LECTURES AND SEMINARS

Topic: Mysteries of light: from Newton to Einstein
Speaker: Prof. Satish Chand Abbi

Professor Abbi obtained his Ph D degree from Cornell University (USA) in 1971 and after five years of teaching/research assignments in the US, he returned to India to join the Indian Institute of Technology, Delhi in 1976. He, along with Professor S.Chopra established the ‘Quantum Electronics Laboratory’ in 1978. A Photon Correlator was developed in this laboratory for the first time in India and work in the area of ‘Photon Correlation Spectroscopy’ was initiated. Five years later, he along with Professor K.P. Jain, established the ‘Laser Technology Research Programme’, which now houses one of the best Laser Spectroscopy Laboratories in India. The group set-up various international collaborative research programmes in Laser Spectroscopy with many groups in France, United Kingdom, Japan, and Israel.

Professor Abbi has guided 12 Ph D students and 30 MS/M Tech projects. He has published more than 70 papers in Journals of international repute. His major contributions are in areas that include: Non-linear Optics, Laser Raman and Photoluminescence Spectroscopy of Semiconductors, Laser generation of Nano-Semiconductors and their Characterization by Laser spectroscopy. This work resulted in many papers in prestigious international journals that include: Physical Review Letters (3), Physical Reviews B (10), Journal of Applied Physics (10), Applied Physics Letters and many national journals. Professor Abbi, along with Dr S A Ahmad, published a book titled ‘Non-linear Optics and Laser Spectroscopy’. Professor Abbi has held various administrative positions including: Head, Department of Physics at IIT Delhi, Coordinator of the Laser technology Research Programme, President of the India Laser Association, Director of the Science and Engineering Research Council (DST) School on Non-linear Optics and Laser spectroscopy and President of the Board of Recreational and Creative activities of Indian Institute of Technology Delhi.


Date: May 14, 2013 (Tuesday)
Time: 4:30-5:30 p.m.
Venue: Lecture Hall No. 208, IIT Mandi

Abstract

What is light? How does it travel from one point to another?

How does light travel from one point to another? Mach’s Principle was the motivating idea for Einstein to develop the General Theory of Relativity. The General Theory predicts that light travelling in the Celestial space would bend while passing close to the Sun. On a terrestrial scale, light bends when passing from one medium to the other or travelling through inhomogeneous media. Is there a common principle followed in both cases? In order to explore this possibility, we develop a general discussion by asking the question that in going from one point to another, weather (a) light travels in a straight line, or (b) it chooses the shortest path, or (c) it chooses a path to reach the target point in the minimum time (Fermat's Principle).Through a description of some surprisingly simple experiments we conclude that light always chooses the shortest path as it does in outer celestial space as enunciated by Einstein. In this description, the length scales change but the time intervals remain the same as light passes from one medium to another. This is a refreshingly new way of looking at the refraction of light.

“What is light?” Is it a stream of particles called `Corpuscles' as proposed by Newton or is it a wave as described by Huygens? Once again, we depend on a very simple experiment done by almost every science high school student to conclude that light certainly does not consist of the ‘Corpuscles’ described by Newton. We consider next the Einstein’s concept that light can be considered as a stream of particles called ‘Photons’ and show that this picture is also in agreement with the experimental results of the same simple experiment. We thereby confirm the dual nature of light. The discussion leads us to a refreshingly new visualization of Nature as consisting of finite mass Newtonian particles as well as the Zero mass Boson called ‘Photon’. In this way we ascribe the discovery of the Zero of the mass scale to Satyendra Nath Bose.

We mention some more mysteries of light and conclude by discussing that incorporation of concepts and principles have the potential of generating more interest and discussion among the students than by simply enunciating the Laws of Physics and facilitating their use in problem solving.

Topic: A CRITIQUE OF THE BIG BANG COSMOLOGY
Speaker: Prof. Jayant Vishnu Narlikar

Jayant Narlikar was born on July 19, 1938 in Kolhapur, Maharashtra and received his early education in the campus of Banaras Hindu University (BHU), where his father Vishnu Vasudeva Narlikar was Professor and Head of the Mathematics Department. His mother Sumati Narlikar was a Sanskrit scholar. After a brilliant career in school and college, Narlikar got his B.Sc. degree in 1957. He went to Cambridge for higher studies, becoming a Wrangler and Tyson Medallist in the Mathematical Tripos. He got his Cambridge degrees in mathematics: B.A.(1960), Ph.D. (1963), M.A. (1964) and Sc.D. (1976), but specialized in astronomy and astrophysics. He distinguished himself at Cambridge with the Smith’s Prize in 1962 and the Adams Prize in 1967. He later stayed on at Cambridge till 1972, as Fellow of King’s College (1963-72) and Founder Staff Member of the Institute of Theoretical Astronomy (1966-72). During this period he laid the foundations of his research work in cosmology and astrophysics in collaboration with his mentor Fred Hoyle.

