**Mahan Mj** (Bengali: মহান মহারাজ)), (born Mahan Mitra (Bengali: মহান মিত্র), 5 April 1968 ), also known as **Mahan Maharaj** and **Swami Vidyanathananda** (Bengali: স্বামী বিদ্যানাথানন্দ), is an Indian mathematician and monk of the Ramakrishna Order. He is a recipient of the 2011 Shanti Swarup Bhatnagar Award in Mathematical Sciences. and the Infosys Prize 2015 for Mathematical Sciences. He is best known for his work in hyperbolic geometry, geometric group theory, low-dimensional topology and complex geometry.

Mahan Mitra studied at St. Xavier's Collegiate School, Calcutta, till Class XII. He then entered the Indian Institute of Technology Kanpur, with an AIR (All India Rank) rank of 67 in the Joint Entrance Examination, where he initially chose to study electrical engineering but later switched to mathematics. He graduated with a Masters in mathematics from IIT Kanpur in 1992.

Mahan Mitra joined the PhD program in mathematics at University of California, Berkeley with Andrew Casson as his advisor. He received the Earle C. Anthony Fellowship, U.C. Berkeley in 1992–1993 and the prestigious Sloan Fellowship for 1996–1997. After earning a doctorate from the University of California at Berkeley in 1997, he worked briefly at the Institute of Mathematical Sciences in 1998. Spiritually inclined, he joined the Ramakrishna Math as a renunciate upon being impressed by the life and work of the Vedantic philosopher Ramakrishna Paramahansa. His initial name was Brahmachari BrahmaChaitanya. He was renamed as Swami Vidyanathananda after receiving his saffron robe in 2008. Swami Vidyanathananda is a monk at the order's headquarters at Belur Math. He was Professor of Mathematics and Dean of Research at the Ramakrishna Mission Vivekananda University till 2015. He is currently Professor of Mathematics at Tata Institute of Fundamental Research Mumbai .

He has widely published and presented his research in the area of hyperbolic manifolds and ending lamination spaces. His most notable work is the proof of existence of Cannon–Thurston maps,. This led to the resolution of the conjecture that connected limit sets of finitely generated Kleinian groups are locally connected. He is also the author of a book titled *Maps on boundaries of hyperbolic metric spaces*.

Mahan Maharaj, as he is known to his students and colleagues, is fluent in English, Hindi and Bengali. He also knows a bit of Tamil, learnt from his stay in southern part of India at IMSc. He has been quoted as saying "I am enjoying being a monk as much as I enjoy my mathematics".