Since 1998, I have delivered one hundred and thirty two (132) invited lectures at sixty five (65) academic institutions spread over fifteen (15) different countries in North America, Europe and Asia. Detail list in reverse chronological order follows.

2014

1. Keynote speaker at Pantheon - 14, the annual academic and technological festival of Birla Institute of Technology, Mesra. Click here for further detail.

2012

2. Black Hole Accretion: A Dynamical Systems Approach, a two lecture series delivered at DST-SERC School on Nonlinear Dynamics, held at S. N. Bose National Centre for Basic Sciences during the period 30 November – 22 December 2012.
3. Black Hole at Your Bathtub, