Speaker
Prof. Mahesh Anand
Venue
K R Ramanathan Auditorium, PRL Main Campus, Ahmedabad

Abstract

The Moon’s pull on our imagination is unrivalled, as best demonstrated by the Apollo programme. Fifty years on, humanity stands at the crossroads of technological advancement and scientific knowledge, ushering in a new era of human and robotic space exploration. Scientific discoveries relating to the history of water and other associated volatiles on and in the Moon have renewed global interest in lunar exploration. Thus, the Moon is becoming a favourite target for established and emerging space-faring nations and commercial entities. In addition to national pride and scientific curiosity, the renaissance in lunar exploration is also driven by an increased realisation of the Moon as a technology testbed for exploring more distant bodies such as Mars and asteroids. The possibility of utilising the Moon and its constituents as resources for sustaining an extended presence on its surface has heralded an era of 'New Space' by attracting private and commercial bodies towards lunar exploration, guided by scientific insights derived from continuing research on lunar samples. Our vision of the future sees a sustainable presence of humans based on the lunar surface. For this, the natural resources present there must be explored and utilised. The coming decades are likely to witness the realisation of Living on the Moon, enabled by research that is commonly termed lunar in situ resource utilisation (ISRU).

My Professional Forays- People, Challenges & Anecdotes<img src='/prl-eng/images/red.gif'>

Date
2023-01-30
Speaker
Dr. K. Kasturirangan
Venue
K R Ramanathan Auditorium, PRL Main Campus, Ahmedabad

Abstract

On the eve of the 75th Anniversary of PRL coming into being, I consider it my special privilege to be with all of you and share some of the memories that have left a permanent imprint on me. I am grateful to Prof Anil Bhardwaj and the present management of PRL, for inviting me to give a talk befitting this august occasion. I shall touch upon some interesting episodes of my research career at PRL, including working with Dr Vikram Sarabhai, its legendary Founder and being guided by such mentors like Prof P D Bhavasar and Prof N W Nerurkar. I started my forays into India’s Space Program thanks to the persuasive power of Vikram Sarabhai and in the next thirty years or so made a very interesting, challenging and most memorable journey working in satellites, applications, space science and overseeing the overall program in the final stages of my career in ISRO as its Chairman. A brief account of some of the related memories, that I hold from that period shall be narrated with particular focus on my unique association with my illustrious predecessor Chairmen - Vikram Sarabhai, MGK Menon, Satish Dhawan and UR Rao. Subsequent developments in my professional trajectory beyond space and some of the resulting excitements and challenges will be narrated as a part of my role as Member of Rajya Sabha, Member of Erstwhile Planning Commission and more recently, Chairman, National Education Policy Committee. To me, this totality of roles spread over nearly fifty years, prove to be an extraordinary journey in understanding the issues of development of this Nation, with its complexity, diversity and plurality. I owe the humble service that I could render for this Nation, to individuals, leaders of political systems, many institutions and the most crucial support that I received from my colleagues and well-wishers; on this historic occasion I remember all of them through this talk.

Vikram Sarabhai and Indian space programme<img src='/prl-eng/images/red.gif'>

Date
2023-01-05
Speaker
Shri A S Kiran Kumar
Venue
K R Ramanathan Auditorium, PRL Main Campus, Ahmedabad

Abstract

Vikram Sarabhai a man of many dimensions, an outstanding scientist deeply concerned about the country's need to provide science and technology based solutions to the problems faced by society and citizen's of a country which was grappling with governance as an independent nation after emerging from centuries of external rule. In the space programme one of his many dreams was to use national satellite programme to provide a better way of life to the 630000 villages of India. He had hoped by the research and development activities of the space programme that television would be available to 80% of India's population in ten years. This project was of special significance because by providing entertainment and instruction of high quality it would be possible to bring about a quantitative improvement in the richness of rural life. He often used to say that “I have a dream, a fantasy may be that we can leapfrog our way to development”. And over the years he showed his capacity to leapfrog many decades and translate many of his dreams into realities. Visualizing the ability of objects going beyond earth to provide solutions to the problems we faced and the use of emerging disruptive technology of space were indeed acts of great impact and the manner in which he facilitated its role out in the country needs to be remembered by us even as we complete 75 years of existence as independent India and further as we look at navigating through the 'Azadi ka Amrut mahotsav' and reach the landmark of 2047.

Galaxy evolution: The atomic hydrogen perspective<img src='/prl-eng/images/red.gif'>

Date
2022-12-20
Speaker
Prof. Jayaram Chengalur
Venue
ONLINE

Abstract

As galaxies evolve they convert their gas into stars. On a cosmic scale, it is well established that the star formation peaked about 10 billion years ago (redshifts ~2-3) and that the average star formation rate of the universe has declined sharply since then. Atomic Hydrogen is the primary fuel for star formation; stars form as the gas cools to become molecular hydrogen, which then cools further and collapses under self gravity. Understanding the evolution of the atomic hydrogen content of galaxies is hence important to understanding the evolution of the star formation rate with cosmic time. Unfortunately, because of the difficulties in detecting atomic hydrogen emission (via its best tracer, the 21 cm spectral line), until recently very little was known about the evolution of the gas content of star forming galaxies. The speaker will discuss results from ongoing atomic hydrogen surveys of star forming galaxies using the upgraded Giant Meterewave Radio Telescope (uGMRT) that have significantly added to our understanding of the evolution of the baryonic content of galaxies.

Propelled by quests: Gravitational wave science<img src='/prl-eng/images/red.gif'>

Date
2022-12-14
Speaker
Prof. Tarun Souradeep
Venue
ONLINE

Abstract

Scientific quests, especially grand ones, have always pushed the boundaries of scientific & technological capability that eventually has impacted our daily lives. Deeper recognition of this aspect of fundamental science would lead to its broader acceptance in any society and its nation. The talk offers but a glimpse of this primarily through quests that the speaker has been personally involved from India. Talk highlights technology that enabled the recent discovery of gravitational waves from astrophysical bodies with LIGO, or that required for the ongoing quest to discover primeval gravitational waves from the birth of our Universe.

Hydrogen bonded interactions: Pawns in the Game of Molecular Chess<img src='/prl-eng/images/red.gif'>

Date
2022-12-08
Speaker
Prof. K. S. Viswanathan
Venue
ONLINE

Abstract

Non-covalent interactions, particularly hydrogen bonded interactions, have been studied over the last many decades, as they have a profound influence on many chemical, physical and biochemical processes. These interactions are very weak and their study has been a challenge. Many cold-molecules techniques have been used for the study of these interactions. We will discuss the use of one of such techniques – matrix isolation infrared spectroscopy corroborated with electronic structure calculations. A few cases based on our studies will be presented to highlight the characteristics of this weak interaction.

Building Dakshin Gangotri at Antarctica: A Miracle<img src='/prl-eng/images/red.gif'>

Date
2022-11-30
Speaker
Dr. Harsh K. Gupta
Venue
ONLINE

Abstract

The 3rd Indian Scientific Expedition to Antarctica led by Dr. Harsh Gupta established India’s first wintering station “Dakshin Gangotri’ in a record time, during the Antarctic summer of 1983/84. This record remains unbeaten to this day. The talk recreates the atmosphere of excitement, challenge, and fierce determination to make the country proud, along with meticulous planning and execution, which enabled this ‘Miracle’ feat! Tireless industry was the antidote to briefly dampened spirits after the near fatal MI-8 helicopter crash 3 days after arriving at Antarctica. Imagine digging 1.5 meter deep over an area of 620 square meters for placing the raft foundation and building a double storied structure complete with heating, laboratories, snow melting tank, commissioning of three generators, fuel dump, living quarters for 12 wintering team members, setting up of a medical room, communication room, gymnasium, recreation room etc. in 60 days. Several days were lost due to white-outs and blizzards. The triumph of Dakshin Gangotri bears testimony to the commitment to scientific exploration, both the outstanding team and those who extended unconditional support. The well-illustrated book takes you through the magic journey of constructing and populating “Dakshin Gangotr

Addressing Indian Societal problems through Science, Technology and Innovation in post-Independent India<img src='/prl-eng/images/red.gif'>

Date
2022-11-22
Speaker
Dr. Shekhar C. Mande
Venue
ONLINE

Abstract

At the time of Independence in 1947, India's GDP was mere Rs. 2.7 lakh Crore, with very few education institutions, industry and means of social support. The societal challenges to uplift people out of poverty, provide adequate food, healthcare and jobs remained daunting. Under these circumstances, India adopted Science, Technology and Innovation as one the primary vehicles to address these challenges. Large infrastructure was created in the initial decades, appropriate global practices were adopted in agriculture, and several innovative technologies were developed. As a result, it is estimated that India lifted more than 400 million people out of poverty between 2005 and 2020 alone. Many of the challenges faced by the society required local technologies and local innovations. India's S&T community rose spectacularly to these challenges and found innovative solutions to each of them. Dr. Mande will highlight a few examples during his talk.

An enigmatic fluid flow inside the Sun: the Meridional Circulation<img src='/prl-eng/images/red.gif'>

Date
2022-11-16
Speaker
Prof. Arnab Rai Choudhuri
Venue
ONLINE

Abstract

On the solar surface, we find a continuous flow of material from the equator to the poles. To avoid material piling up at the poles, there has to be a back-flow somewhere underneath the solar surface, which is now mapped by helioseismology. This flow – known as the meridional circulation – plays an important role in the dynamo process producing the 11-year sunspot cycle. I shall discuss our present-day observational and theoretical understanding of this intriguing circulation. The theory of the meridional circulation is intimately connected with the theory of differential rotation and provides a clue about the formation of the near-surface shear layer. It is found that the meridional circulation becomes weaker at the time of the sunspot maximum. I shall present our recent work on modelling this theoretically.

Fusion and Plasma Research in India: Where are we, where are we going<img src='/prl-eng/images/red.gif'>

Date
2022-11-09
Speaker
Dr. Shashank Chaturvedi
Venue
ONLINE

Abstract

Research at IPR can be divided into a few broad areas. The first is the development and operation of nuclear fusion-related devices called tokamaks. The second is R&D targeted at the indigenous development of Fusion Reactor Technologies, which are essential for an indigenous programme aiming at power from Nuclear Fusion. The third is basic research in plasmas and related fields, including exploration of the physics of alternative fusion concepts. The fourth is the development of plasma technologies for Societal/Industrial benefit. This talk will provide a brief overview of the above activities along with the Roadmap for the future.

Technology & Science in Legal Realm<img src='/prl-eng/images/red.gif'>

Date
2022-11-02
Speaker
Justice Vikram Nath
Venue
ONLINE

Abstract

The vyakhyaan would broadly encompass 4 sub-topics of discussion which are as follows: Space Law in India: This shall include discussion on laws governing space industry in India, Draft Space Activities Bill of 2017, need for a defined and articulate space law in India in light of issuing concerning space debris and Indian Space Policy, 2022. Environmental Laws and Science: This sub-topic shall broadly talk about the need of environmental laws, major environmental legislations in the country, Constitutional provisions furthering environmental rights and provisions in Indian Penal Code, 1860 penalising environmental crimes. It would also highlight the landmark judgments by Indian judiciary concerning environmental rights. Role of Technology in India’s Judicial System: This shall start off with the need of technological intervention in Indian judicial system and would progress towards a discussion on the technological initiatives that have been taken up by the e-committee of Supreme Court and the future initiatives which are currently in the pipeline. It would also discuss the issues which arise due to interplay of technology and legal world and how we can combat such challenges. Data Privacy Law in India: This sub-section shall deal with the Right to Data Privacy in light of K.S. Puttaswamy judgment of the Supreme Court, need for a data protection law in today’s technological era and would briefly touch upon the Draft Data Protection Bill. The vyakhyaan would close with brief comments on the possibilities and avenues that artificial intelligence may open up for the legal world.

What Can We Do With a Quantum Liquid?<img src='/prl-eng/images/red.gif'>

Date
2022-10-26
Speaker
Prof. Anthony J. Leggett
Venue
ONLINE

Abstract

In this "Amrut Vayakhayan" we will present an elementary account of the behaviour of gases and liquids at very low temperatures where counter-intuitive quantum mechanical effects are important. The constituent particles exhibit wave like properties, and below a certain critical temperature they transition into a very special state of matter called quantum condensate which shows macroscopic quantum behaviour. Recent developments in this field will be surveyed.

Train 18/Vande Bharat Project, How to exploit the spirit of Atmanirbhar Bharat!<img src='/prl-eng/images/red.gif'>

Date
2022-10-19
Speaker
Shri Sudhanshu Mani
Venue
ONLINE

Abstract

Atmanirbhar Bharat is not merely about making India a factory of the world but to boost development of Indian products in the industrial sector. All stakeholders must commit their design work in India, preferably through our own R&D, Design ex-per

Nuclear Fusion: Indian Program, ITER Project & Beyond<img src='/prl-eng/images/red.gif'>

Date
2022-10-12
Speaker
Prof. Shishir Deshpande
Venue
ONLINE

Abstract

A very significant research effort around the world is about finding and perfecting new sources of energy – sources that are clean, safe and with easy access for everyone. A number of spin-offs too occur in such effort, generating additional, unforeseen benefits. Nuclear fusion is known to be the cause of star-fire and past few decades have seen a series of breakthroughs which makes it possible to create an energy source from thermonuclear fusion. Controlled thermonuclear fusion in the laboratory remains a powerful driver in basic and applied plasma research. It offers a potentially attractive solution to power generation due to abundance of fuel, inherent safety and especially since it is environmentally acceptable. Over many years of research, the toroidal plasmas have revealed many facets of stability, control, confinement and transport. The worldwide research has culminated in the dream project called International Thermonuclear Experimental Reactor (ITER). Here the ultimate test of burning plasmas will be carried out in a fusion reactor. ITER is being built in France with ‘in-kind’ commitments from its seven partners (China, EU, India, Japan, S. Korea, Russia and the US). In this talk, an overview is presented on how this field has evolved and how it has shaped our grand-challenge perspective, what lies next and what might the key players in our long-term energy-future.

SUN EARTH SYSTEM AND SPACE WEATHER: a historical approach-Physics<img src='/prl-eng/images/red.gif'>

Date
2022-10-06
Speaker
Dr. Christine Amory-Mazaudier
Venue
ONLINE

Abstract

The purpose of Space Weather is the systemic study of the Sun-Earth system, in order to determine the impact of solar events on the Earth’s electromagnetic environment. This talk proposes a new transdisciplinary approach of the Sun-Earth system using the universal physical process of the dynamo. The dynamo process is based on two important parameters of the different plasmas of the sun-earth system which are the motion and the magnetic field. There are four large-scale permanent dynamos in the Sun-Earth system: the solar dynamo, the earth dynamo, the solar wind-magnetosphere dynamo, and the ionospheric dynamo, known since many decades. These four dynamos are studied in different scientific disciplines. This transdisciplinary approach links all these dynamos in order to understand the variations of the Earth's electromagnetic environment which affects our new technologies as the one of GNSS (Global Navigation Satellite System) and as a consequence our daily life.

Space: the less explored dimension of light<img src='/prl-eng/images/red.gif'>

Date
2022-09-28
Speaker
Prof. Siddharth Ramachandran
Venue
ONLINE

Abstract

This talk will describe the propagation, control and manipulation of light that manifests spatial complexity. In free space and bulk media, such higher order eigenstates of light possess intriguing characteristics such as the ability to carry spin and orbital angular momentum and the ability to self-heal. Upon confinement, either by focusing them, or by guiding them in fibers, even more exotic behaviour, akin to spin-orbit interactions of confined electrons in atomic and molecular systems, is observed – light’s polarisation as well as phase and group velocities become dependent on the intrinsic as well as extrinsic geometric path that the light beam takes. Such attributes have spawned applications as diverse as super-resolution microscopy, deep-tissue imaging, DNA sorting, classical and quantum communications, remote sensing and directed-energy defence strategies. This talk will describe recent applications, after elucidating the fundamental phenomena that make singular light beams behave dramatically differently from commonly encountered, conventional, Gaussian-shaped beams of light.

Threat of the Sun and Superflares<img src='/prl-eng/images/red.gif'>

Date
2022-09-21
Speaker
Prof. Kazunari Shibata
Venue
ONLINE

Abstract

Recent development of space and ground-based observations of the Sun revealed that the solar corona and chromosphere are much more dynamic than had been thought, and are full of explosions such as flares, jets, and coronal mass ejections (CMEs). It has also been found that such vigorous activity of the Sun often led to disasters or troubles in modern society on the Earth, e.g., radio communication failure, blackout of the city, malfunction of artificial satellites, and so on. There is a possibility that astronauts may have radiation sickness because of strong radiation particles from solar flares. Hence the “space weather prediction” is an urgent issue for human beings especially for future space business and space travel. On the other hand, recent observations of Sun-like stars revealed occurrence of superflares (with energy 10 times more than the largest flares, i.e., 1033 - 4x1034 erg) with frequency once per a few 100 - a few 1000 years. In this talk, the speaker will introduce recent development of solar and stellar research on these subjects, and finally discuss the following questions: Can superflares occur on the Sun ? If superflares occur on the Sun, what would happen in our modern society ?

Other Worlds in the Cosmos? The Search for Planets Similar to our Earth and... perhaps Sheltering Life!<img src='/prl-eng/images/red.gif'>

Date
2022-09-14
Speaker
Prof. Michel Mayor
Venue
ONLINE

Abstract

“Do there exist many worlds, or is there but a single world? This is one of the most noble and exalted questions in the study of Nature.” - Albertus Magnus (circa 1200–1280) Are there other Worlds in the universe? Does life exist elsewhere in the cosmos? The technology of our time has made it possible to transform this dream of antiquity into a fascinating field of current astrophysics. Twenty-six years after the discovery of a first planet orbiting a star like our sun, a few thousand planetary systems have been discovered. These first discoveries revealed to us the astonishing diversity of these systems, very different from our solar system. After the euphoria of these first discoveries, the era of studying the atmospheres of exoplanets is now beginning. Fascinating, despite the enormous contrast between the luminosity of the star and that very weak, reflected by the planet, the analysis of the atmospheres begins and will benefit from space telescopes and giant telescopes on the ground (up to diameters of 39m). Does life exist in other places in the cosmos? - Vertiginous question - The analysis of planetary atmospheres may reveal biosignatures, these spectral characteristics induced by the development of life. Advances in spectroscopy studies of exoplanets make us think that the search for extraterrestrial life is possible.

The Sarasvati River and the Indus civilization<img src='/prl-eng/images/red.gif'>

Date
2022-08-31
Speaker
Prof. Michel Danino
Venue
ONLINE

Abstract

From the 1850s, European scholars identified the seasonal Ghaggar-Hakra bed with the lost Sarasvati of Vedic literature. This talk will present recent scientific investigations in the Sarasvati river’s basin, in particular, geological studies and the issues they have addressed, such as the Sutlej’s and the Yamuna’s contributions to the Sarasvati system, the existence of a mega-river and the age of its disappearance; a phase-wise evolution of the Sarasvati river system will be proposed. We will then revisit the oft-debated question of the river’s contribution to the Indus or Harappan civilization.

Seismological Research and Gujarat’s Initiative<img src='/prl-eng/images/red.gif'>

Date
2022-08-24
Speaker
Dr. Sumer Chopra
Venue
ONLINE

Abstract

The Indian landmass is strained due to its collision with the Eurasian landmass since historical times, resulting in the formation of great Himalaya mountain chain. The strain accumulation is of the order of 100 nanostrain/year at the Himalaya plate boundary, ~10 at Indo-Gangetic plains and ~1 in peninsular India. The strain accumulation results in earthquakes in different parts of India. In the last 200 years, the Indian region has experienced many devastated earthquakes like 1819 Kachchh (M7.8), 1897 Shillong (M8.3), 1905 Kangra (M7.8), 1934 Bihar-Nepal (M8.0), 1950 Assam (M8.6) and 2001 Bhuj (M7.6). The total deaths due to the earthquakes in Indian peninsula is around 34,000 in last three decades. The earthquakes cannot be stopped but its affect can be mitigated through close monitoring of earthquake activity through a network of seismic stations to understand the physics of earthquakes, assessment of seismic hazard and building earthquake resistant infrastructure. It involves a multi-disciplinary initiative comprising of seismological, geological, geophysical and geotechnical studies.

Science and the Challenges of Climate Change<img src='/prl-eng/images/red.gif'>

Date
2022-08-10
Speaker
Mr. Kartikeya Sarabhai
Venue
ONLINE

Abstract

Human activity influencing climate was recognized at the first Earth Summit in 1992 which led to the creation of the United Nations Framework Convention on Climate Change (UNFCCC). Since then, the policy makers have met over 26 COPs and innumerable other policy dialogues to mitigate this emerging challenge. The scientific community via IPCC has played a major role in channelising the work of researchers to better inform policy making processes, by quantifying vulnerabilities and impacts across various sectors. India and developing countries have many unique problems and opportunities, and much more research is needed for their transition towards a sustainable economy. Institutions such as PRL could play a lead role in driving research in universities and research institutions making Indian climate policy making and action programmes much more rooted in data and evidence-based research. It is essential that the research also focuses on strengthening the role of education in developing and implementing policies, as well as promoting behavior change.

Probing the Universe with radio waves : landmark achievements in India over the years<img src='/prl-eng/images/red.gif'>

Date
2022-07-27
Speaker
Prof. Yashwant Gupta
Venue
ONLINE

Abstract

The demonstration of how to transmit and receive radio waves, first done by Acharya J.C. Bose in 1895, led to the opening up of a new window to the Universe, namely Radio Astronomy, in the 1940s. India has built up a strong reputation in this new field, starting from a few years after becoming an independent nation. In this presentation, we will trace the fascinating story of Radio Astronomy, with special focus on the landmark achievements in India over the last 60 years or so, starting with the early developments by the pioneers, and stopping briefly at all the major milestones achieved in the country. Special emphasis will be on the major facilities for radio astronomy created in India, such as the GMRT. We will also look briefly at future prospects for this field, globally as well as in India.

Luck and Networking - how they can help you<img src='/prl-eng/images/red.gif'>

Date
2022-07-20
Speaker
Luis Miranda
Venue
ONLINE

Abstract

Luis, who has been involved with 4 startups - HDFC Bank, ChrysCapital, IDFC Private Equity and Indian School of Public Policy - will talk about the breaks he had in his life and how you can create your own luck and build your networks to give you your own breaks.

मेरी भाषा, मेरा देश<img src='/prl-eng/images/red.gif'>

Date
2022-07-13
Speaker
Shri Vishnu Pandya
Venue
ONLINE

Abstract

देश आत्मा है और उसकी अभिव्यक्ति भाषा है| एक हो या अनेक, भाषा बड़ी शक्ति होती है| व्यक्ति और समूह दोनों का शस्त्र और शास्त्र का निर्माण भाषा से होता है| अपना इतिहास, समाज दर्शन, तत्वदर्शन, अर्थ शास्त्र, विज्ञान, शिक्षा और साहित्य का संबंध देश और भाषा से जीतना मजबूत होगा इतना राष्ट्र श्रेष्ठ बनेगा.

The Circuits of Sensation: How We Perceive the World<img src='/prl-eng/images/red.gif'>

Date
2022-07-06
Speaker
Prof. Shubha Tole
Venue
ONLINE

Abstract

The world outside is brought to our brains by our five senses. We experience the world by processing information brought to our brains via sensory devices; we remember and learn from our experiences; we execute actions based on them. Proper functioning of this system requires that each brain structure is formed in its correct location during embryonic development and that the growth of nerve connectivity to and from each structure is properly organized. This setting up the hardware is an engineering challenge that needs to be reliably executed in order to produce a functioning brain. In this colloquium, we will examine the regulatory processes by which brain structures and circuits are created using the mouse embryo as a model system. In mice, the whiskers on the snout act as "fingers" to sense the environment, providing an ideal model system to examine how the circuitry underlying sensory resolution is created. We identified a central regulator of sensory circuit formation in the brain by examining a mutant mouse in which this circuitry is profoundly defective. This same regulator, transcription factor Lhx2, also plays a fundamental role in designing the "blueprint" of where specific structures are to form in the brain. The speaker will present this work in a manner accessible to a wide non-specialist audience and also bring out the approaches and techniques used to explore the early development of the brain.

Explore and Learn<img src='/prl-eng/images/red.gif'>

Date
2022-06-22
Speaker
Shri Atul Karwal
Venue
ONLINE

Abstract

This talk would revolve around various explorations of the world outside –the Everest Expedition and Cycle ride to Mt. Kailash and Mansarovar lake and sharing the learning from these explorations for self-awareness and self-evolution.

A Historical Journey to Discover the Mysteries of Air<img src='/prl-eng/images/red.gif'>

Date
2022-06-15
Speaker
Prof. Guy Brasseur
Venue
ONLINE

Abstract

The ancient Greeks, who based their view of the world on four elements (earth, water, fire, and air), considered air to be a neutral, inseparable, and weightless element. With the revival of the scientific method at the Renaissance, after a long period of obscurantism, substantial progress was made. The atmospheric pressure was measured, the first laws of hydrodynamics were established following Newton’s approach; the fundamentals for science-based weather forecasts were gradually developed. At the same time, the first steps were made to identify the chemical nature of air. The theory of “phlogiston” dominated the discussions between “pneumatic chemists.” Brilliant minds including Black, Becher, Stahl, Scheele, Cavendish, Priestley, and finally Lavoisier made the first experimental investigations that explained combustion and respiration. The 18th century with the chemical revolution initiated by Lavoisier, and the 19th century, with the discovery of ozone by Schönbein, highlighted the chemical complexity attached to air. The concept of “greenhouse gases” was introduced to explain climate change during the 20th century. Research since the 1950s emphasized the presence of a multitude of minor constituents and the role of the atmosphere in sustaining life. Since 1970, the atmosphere has been viewed as a photochemical reactor. Today, air pollution has become a crucial problem with severe detrimental impacts on people’s health. Space observations, surface measurements, and modeling are tools that should help us to provide pure air to all citizens of the world.

Role of Plate Tectonics and Climate in the Evolution of Tropical Angiosperms: Evidence from Indian Fossil Records<img src='/prl-eng/images/red.gif'/>

Date
2022-06-08
Speaker
Dr. (Mrs.) Vandana Prasad
Venue
ONLINE

Abstract

Angiosperms are the most dominant plant community and represented in most ecosystems of the world. Tracing the evolution of angiosperms is arguably one of the most challenging and relevant issues in plant evolution. Angiosperms appeared during early Cretaceous, rapidly diversified and dominated the Earth’s terrestrial ecosystem by the Late Cretaceous. The Indian plate, after its separation from the Gondwana land, drifted towards the north but remained below the equatorial zone in the southern hemisphere during the Late Cretaceous. The Late Cretaceous infra- and intertrappean sedimentary successions from central India as well as the early Paleogene lignite successions from Kutch, Cambay and Rajasthan, western India, yielded a large number of tropical angiosperm fossils. Many of these fossils show similarity with the plants of the present-day tropical rain forests of Southern Western Ghats, India, Southeast Asia, evergreen vegetation of Africa, Madagascar, and South America. This provides clues regarding the role of plate tectonics and deep time climate change in the evolution, expansion, and dispersal of tropical angiosperms. An integrated study of morphological characters of the fossil pollen and the nearest living relatives (extant species) of the tropical angiosperms, along with molecular data of extant species are now being used under a phylogenetic framework to reconstruct the paleobiogeographic history of tropical angiosperms.

Living Beyond 100 Years - Myth or Truth?<img src='/prl-eng/images/red.gif'/>

Date
2022-05-25
Speaker
Dr. Parthiv Mehta
Venue
ONLINE

Abstract

I will be speaking on "Living Beyond 100 Years - Myth or Truth?" - an interesting topic for NON-MEDICAL attendees - wherein we shall connect with understanding of the human body - some amazing facts. Further we will take up the process of aging, factors affecting and ways to reduce that process. We shall also discuss the process of occurrence of disease and how best can we enhance recovery from it.

Infrared eyes: Exploring the solar system using infrared instruments<img src='/prl-eng/images/red.gif'/>

Date
2022-05-18
Speaker
Prof. Philip R. Christensen
Venue
ONLINE

Abstract

Thermal infrared observations have made significant contributions to planetary science over the past 50 years. Infrared spectroscopy has shed light on the composition of planetary surfaces and atmospheres, and thermal radiometry has provided great detail on the physical properties of planetary regoliths and their formation processes. Infrared instruments have been on virtually every planetary spacecraft, and these instruments have improved steadily over the past three decades. A great deal has been learned about the geology of Mars from a suite of thermal infrared instruments beginning with Mariner 6/7/9 and Viking, and continuing through Mars Global Surveyor, the Mars Exploration Rovers, and Mars Odyssey. Derivatives of these instruments have studied the asteroid Bennu on OSIRIS-Rex, Mars on the UAE Hope Mars mission, and are on the way to the Trojan asteroids on the Lucy mission. This talk will discuss some of the major discoveries that have come from these data and what we’ve learned from them about planetary processes and geology over the past 40 years – and will provide a few thoughts on the future of planetary exploration using thermal infrared observations.

41_PRL ma Amrut Vyakhyaan_Next Generation Species Specific and Eco Friendly Antibiotics and thoughts about the origin of life<img src='/prl-eng/images/red.gif'/>

Date
2022-05-11
Speaker
Prof. Ada Yonath
Venue
ONLINE

Abstract

Resistance to antibiotics is a severe problem in contemporary medicine. Many antibiotics inhibit protein biosynthesis by hampering the ribosome function. Structures of bacterial ribosomes in complex with these antibiotics illuminated common pathways of antibiotics inhibitory action. Structures of multi-resistant pathogenic bacterium revealed their novel structural motifs and led to the design of antibiotics with desired properties that can be optimized in terms of their chemical properties, toxicity and penetration, alongside species-specificity, thus preserving the microbiome. They can also be optimized for bio degradability, thus reducing the ecological hazards caused by the spread of the current antibiotics’ non-degradable metabolites. The site for peptide bond formation is located within an almost fully conserved internal region made exclusively of RNA. The high conservation of this region implies its existence irrespective of environmental conditions and indicates that it may represent an ancient RNA machine, which could be the kernel around which life originated. A lab constructs according to this pocket were shown to possess catalytic capabilities in peptide bond formations. Thus indicating that a molecular prebiotic bonding entity is still functioning in all living cells of all organisms.

The Cold Universe: A Journey to our Cosmic Origins<img src='/prl-eng/images/red.gif'/>

Date
2022-05-04
Speaker
Dr. Pierre Cox
Venue
ONLINE

Abstract

"In this review, I will present some of the major recent observational results obtained on the so-called cold universe, spanning the range from proto-planetary systems to the most luminous star-forming galaxies in the early universe. These results have been made possible in the last decade due to the increased capabilities offered by recent facilities operating in the sub/millimetre, most notably ALMA & NOEMA. I will highlight some of the fundamental questions that have been resolved and others that haven't been answered yet and explore how future enhancements or new observatories will help make further significant progress in our understanding on how stars, planets and galaxies form and evolve."

The ozone layer, its science, and its policies<img src='/prl-eng/images/red.gif'/>

Date
2022-04-20
Speaker
Prof. A.R. Ravishankara
Venue
ONLINE

Abstract

Ozone is arguably one of the essential molecules in the Earth's atmosphere- it protects the surface from the harsh UV solar radiation, is a climate gas, and is an air pollutant at the surface. The ozone layer, a region in the stratosphere where the ozone abundances are the largest in the atmosphere, is affected by human emissions. Since Chapman explained the existence of this layer in the 1930s, the understanding of the science in this layer has grown immensely. The depletion of this layer by ozone-depleting substances, used chiefly for refrigeration and air conditioning, led to the first universally ratified Montreal Protocol. The story of the ozone layer cannot be separated from either the substances that cause its depletion or the unexpected consequences of our efforts to protect it. The speaker will briefly summarize the story of the ozone layer, the consequences of substitutes for ozone-depleting substances (ODS), and the role of ODS in both ozone and climate. The speaker will show how the ozone layer issue is not a "solved" one, highlight why humanity needs to shepherd it through to its original state, if possible, and the next steps in this overarching issue. The speaker will finally discuss how the ozone layer science is evaluated and presented to the policy and decision-makers and touch on the considerations by policymakers in making their decisions.

ASTRO 3D<img src='/prl-eng/images/red.gif'/>

Date
2022-04-13
Speaker
Prof. Lisa Jennifer Kewley
Venue
ONLINE

Abstract

The ARC Centre of Excellence for All Sky Astrophysics in 3 Dimensions (ASTRO 3D) is a $40M Centre of Excellence, which is producing a comprehensive picture of the accumulation of mass, angular momentum, and the chemical elements from the first stars, to (and including) the Milky Way. Our surveys include the measurement of the power spectrum at the Epoch of Reionization with the Murchison Widefield Array, large HI surveys with the Square Kilometre Array Pathfinder, the ongoing Australian optical integral field surveys of 105 galaxies, a large galaxy evolution program combining HST, Keck, and ESO spectroscopy of galaxies from z=6 to z=0.5, and the major Australian Galactic Archaeology program to track the chemical history and accretion history of our Milky Way using the Anglo Australian Telescope. “I will describe the recent discoveries made in ASTRO 3D, our preparation for JWST spectral analysis, as well as providing an update on our ambitious equity and diversity programs, and our nationwide education and public outreach programs.”

Uttar Pradesh Metro: Building Modern Urban Transport Systems for the Changing Needs of the Cities: Challenges and Lessons Learnt<img src='/prl-eng/images/red.gif'/>

Date
2022-04-06
Speaker
Shri Kumar Keshav
Venue
ONLINE

Abstract

Shri Kumar Keshav, Managing Director, Uttar Pradesh Metro Rail Corporation (UPMRC) had led a team of professionals for the successful completion of 23 Km long North-South Corridor of Lucknow Metro Project Phase-1A. This project had been completed in a stipulated time frame of 4½ years which was 36 days ahead of the scheduled time. Thereby, this project achieved the distinction of being the fastest constructed Metro project in the country. Shri Kumar Keshav is an officer originally belonging to the Indian Railway Service of Engineers. He is a gold-medallist from IIT- Kanpur (MTech) and IIT-Roorkee (B.E.). He took over as Managing Director of the company on 18th August 2014 and soon commenced the work on 27th September 2014. Prior to that, he had a long tenure of more than ten years in the Delhi Metro Rail Corporation and contributed to the successful implementation of Phase-I and Phase-II of the Delhi Metro project. After leaving Delhi Metro in April 2012 Kumar Keshav holds the credit for leading the prestigious International Heavy Haul Rail Project in Queensland, Australia as Project Director-Rail. As regards to Lucknow Metro, it is a dream project of the people of Uttar Pradesh that had been realized by him ahead of the scheduled time. UPMRC has demonstrated its strength in project implementation of a highly complex project keeping in consideration the best international safety standards and quality parameters. UPMRC has been assigned two metro projects in two important cities of Uttar Pradesh namely Kanpur and Agra. The Kanpur Metro’s 9 KM priority corridor was completed in a record time of 2 Year 1.5 Months. Following the legacy of timely completion of metro projects, Kanpur Metro’s priority corridor now holds the distinctive feat of being the fastest constructed project in the country. Its revenue operations were inaugurated in the auspicious presence of Honourable PM Shri Narendra Modi and CM Yogi Adityanath on 28th December 2021. Both the metro projects are being executed at a fast pace under the dynamic leadership of Shri Kumar Keshav.

Quantum entanglement at all distances.<img src='/prl-eng/images/red.gif'/>

Date
2022-03-30
Speaker
Prof. Subir Sachdev
Venue
ONLINE

Abstract

Entanglement is the strangest feature of quantum theory, often dubbed ''spooky action at a distance''. Quantum entanglement can occur on a macroscopic scale with trillions of electrons, leading to novel superconductors which can conduct electricity without resistance even at relatively high temperatures. These superconductors also display a ‘strange metal’ regime in which individual electrons lose their identity. Related entanglement structures arise across the horizon of a black hole, and give rise to Hawking’s quantum paradox. “I will introduce and describe these long-standing problems in two very different fields of physics, and review progress in resolving them using insights from the Sachdev-Ye-Kitaev model.

Quark-Gluon Plasma: the perfect and most vortical fluid<img src='/prl-eng/images/red.gif'/>

Date
2022-03-23
Speaker
Prof. Bedangadas Mohanty
Venue
ONLINE

Abstract

The fundamental constituents of visible matter are quarks, gluons, and leptons. The quarks and gluons are not found to exist in a free state in nature. They are confined inside particles called hadrons. However, they were believed to be in a free state in the micro-second old Universe. We will discuss the formation of such a primordial matter of de-confined quarks and gluons in the laboratory and some of its interesting properties.

Open Access in Astronomy<img src='/prl-eng/images/red.gif'/>

Date
2022-03-16
Speaker
Ms. Uta Grothkopf
Venue
ONLINE

Abstract

Scholarly communication is undergoing major changes, aiming at more transparent and equitable practices that allow researchers to access, reproduce, and reuse existing scientific findings. This is often referred to as Open Science. An essential component in this movement is Open Access (OA) publishing. In this colloquium, we will explore what Open Access really means, how it has been received within the astronomy community, and which challenges are resulting from its implementation. The shift towards Open Access provides a unique opportunity to build a fair and inclusive publishing landscape. We will look at the role librarians play in this process, and emphasise the importance of collaboration within the research community at large.

Sport - An Integral component of Nation building<img src='/prl-eng/images/red.gif'/>

Date
2022-03-09
Speaker
Ms. Ashwini Nachappa
Venue
ONLINE

Abstract

The feeling of nationalism is indispensable to the idea of nation-building. Apart from religion, sports is the only common thread that binds people together and helps in developing a feeling of patriotism and unity that can counter the ills of society and the world. Sport encompasses social, political, cultural and economic aspects and therefore understanding the significance of sport is crucial. “Sharing my mantras of my experience on the track that has stood me in life and continues to be my guide.”

Ultra-violet Imaging Telescope and beyond<img src='/prl-eng/images/red.gif'/>

Date
2022-03-02
Speaker
Dr. Annapurni Subramaniam
Venue
ONLINE

Abstract

The Ultra-violet imaging Telescope (UVIT) is one of the instruments on the first Indian space observatory, AstroSat. In this talk the salient features of UVIT and some recent science results from it will be presented. This talk will also discuss the next-generation UV-optical space mission, INSIST, that is in the planning.

Human Space Program - challenges and strategies (29 PRL ka Amrut Vyakhyaan)<img src='/prl-eng/images/red.gif'/>

Date
2022-02-16
Speaker
Dr. V. R. Lalithambika
Venue
ONLINE

Abstract

Drivers for space exploration have conventionally been space science and human spaceflight. India’s first experience of human spaceflight came through the collaborative venture with USSR for the mission to Salyut 7, which has given both tangible and intangible benefits. With extensive experience in conventional spacecraft missions, we are now on the cusp of embarking upon our own human space program. The talk highlights the challenges involved in crewed space exploration and the various developments needed in the technological, and the human centric domains needed to make human space flight a reality. The mission related challenges in the launch, orbital and crew return phases are also discussed in detail.

Human Space Program - challenges and strategies<img src='/prl-eng/images/red.gif'/>

Date
2022-02-16
Speaker
Dr. V. R. Lalithambika
Venue
ONLINE

Abstract

Drivers for space exploration have conventionally been space science and human spaceflight. India’s first experience of human spaceflight came through the collaborative venture with USSR for the mission to Salyut 7, which has given both tangible and intangible benefits. With extensive experience in conventional spacecraft missions, we are now on the cusp of embarking upon our own human space program. The talk highlights the challenges involved in crewed space exploration and the various developments needed in the technological, and the human centric domains needed to make human space flight a reality. The mission related challenges in the launch, orbital and crew return phases are also discussed in detail.

Prevention is Health, and Wealth<img src='/prl-eng/images/red.gif'/>

Date
2022-02-09
Speaker
Dr. Gagandeep Kang, FRS
Venue
ONLINE

Abstract

Vaccines and vaccination have made a fundamental contribution to healthcare, decreasing, controlling and wiping out disease. These health effects translate to positive economic outcomes for individuals, healthcare systems and to society. However, the damage and consequences of diseases are rapidly forgotten, when the diseases are not seen in large number. Further, the full benefits of vaccines are not recognised and they are often undervalued and/or underused. Poorer countries think they cannot afford them, though new vaccines or increased vaccination coverage could improve the health of the population. Understanding the full value and potential impact of vaccines is critical to public health.

The oceanic geochemistry of the transition metals: tools to quantify the history of the oxygenation of the surface Earth<img src='/prl-eng/images/red.gif'/>

Date
2022-02-02
Speaker
Prof. Derek Vance
Venue
ONLINE

Abstract

The progressive oxygenation of the surface Earth is a planetary-scale process that is intimately linked to the evolution of the Earth’s biosphere. It involves a history that is characterised by long periods of stability, often accompanied by evolutionary stasis, punctuated by periods of rapid change. The first significant O2 likely appeared in the atmosphere during the first half of Earth history, made possible by the evolution of oxygenic photosynthesis. However, the much higher levels of surface Earth O2 required to oxygenate the oceans came much later, contributing to a complex array of drivers that led to the appearance of the first complex multi-cellular life close to the Precambrian-Cambrian boundary. There is an emerging consensus that the deep oceans did not emerge from anoxia (no dissolved O2) until well after this, towards the end of the Paleozoic Era. Many geochemical tools have been used to document this outline history, as well as many of the details within it. This talk will focus on a relatively new set of tools, some still emerging, some relatively mature, involving the geochemistry and isotope geochemistry of the transition metals. The solution chemistry of these metals in seawater, their speciation, solubility, and isotope transformations, is often controlled, either directly or indirectly, by redox-related processes. The group at ETH Zürich has helped to pioneer these tools, with an emphasis on a deep and comprehensive understanding of the modern processes that control their oceanic budgets, their cycling within the water column, and their loss from the seawater solution to sediments. It is only with this detailed mechanistic understanding of the controlling processes, that applications to Earth history can be robust. This talk will review this modern developmental work, and introduce some key applications to the study of the oxygenation of the oceans.

