Sumanta Chakraborty (IACS, Kolkata, India) and Sudipta Sarkar (IIT Gandhinagar, India)
24 March 2025 to 04 April 2025
Ramanujan Lecture Hall, ICTS Bengaluru

We are living in an exciting era of great discoveries in the field of gravitational physics. The detection of gravitational waves by the LIGO-VIRGO-KAGRA (LVK) collaboration starting from  2016 has already led to an enormous interest in various aspects of the physics of compact objects. The recent observations of the shadows of the galactic centers for M87 and Milky Way, by the Event Horizon Telescope (EHT), have further resulted into diverse research programs on the nature of compact objects. The primary emphasis of these observations is to test the theory of general relativity at the strong-field regime and to understand the nature of the astrophysical compact objects. Several recent developments led to the extensive use of various new mathematical and computational techniques to probe the physics associated with these compact objects. 

The primary motivation of the school would be to learn from leading researchers about several crucial aspects of the physics of compact objects. The program is designed to discuss the possible answers to following important questions:

  • What are the observational signatures of the existence of an event horizon?
  • Is it possible to observationally distinguish between horizonless ultra-compact objects and black holes?
  • How to understand the physics of horizonless ultra compact objects, particularly the formation, and the stability?

In this school, the emphasis would be on the physics of black hole mimickers and ultra-compact objects in the context of both EHT and LVK observations. The first week will be devoted to the observation of the shadow of compact objects by the EHT collaboration and its consequences. In the second week, we will study how gravitational wave observations can be used to test the nature of central compact objects and possible environmental effects on black holes. We will also have an understanding of the physics of ultra-compact objects, focussing on their formation and stability. 


1. EHT observations and black hole shadow by Prof. Dimitrios Psaltis, Georgia Tech, USA

2. Physics of ultra compact objects by Prof. Carlos A. R. Herdeiro, University of Aveiro, Portugal

3. Probing black hole mimickers using gravitational wave observations by Prof. Paolo Pani, Sapienza University of Rome, Italy

4. Environmental effects on black holes and exotic compact objects by Prof. Vitor Cardoso, Niels Bohr Institute, Denmark

Registration will start from 1st September 2024.

​Eligibility criteria: PhD Students and Postdoctoral fellows working in related areas. Preference will be given to senior PhD students and junior post docs. The topics to be covered in this school require prior knowledge about basics of general relativity and black hole physics.

ICTS is committed to building an environment that is inclusive, non-discriminatory and welcoming of diverse individuals. We especially encourage the participation of women and other under-represented groups.

30 October 2024
beyondhorizon  ictsresin