Girish Kulkarni

Girish Kulkarni

I am a faculty member in the Department of Theoretical Physics of the Tata Institute of Fundamental Research (TIFR) in Mumbai, India, and the head of a partner group of the Max Planck Institute of Astronomy (MPIA) of Heidelberg, Germany.

My research is in the area of astrophysics and cosmology. I study the properties of the universe in the first billion years of its existence. Some of the questions I try to answer are how did the temperature of the universe evolve throughout the cosmic history; when and how did the first stars, black holes, and galaxies form; and what is the nature of dark matter. In my work, I collaborate closely with experimentalists as part of programmes such as SKA, REACH and XQR-30 that exploit some of the biggest current and upcoming astronomical facilities across the world.

Contact me if you are interested in doing a departmental project or a PhD thesis with me. Also get in touch if you are looking for a postdoc position to work with me, or if you would like to visit TIFR. I am currently not taking any students for masters or summer projects.


Department of Theoretical Physics
Tata Institute of Fundamental Research,
Homi Bhabha Road,
Mumbai 400005, India

Office: A323
Phone: +91 (0) 22–22782427


  • January 2020: New paper titled “Probing the thermal state of the intergalactic medium at z > 5 with the transmission spikes in high-resolution Lyα forest spectra”
  • January 2020: RFP for high-performance computing (deadline: 22 January 2020)
  • December 2019: Conference titled “Science with Subaru: An Indian Perspective
  • December 2019: New paper titled “Constraining the second half of reionization with the Lyman-β forest”
  • December 2019: New paper titled “Long troughs in the Lyman-α forest below redshift 6 due to islands of neutral hydrogen”


Nabendu Khan (departmental project student; intergalactic medium)
Shikhar Mittal (departmental project student; cosmic dawn)
Janakee Raste (postdoctoral researcher; intensity mapping)
Sreeta Roy (masters student; epoch of reionization)
Mohit Saharan (masters student; intensity mapping)
Yash Mohan Sharma (masters student; intergalactic medium)

Recent Talks

2020 January 21: “Constraints on the AGN contribution to reionization ” (“The First Billion Years of the Universe” conference, IIT Indore)

2019 December 19: “Luminosity functions and clustering of Lyman-α Emitters” (“Science with Subaru: An Indian Perspective” conference, TIFR Mumbai)

2019 November 5: “TMT Synergies for the First Billion Years of the Universe” (TMT Science Forum, Xiamen University, Xiamen, China)

2019 October 7: “Hints of a concordant reionization model from the Lyman-α Forest” (Second Global 21-cm Workshop, McGill University, Montreal, Canada)

2019 September 26: “When did reionization happen?” (APEC Seminar, Kavli Institute for the Physics and Mathematics of the Universe, Tokyo, Japan)

2019 August 6: “Recent progress towards revealing thirteen billion years of cosmic thermal history” (CAS Seminar, IIT Bombay, Mumbai, India)

2019 July 16: “Large Lyman-α opacity fluctuations in models of late reionization” (“Barefoot EoR” conference, Fitzroy Island, Australia)

2019 April 12: “When did reionization happen?” (NCRA Colloquium, NCRA-TIFR, Pune, India)

2019 January 25: “Large Lyman-α opacity fluctuations in models of late reionization” (“Cosmology: The Next Decade” Workshop, ICTS-TIFR, Bengaluru, India)

2019 January 4: “Recent progress in understanding the epoch of reionization” (Thirtieth Meeting of the IAGRG, Hyderabad, India)


2019: Mathematical Methods
2019: Numerical Methods
2020: Computational Physics