Squeezed light from abstraction to real-life applications: sensing and imaging well beyond standard quantum limit

Date
2022-01-19
Speaker
Prof. Girish S. Agarwal
Venue
ONLINE

Abstract

Quantum technologies are leading to the next revolution in communication, computing, information processing and in understanding large complex systems. This revolution will largely depend on unprecedented resolution, speed, and precision. An important beneficiary of quantum technologies would be quantum sensing and imaging. The development of novel paradigms in those fields are important, since they are likely to impact all fields of science and particularly biology. Classical sensing is very efficient down to a certain point, where stability and noise start impairing measurements. Sensing below that point (i.e., the standard quantum limit (SQL)), requires sensitivities that can only be produced with quantum light. Considerable theoretical work on quantum light was done in seventies and eighties, however, it is only in last two decades many real-life applications have started emerging leading to extensive activity all over the world. Both two-mode squeezed light and entangled photon pairs are ideal sources for producing super sensitivity in metrology. In the laboratory, we produce narrow band twin beam of squeezed light with about 6.8dB intensity difference squeezing and we are using such a source for a variety of sensing, imaging and novel non-linear spectroscopic applications which eventually would lead to highly sensitive Bio imaging. This talk will describe how the abstract theoretical developments are leading to new practical paradigms in sensing and imaging.

Societal and Economic Impacts of Space Weather<img src='/prl-eng/images/red.gif'/>

Date
2022-01-12
Speaker
Prof. Daniel N. Baker
Venue
ONLINE

Abstract

This talk describes space weather impacts and their economic and societal costs. Modern technological society is characterized by a complex set of interdependencies among its critical infrastructures. These are vulnerable to the effects of intense geomagnetic storms and solar storms. Strong currents flowing in the ionosphere can disrupt and damage Earth-based electric power grids and contribute to the accelerated corrosion of oil and gas pipelines. Magnetic storm-driven ionospheric disturbances interfere with high-frequency radio communications and navigation signals from Global Positioning System (GPS) satellites. Exposure of spacecraft to solar particles and radiation belt enhancements can cause temporary operational anomalies, damage critical electronics, degrade solar arrays, and blind optical systems such as imagers and star trackers. Moreover, intense solar particle events present a significant radiation hazard for astronauts during the high-latitude segment of the International Space Station (ISS) orbit as well as for future human explorers of the Moon and Mars. In addition to such direct effects as spacecraft anomalies or power grid outages, a thorough assessment of the impact of space weather events on present-day society must include the collateral effects of space-weather-driven technology failures. For example, polar cap absorption events due to solar particles can degrade – and, during severe events, completely black out – radio communications along transpolar aviation routes. A complete picture of the socioeconomic impact of space weather must include both direct, as well as collateral, effects of space-weather-driven technology failures on dependent infrastructures and services. It is also imperative that we—as a technological society—develop a truly operational space weather observing and modeling system in which the benefits of accurate forecasts are clearly established.

Organic Matter in the Universe<img src='/prl-eng/images/red.gif'/>

Date
2022-01-05
Speaker
Prof. Sun Kwok
Venue
ONLINE

Abstract

Recent observational and experimental evidence for the presence of complex organics in space is reviewed. Remote astronomical observations have detected over 200 gas-phase molecules through their rotational and vibrational transitions. Many classes of organic molecules are represented in this list, including some precursors to biological molecules. In the Solar System, almost all biologically relevant molecules can be found in the soluble component of carbonaceous meteorites. Complex organics of amorphous structures are present in the insoluble component of meteorites. Several unidentified astronomical spectral phenomena observed in the interstellar medium are likely to have originated from complex organics. The observation of these spectral features in distant galaxies suggests that organic synthesis had already taken place during the early epochs of the Universe. In this talk, we will discuss the chemical structures and possible origin of these organics. Specifically, we discuss the possible link between Solar System organics and the complex organics synthesized by stars during the last phases of stellar evolution. Implications of extraterrestrial organics on the origin of life on Earth and the possibility of existence of primordial organics on Earth will also be discussed.

From P. C. Ray to the present: Chemistry in Action<img src='/prl-eng/images/red.gif'/>

Date
2021-12-29
Speaker
Prof. V. Chandrasekhar
Venue
ONLINE

Abstract

We will trace the history of modern chemistry in India through the life and works of Acharya Prafulla Chandra Ray. Although India had a rich tradition in metallurgy and medicine, it was Acharya Ray who set up the first modern Chemistry School in the country. Among his students include famous physicists, S. N. Bose and M. Saha. Acharya Ray is extremely well known for his work on mercurous nitrite. But he did much more. He worked on diverse topics ranging from inorganic chemistry to some aspects of organic chemistry. He was conscious of the role of science in the development of industry. He set up the first chemical industry in the country, the Bengal Pharmaceuticals, and Chemicals. Acharya Ray was also a great Nationalist and Philanthropist. He left an indelible impression on many of his colleagues and the younger generation. We will also look at the development of chemistry post-Indian independence and will look at some representative Indian contributions. Finally, we will also examine how chemistry has contributed to the country’s economy.

Future Colliders

Date
2021-12-15
Speaker
Prof. Sreerup Raychaudhuri
Venue
ONLINE

Abstract

The runaway success of the Standard Model of particle physics has largely been due to a succession of beautiful experiments carried out at colliding-beam machines, or colliders. The most important of them, the LHC at CERN, has been running since 2009 and it discovered the Higgs boson in 2012. However, the LHC now faces a midlife crisis, since the last seven years have been singularly barren of new discoveries. Particle physicists are, therefore, already planning for the next generation of colliders, of even higher energy, which may lead us to a deeper understanding of Nature than the Standard Model affords. This talk will carry out a broad survey of some of these plans and the issues involved.

Shedding light on the Dark Matter in the Universe

Date
2021-12-08
Speaker
Prof. Rohini Godbole
Venue
ONLINE

Abstract

This talk will discuss one of the next frontiers to be crossed in the everlasting march towards unravelling the mysteries of nature, viz. the issue of Dark Matter (DM) in the Universe. In this context this talk will discuss about the observations that compel the scientists to believe that it exists and also explore its connection with accepted theories of particle physics. It will then discuss about the various ways to probe its nature and properties at the Large Hadron Collider (LHC), the future electron positron colliders like the ILC as well as other experiments happening deep underground. In the last part of the talk some research work will be touched upon that the speaker has been engaged in over the last few years in the context of the Supersymmetric Dark Matter, the lightest supersymmetric particle, LSP.

The Development of the East Asian Observatory

Date
2021-12-01
Speaker
Prof. Paul Ho

Abstract

The East Asian Observatory (EAO) was established in 2015 in order to promote the collaboration and the construction of large scale facilities in the East Asian regions. Our first project was to take over the operations of the James Clerk Maxwell Telescope on Mauna Kea in Hawaii. After seven years of very successful operations, we have a robust community of astronomers in the East Asian region which are collaborating on a variety of projects. While the original partners included the key observatories in Japan, China, Korea, and Taiwan, we now have a new partner from Thailand, while Vietnam, Indonesia, and Malaysia are in Observer status. This talk will report on the latest status of the EAO, and we invite India to join in our collaborations.

The Sun's Magnetic Field and Global Climate Change

Date
2021-11-17
Speaker
Prof. Sami K. Solanki
Venue
ONLINE

Abstract

The Sun is a restless star. It shows a wide variety of transient or active phenomena, such as dark sunspots, the continuously changing hot corona, energetic flares and immense coronal mass ejections, together with the associated output of energetic radiation and particles. The single quantity that is responsible for the continuing unrest of the Sun is its tangled and dynamic magnetic field. It produces these and many more fascinating phenomena, including variations in the Sun's radiative output or irradiance, which has been invoked as a source of solar influence on the Earth's climate. After an introduction to the Sun and its magnetic field, a short history of solar activity will be given and how that relates to the changing climate on Earth. Finally, the question is considered to which extent the Sun is responsible for the global warming seen in the last century.

Opportunities and Challenges beyond Mangalyaan in Interplanetary Missions and Planetary Protection Measures

Date
2021-11-03
Speaker
Prof. V. Adimurthy
Venue
ONLINE

Abstract

With the path breaking background of Chandrayaan and Mangalyaan missions, exciting possibilities of space exploration are in the offing in understanding the infinitude of the universe. In the domain of earth orbital, lunar and interplanetary missions, many new and innovative ideas are introduced in the recent decades. Future space endeavors will give us an excellent platform to enhance the quality of life and environment. However, increased space activities lead us to new issues, like the need to manage the detrimental effects of space debris. It is also recognized that there is a small but definite probability of large near-Earth asteroids (NEAs) impacting our planet. Today’s technology is mature enough for formulating suitable mitigation measures to avert a NEA impact catastrophe should such a need arise. This talk gives an overview of some of these exciting future technologies and scientific possibilities. These challenges are sure to inspire and occupy new generations of Indian students, scientists, engineers, educators, legal experts and administrators.

