PREVIOUS COLLOQUIA - 2010

Date

Speaker

Title

Abstract

08.01.2010

Prof.  Sankar Pal,

ISI, Kolkata

Machine Intelligence, Rough-Fuzzy Granules and Minig: Concepts, Features and Applications

Different components of machine intelligence are explained. The role of rough sets in uncertainty handling and granular computing is described. The significance of its integration with other soft computing tools and the relevance of rough-fuzzy computing, as a stronger paradigm for uncertainty handling, are explained with examples. The tasks of rough-fuzzy case generation, clustering, and knowledge encoding in ANN are then addressed, along with the role of granules.

Superiority of the methods in terms of computation time, performance, network size, and uncertainty handling is demonstrated; thereby making them suitable for mining large data sets. Features and merits of case generation algorithms are described on problems of multispectral image segmentation, while those of rough-fuzzy clustering are demonstrated for determining bio-bases (c-medoids) in encoding protein sequence for analysis.

The talk concludes with stating the possible future uses of the methodologies, concept of generalized rough entropy, relation with computational theory of perception (CTP), and the challenges in mining

12.02.2010

Prof. Sugata Marjit,

Director, Centre for Social Sciences

Game theoretic approach to the problem of displaced persons

05.03.2010

Prof. Biswarup Mukhopadhyaya,

HRI, Allahabad

The Large Hadron Collider and New Physics: Some Reflections on the Invisible and the Visible

23.04.2010

Prof. Raj Nath Bhat,

BHU, Varanasi

Swanimvijnan: Hind Arya Bhasha Samoh ke Sandarbh Mein

14.05.10

Prof. Mukunda P Das,

The Australian National University, Canberra, Australia

Super-Phenomena in Quantum Physics

Super-phenomena in quantum physics are comprised of superconductivity and superfluidity. Both are electrical and mechanical manifestation of the same phenomena in a correlated environment. The subject has a long history that dominated the last century and curretly it is one of the hottest topics of research in condensed matter science. There are many surprises, some are understood and many are yet to be understood. In this talk, which will be pedagogic in nature, I shall try to cover many important aspects of both superconductivity and superfluidity

21.05.2010

Mr. Sumit Kr. Sen

Author & Naturalist

Birdwatching – Citizens and Science

Birds are an essential fabric of life on earth and birdwatching is a wonderful active outdoor hobby. But birdwatching goes beyond the simple observation of birds. Today, birders play a big part in the better understanding of birds and the key role they play as biological indicators. The work of such amateurs contributes to collaborative research in ornithology and conservation science leading to awareness that would be impossible without widespread voluntary participation. In many ways birdwatching is a good example of a rewarding hobby which can contribute meaningfully to the wellbeing of mankind.

16.08.2010

Dr. Girish S Agarwal,

Nobel Foundation Chair and Regents Professor, Oklahoma State University, USA

Electromagnetically Induced Transparency and Quantum Optics in Nano Mechanical Systems

The current research in nano mechanical systems is driven by the possibility of realizing the quantized motion of macroscopic systems.  Efforts are on to cool such systems to their ground state so that quantum optical effects can be realized. In the meanwhile the nonlinear optical studies of such systems is yielding remarkable results. We have rather surprisingly found a new “avatar” of EIT in such systems opening up the possibility of applying all that one has learnt about EIT in last two decades. We discuss the spontaneous generation of Stokes and anti-Stokes fields and the possibility of beating the standard motional quantum limit of a nano mechanical system.

24.08.2010

Prof. N Mukunda,

IISc, Bangalore

The Relation Between Mathematics and Physics

Prof. Deepak Dhar,

TIFR, Mumbai

Equation of state of a model glass

Traditionally, glasses are treated as non-equilibrium states of matter, very slowly relaxing to equilibrium. However, on the time-scale of milliseconds to years, the window glass appears to be in some kind of thermal equilibrium, and it should be possible to calculate its properties theoretically, from the basic principles of statistical mechanics.

However, the standard method of determining properties like equation of state of matter in equilibrium stat-mech using the canonical partition functions only gives the properties of crystalline quartz, and not of glass. One needs to modify the prescription, and make only a restricted sum over states. While the idea of restricted ensembles is not new, it has not been possible so far to actually calculate such restricted partition functions in any non-trivial case exactly. I will describe a simple model of interacting particles, which shows a glassy phase, and where the equation of state can be determined exactly.

Richard Packard

University of California, Berkeley

Superfluid weak links; physics and applications

Superfluid helium is an “entangled” Bose condensed state of matter in which the individual atoms relinquish their identity to share in a macroscopic wavefunction whose quantum phase depends on external fields. The key element required to measure the quantum phase information is an array of nanometer sized apertures that exhibit properties described by Josephson’s equations. We have studied these so-called superfluid weak links in both superfluid 3He and 4He. A remarkable observation is that when we try to push the superfluid through the apertures the fluid oscillates at a quantum frequency rather than flowing down the pressure gradient. By exploiting the weak link properties we have developed Superfluid Helium Quantum Interference Devices (SHeQUIDs) which are analogs of superconducting SQUIDs. These novel devices reveal the absolute rotation state of the walls confining the liquid and may find uses in geodesy and inertial navigation. Other SHeQUIDs may detect Aharonov-Bohm phase shifts in neutral nonpolar matter and may set upper limits to gravito-magnetic fields present near rotating masses.

            This talk will be understandable at the undergraduate level. For related papers and further discussion visit: http://www.physics.berkeley.edu/research/packard/