Tag: astrophysics

Conversation with Debarati Chatterjee

Debarati Chatterjee is a Professor of theoretical astrophysicist at IUCAA and the Chair of Education and Public Outreach for the LIGO-India project. An avid science communicator, she founded the Indian branch of the Pint of Science festival and regularly holds outreach events in multiple languages to make science accessible to all.

In this episode, we explore her intellectual journey so far.

References:

1.‘‪Debarati Chatterjee‬ – ‪Google Scholar‬’. Accessed 18 February 2026. https://scholar.google.com/citations?user=wL7lJoUAAAAJ&hl=en.

2.‘Debarati Chatterjee – IUCAA’. Accessed 18 February 2026. https://www.iucaa.in/en/faculty-research/debarati.

3.‘Facebook’. Accessed 18 February 2026. https://www.facebook.com/AstroRoamer.

4.India. ‘Pint of Science India’. Accessed 18 February 2026. https://www.pintofscience.in.

5.India. ‘The Team’. Accessed 18 February 2026. https://www.pintofscience.in/team.

6.‘iPortfolio Bootstrap Template – Index’. Accessed 18 February 2026. https://web.iucaa.in/~debarati/.

7.‘LIGO India (@ligoindia) • Instagram Photos and Videos’. Accessed 18 February 2026. https://www.instagram.com/ligoindia/.

8.Linktree. ‘Ligoindia | Twitter, Instagram, Facebook’. Accessed 18 February 2026. https://linktr.ee/ligoindia.

9.‘Pint of Science India (@pintofsciencein) • Instagram Photos and Videos’. Accessed 18 February 2026. https://www.instagram.com/pintofsciencein/.

10.‘Prof. Debarati Chatterjee | LinkedIn’. Accessed 18 February 2026. https://www.linkedin.com/in/prof-debarati-chatterjee-a6072a/.

11.‘Prof. Debi (@debi.Physix) • Instagram Photos and Videos’. Accessed 18 February 2026. https://www.instagram.com/debi.physix/.

12.Sharma, Kanika. ‘I Encourage Women to Claim Their Space in Astrophysics and Beyond’. Nature, ahead of print, 21 November 2025. https://doi.org/10.1038/d41586-025-03400-1.

13.X (Formerly Twitter). ‘Prof. Debarati Chatterjee (@astro_roamer) / X’. 9 February 2019. https://x.com/astro_roamer.

When Chandra wrote to Hawking

Learning is a lifelong process, and even the best researchers have to update their knowledge as and when they come across new information. Subrahmanyan Chandrasekhar was undoubtedly one of the most accomplished mathematical astrophysicists in the 20th century, and his range of topics covered almost all aspects of astrophysics.  Chandra (as he was known) was a lifelong learner, and took up new topics within astrophysics, researched them deeply, and wrote definitive books on them, which are still of great utility even today. In his research process, Chandra consulted various scholars across the world, irrespective of their age, and learned new things.

In 1967, Chandra, aged 57, wrote a letter to a 25-year-old researcher, Stephan Hawking, to learn more about his work ‘on the occurrence of singularities in cosmology’. In this letter, which is written in a desperate tone, Chandra mentions that he is grappling with some mathematical aspects of Stephen Hawking’s work and is asking him for references that he can consult to understand his papers. Chandra describes reading Hawking’s papers as  ‘climbing a staircase moving downwards’. Below, I reproduce the letter (from the University of Chicago archives).

 To this letter, Hawking dutifully replies (see below), suggesting specific books on topology and differential geometry. Hawking also suggests some of his published papers. Hawking himself downplays his knowledge of mathematical aspects related to the work, and mentions that it improved after he consulted the mentioned books. Below, I reproduce the handwritten letter (from the University of Chicago archives).

There are two aspects that are interesting to note:  one is the fact that even accomplished researchers have to learn and relearn many things as they get exposed to new information, which calls for humility and setting aside egos, and the second aspect is that ideas are built on existing ideas available at that time, and a major part of it is to learn from papers, books and of course communicating with people, as Chandra did in this case.

Science, after all, is a human endeavor.

Gerhard Herzberg – scientific life


References:

Pavan Kumar, G. V. “Gerhard Herzberg (1904–1999): A Pioneer in Molecular Spectroscopy.” Resonance 29 (2024): 1339. https://www.ias.ac.in/describe/article/reso/029/10/1339-1345.

Stoicheff, Boris. Gerhard Herzberg: An Illustrious Life in Science. Ottawa : Montréal ; Ithaca N.Y.: Canadian Forest Service,Canada, 2002.

Stoicheff, Boris P. “Gerhard Herzberg PC CC. 25 December 1904 – 3 March 1999.” Biographical Memoirs of Fellows of the Royal Society 49 (December 2003): 179–95. https://doi.org/10.1098/rsbm.2003.0011.