What are exoplanets made of? Molecular line lists to aid the characterisation of exoplanets.

Date
2021-10-27
Speaker
Prof. Jonathan Tennyson
Venue
ONLINE

Abstract

Over the last two decades thousands of exoplanets have been discovered and we now know that essentially every star supports a planetary system. Interest is therefore turning to characterising these planets: understanding what they are made of, how they formed and, of course, if any of them are capable of supporting life. This can only be achieve using spectroscopic observations, laboratory data and detailed models. The ExoMol project which runs from my group at UCL is dedicated to providing the spectroscopic data needed to characterise exoplanets. This talk will describe the methods we use to provide these data, the progress in understanding the composition of exoplanets and the prospects for doing this better in the near future.

Earth System Science for Socio-Economic Benefits

Date
2021-10-20
Speaker
Dr. M. Rajeevan
Venue
ONLINE

Abstract

Earth System Science considers interactions between the Earth’s spheres, Atmosphere, Hydrosphere, Cryosphere, Lithosphere, and the Biosphere, as well as the impact of human societies on these components. Earth System Science Services include weather and climate, Ocean, Coastal State and Seismological Services. Ministry of Earth Sciences provides these services for the benefit of the country through its scientific programs. During the past 8-10 years, Government had invested in improving the quality of Earth System Services in the country. This timely investment has led to the substantial improvement in weather and climate forecasts and warnings, Ocean state forecasts and warnings, Tsunami warnings, better monitoring of earthquakes. In this vyakhyaan the progress made during last 8-10 years in Earth System Science Services will be discussed. Particularly the points to be discussed will be; a) details of atmospheric and oceanic observational network and mathematical modeling strategy, b) the improvement in monsoon forecasts, warnings of Tropical cyclones, heavy rainfall, flash floods and heat waves, ocean state, storm surges, Tsunamis, c) development of technologies for drinking water for islands, restoration of beaches from coastal erosion, d) Air and Sea Water quality monitoring and prediction, e) development of technologies for deep sea exploration and mining, f) exploration of marine biodiversity and marine living resources, g) Ocean Survey and Exploration h) Seismological network and research on Earthquakes, i) exploration of three poles (Arctic, Antarctic and Himalayas). Finally, the future prospects and details of scientific programs planned for next five years will be also discussed.

THE MYSTERY OF VENUS LIGHTNING

Date
2021-10-13
Speaker
Dr. Ralph Lorenz
Venue
ONLINE

Abstract

Earth's twin planet shines brightly in our skies because of its extensive clouds. But do these clouds, or processes beneath them, produce lightning? This question has yielded positive and negative answers for over forty years. It seems clear that whistler-mode waves can be observed at Venus, as ample detections by Pioneer Venus (electrical fields) and Venus Express (magnetometer) attest. But there may be non-lightning processes that yield such waves. An important observation is that of Cassini, which detected no lightning radio emissions during two Venus flybys, yet many during an Earth flyby. Such 'control' experiments to understand the false positive rate and detection efficiency of any observation are essential to establishing credible discovery of a phenomenon like lightning. Optical flash surveys have similar negative and positive results. Negative results could be attributed to flashes occurring below the main cloud deck, but the charge generation mechanisms there are not obvious. Positive results may be due to real flashes, or reflections from debris particles shed by spacecraft, or radiation effects. A tentative flash detection by Akatsuki at least appears to rule out a radiation effect by the time signature of the flash. Again, careful control of experiments is essential. Perhaps the only way to finally resolve the question is a combined optical and radio/magnetic observation able to spatially locate a source of both, from an orbiting platform where the time-area product can be large enough to establish statistically-meaningful results.

A Song for the SOL

Date
2021-10-06
Speaker
Dr. Madhulika Guhathakurta
Venue
ONLINE

Abstract

The World Space Week (WSW) is an international event celebrated every year from the 4th to 10th of October as declared by the United Nations General Assembly in 1999. This event commemorates the contributions of space science and technology to the betterment of the human condition with a central theme each year. In 2021, World Space Week is dedicated to the theme of “Women in Space”. Befitting to the theme to inspire the next generation and celebrating the accomplishments and contributions of women to the space sector, the 10th PRL ka Amrut Vyakhyaan is organized to mark the celebration of world space week. The vyakhyaan will be delivered by Dr. Madhulika Guhathakurta who is a heliophysicist and has worked as an educator, scientist, mission designer, directed and managed science programs at NASA, and has built instruments for spacecraft. She has been a long standing eclipse enthusiast and has led missions to study 11 total solar eclipses across the world. She is currently pushing new boundaries by using Artificial Intelligence/Machine learning for furthering our understanding of science and exploration. This talk will be a short journey through her career.

Dynamics of aurora and airglow in the upper atmosphere and space around the Earth

Date
2021-09-29
Speaker
Prof. Kazuo Shiokawa
Venue
ONLINE

Abstract

Aurora and airglow are light emissions from the upper atmosphere at altitudes of 80-600 km where International Space Station and most low-altitude satellites are flying. Aurora is excited by collision of space plasma with the Earth’s atmosphere, while airglow is excited mainly by solar ultraviolet emissions. The space plasmas originally come from the sun and from the Earth’s atmosphere. They are stored and energized in the space around the Earth. We can visualize dynamics of space plasma and upper atmosphere through aurora and airglow. The dynamic variations contain geomagnetic storms and substorms, plasma bubbles, and travelling ionospheric disturbances. These space plasma and upper atmospheric dynamics often cause satellite anomaly, satellite positioning error, radiation dose of satellites and astronauts, ozone destruction, and so on, as referred to the space weather effect.

Prospects in Solar Physics for the Next Decade: a Multi-messenger Era

Date
2021-09-22
Speaker
Dr. Valentin Martinez Pillet
Venue
ONLINE

Abstract

The start of operations of the NSF’s Daniel K Inouye Solar Telescope (DKIST) in late 2021 coincides with the science phases of two solar encounter missions, Parker Solar Probe (NASA) and Solar Orbiter (ESA/NASA). The three facilities constitute a multi-messenger suite destined to help us understand how the heliosphere is magnetically connected to the Sun. By getting closer to the Sun, the two spacecrafts can measure in-situ the pristine consequences of the processes observed at the solar surface with unprecedented detail and sensitivity using DKIST. The ability to observe spectropolarimetric signals from the solar corona is a novel and unique capability that DKIST will contribute to this collaboration. This talk will outline some multi-messenger science cases that will benefit from combining the three facilities using different vantage configurations created by their orbits around the Sun. This discussion will be useful to update on the status of DKIST, but also of the NSO operated synoptic network GONG (with a node in Udaipur) and the plans for a future improved network that replaces it.

GREEN ENERGY AND CLEAN WATER FROM THE OCEANS

Date
2021-09-15
Speaker
Dr. Purnima Jalihal
Venue
ONLINE

Abstract

In today’s world the need for electricity and water needs no emphasis. Rapid industrialization, population growth coupled with human failures in managing the scenario have led to severe power and water stress. Fossil fuels are known to be depleting and new sources of power are being explored. Another important factor to look for in new sustainable energy sources is linked with the impending disaster of climate change and global warming. While solar, wind, biomass and other forms are already being tapped across the globe, energies which can be harnessed from the vast ocean have yet to move from the research arena. The oceans offer huge opportunities to try new technologies without affecting human settlements or the environment. The current efforts are therefore directed in developing technologies for harnessing marine renewable energies. In particular, ocean energy can be harnessed in the form of waves, currents, tides and temperature gradient. The other prime need today is for water. While purification, storage, distribution of the water are all part of the scenario, in order to increase water availability, desalination in coastal areas is a possible solution. Various methods of desalination are being used although some may not be environmentally friendly when brine formation results or disposal of used components like membranes becomes necessary. Further, the difference in temperature between the sea surface and at a greater depth can be utilized to harness energy. This is called Ocean Thermal Energy Conversion or OTEC. Thermal desalination is a spin-off from the OTEC cycle. Today NIOT has developed expertise in the design, assembly and running of low temperature thermal desalination (LTTD) plant in islands, coastal power plants and offshore in deep waters. The thermal desalination technology developed by NIOT has improved the health of the islanders and six more plants are now being installed. Scaling up of this technology in coastal power plants is being taken up with a project underway for the Tuticorin Thermal Power Station. Another flagship project is an OTEC powered LTTD plant being set up in Kavaratti, Lakshadweep which will be self- powered and will not require to use diesel generators. The need of the hour is to develop and scale up viable environmentally friendly renewable ocean energy forms and power thermal desalination systems with clean and green renewable energy.

