Colloquium

Date : 20-01-2021
Time : 16:00:00
Speaker : Dr. Mrutyunjay Mohapatra
Area : DEAN'S OFFICE
Venue : ONLINE

Abstract

Most of these natural disasters (about 80%) are hydro-meteorological in nature. They include cyclones, floods, droughts, landslides, heat wave, cold wave, thunderstorms, and tornadoes. The risk management of these natural disasters includes several steps based on its severity and impact: (i) hazard analysis, (ii) vulnerability analysis, (iii) preparedness and planning, (iv) early warning, (v) prevention and mitigation. The early warning component includes: (i) skill in monitoring and prediction of natural hazards, (ii) effective generation and dissemination of products for warning, (iii) coordination with emergency response units, and (iv) public awareness and perception about the credibility of the official predictions and warnings. Though there have been significant improvement in multi-hazard monitoring and warning system in recent years due to various initiatives of Ministry of Earth Sciences (MoES) / India Meteorological Department (IMD) and policy frame work of Government of India, there is still scope for improving (i) mesoscale hazard detection and monitoring, (ii) spatial and temporal scale of forecasts through technological upgradation, (iii) impact based forecast and sectoral applications, (iv) warning communication to last mile. All these aspects will be discussed with respect to current status, existing gap areas, and future scope.

Date : 13-01-2021
Time : 10:30:00
Speaker : Prof. Mohit Randeria
Area : DEAN'S OFFICE
Venue : ONLINE

Abstract

Understanding limits on the superconducting transition temperature Tc is a question of fundamental and practical importance. The talk will begin with an overview of experiments and earlier ideas on limits on Tc, followed by a description of how recent developments in ultra-cold Fermigases and in quantum materials challenge conventional ideas on what determines Tc. Recent progress [1] on rigorous bounds on the super fluid phase stiffness will then be discussed. These lead to upperbounds on Tc of 2D systems, irrespective of pairing mechanism or strength. Applications to the 2D BCS-BEC cross over in cold atoms, where Tc is shown to be bounded by one-eighth the Fermi temperature and to a variety of quantum materials including magic-angle twisted bilayer graphene will be discussed. Finally, the open question of deriving rigorous upper bounds on Tc in 3D will be discussed. [1] T. Hazra, N. Verma, M. Randeria, Physical Review X 9, 031049 (2019)

Date : 06-01-2021
Time : 16:00:00
Speaker : Prof. Ravi Shankar Nanjundiah
Area : DEAN'S OFFICE
Venue : ONLINE

Abstract

The Indian Summer Monsoon governs the pulse of this country. It is known to vary at various scales. In this talk, we will discuss the mean monsoon and its variability at various scales ranging from within the season at extremely short scales (<10 days) commonly known as the synoptic scale, the intraseasonal variability (10-60 days), and from season-to-season (commonly known as interannual variability). In addition, we will briefly discuss some global phenomena that modulate the strength of monsoon, such as the El-Nino. We will also examine if this El-Nino and Monsoon linkage fluctuates with time. Additionally, we will also examine if the strength of intraseasonal variability also fluctuates and whether anthropogenic factors also affect it. Finally, we will also examine if the monsoon has fluctuations from decade-to-decade and factors that could cause this decadal variability.