Narlikar returned to India to join the Tata Institute of Fundamental Research (1972-1989) where under his charge the Theoretical Astrophysics Group acquired international standing. In 1988 he was invited by the University Grants Commission as Founder Director to set up the proposed Inter-University Centre for Astronomy and Astrophysics (IUCAA). Under his direction IUCAA has acquired a world-wide reputation as a centre for excellence in teaching and research in astronomy and astrophysics. He retired from this position in 2003. He is now Emeritus Professor at IUCAA.

In 1966, Narlikar married Mangala Rajwade, a Ph.D. in mathematics. They have three daughters, Geeta, Girija and Leelavati, all of whom have opted for careers in science.

Narlikar is internationally known for his work in cosmology, in championing models alternative to the popularly believed big bang model. He was President of the Cosmology Commission of the International Astronomical Union from 1994 to 1997. His work has been on the frontiers of gravity and Mach’s Principle, quantum cosmology and action at a distance physics. He has received several national and international awards and honorary doctorates. He is a Bhatnagar awardee, as well as recipient of the M.P. Birla award, the Prix Janssen of the French Astronomical Society and an Associate of the Royal Astronomical Society of London. He is Fellow of the three national science academies as well as of the Third World Academy of Sciences. Apart from his scientific research, Narlikar has been well known as a science communicator through his books, articles, and radio/TV programmes. For these efforts, he was honoured by the UNESCO in 1996 with the Kalinga Award.

Narlikar recently broke new grounds in space research. Since 1999 he has been heading an international team in pioneering experiments designed to sample air for microorganisms in the atmosphere at heights of up to 41 km. Biological studies of the samples collected in 2001 and 2005 led to the findings of live cells and bacteria, thus opening out the intriguing possibility that the Earth is being bombarded by microorganisms some of which might have seeded life itself here.

Narlikar was decorated Padmabhushan in 1965, at the young age of 26. In 2004 he was awarded Padmavibhushan. In 2011, the Government of the State of Maharashtra gave him the State’s highest civilian honour of Maharashtra Bhushan.


Date: April 01, 2013 (Monday)
Time: 4:30-5:30 p.m.
Venue: Lecture Hall No. 208, IIT Mandi

Abstract

This talk will begin by a historical introduction to the topic of cosmology describing how as a scientific discipline it has sought to emphasize facts. The present big bang cosmology, often described as the ‘standard model’ also started that way. However, of late several speculative elements have entered the subject. These, like inflation, non-baryonic matter and dark energy will be briefly described. It will be argued that the last word in the subject has not yet been said and there should be room for alternative ideas.

Topic: The Internet without IP addresses - A new approach to the Internet Architecture
Speaker: Dr. Saleem Bhatti

Saleem Bhatti is a Professor at the School of Computer Science at the University of St Andrews.
He was previously the Director of the "e-Science National Centre of Excellence on Networked Systems" at University College London (UCL), and is now the Theme Leader for the Scottish Informatics and Computer Science Alliance (SICSA) "Next Generation Internet" Theme.

His past work covers network and systems monitoring and management; network architecture; mobile systems; network security; QoS (Quality of Service); adaptive systems; and high-speed networking. He is also involved with industry in various consultancy roles in the area of networking technology and systems, including past work for OFCOM, the UK communications regulator.

Current projects include a work-in-progress for a next-generation evolution of the Internet Protocol; and the India-UK Advanced Technology Centre (IU-ATC) in Next Generation Networks, in which investigations include QoS and energy-aware systems for future networks.

Prof Bhatti holds a B.Eng (Hons), MSc, and a PhD all from University College London (UCL), UK.

More information on ILNP can be found here.


Date: 07 March, 2013 (Thursday)
Time: 4-5 P.M.
Venue: Room 1, Stable Complex, Kamand

Abstract

There has been concern over many years about the growth of the Internet and the ability of the Internet Protocol to provide new functionality that was not part of its original design. For example, concerns over scalability have been related to routing table growth in the default free zone (DFZ). Additionally, users would like to have harmonised functionality, such as mobile hosts and networks, packet-level security, and multi-homing. Many of the solutions for dealing with scalability and new functionality have been designed and implemented in isolation, as engineering retro-fits to the core IP functionality, and so do not operate well when used together. We take a fresh approach to the architecture of the Internet, looking at the general concept of naming to provide scalability and harmonised functionality. This talk will introduce the Identifier Locator Network Protocol (ILNP) as a way of realising this new architectural approach. The architectural change with respect to the current Internet will be explained, as well as an outline of how the new architecture can be engineered for today's networks.

Seminars Archive

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