Safety of nanomaterials: A journey from research to policy

Date
2021-09-08
Speaker
Prof. Alok Dhawan
Venue
ONLINE (YouTube)

Abstract

Nanotoxicology is a study of the toxicity of nanomaterials. Nanomaterials, even when made of inert elements, at times become highly active at the nanometer dimension due to their altered physical and chemical properties. The toxicology studies are intended to determine whether and to what extent these properties may pose a threat to the environment and to human beings. The same novel properties making nanoparticles attractive could make them potentially toxic too. Exposure to nanomaterials can be due to contact via skin, inhalation and oral ingestion. However, it could also happen indirectly through the environment or food chain. The former can be controlled and mitigated, while assessment of the latter is very difficult both to ascertain as well as to mitigate. While assessing the toxicity of engineered nanomaterials (ENMs), several things need to be accounted for, such as, size, shape, surface area, coatings, stability, dispersion, uptake, excretion of ENMs. Depending on the materials and its intended use, the appropriate model needs to be identified to assess the toxicity of the ENMs. Initial toxicity of ENMs is done in vitro and subsequently in vivo using various animal and alternate animal models. This allows for hazard identification as well as an appropriate risk assessment. Hazard identification of ENMs can be done in vitro and in vivo, using various models by assessing cytotoxicity, genotoxicity, immunotoxicity, neurotoxicity, hepatic toxicity, renal toxicity, cardiotoxicity etc. For assessing the environmental impact of ENMs, several models at different trophic levels have been used such as E. coli, Drosophila, Zebrafish, Daphnia, plants. Globally, an effort is being made to develop ENMs through “safe by design approach” and employ the precautionary principal for their usage. In India, guidelines have now been published both for the safety assessment of nanopharmaceuticals as well as for the nano-based agri-input and food products.

Floods in a Changing Climate

Date
2021-09-01
Speaker
Prof. P P Mujumdar
Venue
ONLINE (YouTube)

Abstract

With an increased climate variability under climate change, the risk of hydrologic extremes of floods is known to be increasing globally. The recently released IPCC report provides clear pointers to enhanced risk of floods in South Asia. While, with the current scientific knowledge, it is not possible to attribute a given extreme event to climate change, recurring patterns and increased frequencies of floods are clearly visible both at larger global scales and at smaller regional scales. The recent (Feb 2021) floods in the Himayalan river basin of Alaknanda induced purportedly by avalanche fall, the Kerala floods of 2018, Chennai floods of 2015 and the Uttarakhand floods of 2013 are the recent Indian examples of devastating floods that claimed hundreds of lives and resulted in huge economic losses. Such recurring floods point to the need of a better scientific understanding of the events. The magnitudes of precipitation induced floods depend on precipitation intensity, volume, timing, antecedent conditions of rivers and hydrologic response the drainage basins. Projecting the flood magnitude and frequency under climate change must therefore consider these critical aspects. Projections with currently available methodologies are however burdened with a high uncertainty, as the climate models typically do not capture the events at the time and space scales at which floods occur. In this talk, a brief overview of the recent work related to hydro-meteorologic aspects of floods in a changing climate is provided. Specifically, the following key issues are addressed : increase in extreme precipitation at a range of spatio-temporal scales and the associated non-stationarity in the process, hydrologic modelling of floods in the face of limited ground observations, detecting human signatures in the extremes and quantifying uncertainties in projections of the extremes.

Our immunity and emerging diseases

Date
2021-08-25
Speaker
Prof. Chandrima Shaha
Venue
ONLINE

Abstract

Bacterial, viral and fungal infections continue to be major challenges across the world. Our immune system protects us against the invading pathogens and failure of the immune response cause diseases. During the course of evolution, the constant tussle between the human hosts and the pathogens shaped the immune system that we have today. The understanding of immunity forms the basis of designing of vaccines and drugs and lessons from pandemics of the past emphasises the crucial role that vaccines play in our fight against diseases. Evolutionary events unfurling in recent times shows how the SARS-CoV-2 changes to become a better pathogen capable of infecting with greater efficiency. The clues to a successful defense against COVID-19 lies in the generation of knowledge on the biology of the SARS-Cov-2 and understanding the nature of the COVID-19, as is evident from the remarkable progress made by science and technology that helped us to mitigate our plight during the current pandemic.

Confined water: Many surprises: PRL Ka Amrut Vyakhyaan 03

Date
2021-08-18
Speaker
Prof. Prabal K Maiti
Venue
ONLINE

Abstract

Water enters the hydrophobic cavity of narrow CNTs despite enthalpy penalty due to loss of hydrogen bonds and forms ‘solid-like’ ordering at room temperature. We give the thermodynamics of water entry inside hydrophobic nanotube by calculating the free energy of water. We also show that the water molecules inside the CNT cavity get aligned by flow to have a net dipole moment along the flow direction. With increasing flow velocity, the net dipole moment first increases and eventually saturates to a constant value. This behavior is similar to the Langevin theory of paraelectric with the flow velocity acting as an effective aligning field. This observation provides a way to control the dipolar alignment of water molecules inside nanochannels with possible applications in nano-electrical devices. If time permits, we will discuss two other interesting problems in confined water namely: (i) the mechanism of water permeation in helium impermeable grapheme oxide (GO) membrane based on potential of mean force (PMF) calculation and (ii) proton kinetic energy anomalies in the confined water and compare our calculated mean proton kinetic energy to those obtained by deep inelastic neutron scattering (DINS) experiments.

REACHING THE SKY: INDIAN LAUNCH VEHICLES

Date
2021-08-11
Speaker
Shri S. Somanath
Venue
ONLINE

Abstract

The story of rockets in India started in a fishing village of Thumba near Thiruvananthapuram, where Thumba Equatorial Rocket Launching Station (TERLS) for launching sounding rocket was established. The first launch was on November 21, 1963, which carried a 20 kg payload to a height of 200 km using an American made Nike-Apache rocket. Indian space program so far developed five launch vehicles and has presently three operational vehicles with payload capability up to 4000kg. The story of the development of SLV-3 is a fascinating one, which is linked to the inspiring story of Dr. APJ Abdul Kalam. The multidisciplinary nature of the technology, technology denials, its strategic nature and dual use possibility made rocket technology a complex affair and to be mastered with hits and misses. The development of SLV-3 and ASLV were the learning grounds and the PSLV onwards became operational vehicles, as envisaged by Dr. Satish Dhawan in his famous Dhawan diagram. SLV-3 was successfully flown in 1980 and placed a 35 kg Rohini spacecraft in a low earth orbit. The development of ASLV was aimed at demonstration of the technologies needed for the launch vehicles in the operational phase. The PSLV programme which commenced during the ASLV period became the workhorse of ISRO and has recorded a series of successful missions with many evolutions to its credit. The development of GSLV enabled India to place operational communication satellites in GTO. Development of cryogenic technology was a landmark achievement which culminated in the realization of fully indigenous C25 stage for GSLV Mk-III. Today India is one among the few nations which has the capability to design and realize any class of satellites and launch from its own soil. The remarkable missions of Chandrayaan and Mangalyaan were achieved with PSLV and GSLV Mk-III. This vyakhyaan will cover the evolution of launch vehicles, the key technologies mastered, present strengths in this domain, current developments and future programs keeping in view of the technological and industrial strength this nation has at present.

OSIRIS-REx: Sample science and the geologic context for the return regolith from active asteroid Bennu

Date
2021-08-04
Speaker
Prof. Harold C. Connolly Jr
Venue
ONLINE

Abstract

The OSIRIS-REx space mission is part of NASA's New Frontiers program and has a main goal of returning at least 60 g of pristine regolith from asteroid Bennu. On May 10th of this year, the spacecraft successfully performed a departure maneuver and left the vicinity of the Target asteroid, having achieved all of its science and engineering goals flawlessly, including the collection of regolith from asteroid Bennu. This talk will review the mission, the major findings of the mission as they pertain to sample science, discussion how our finding may illuminate the origins and evolution of the collected regolith. It will review the OSIRIS-REx collection and stowing (or the sample) process, what we know about the collected sample, and review some basic aspects of how the team will analyze and curate the sample when it returns.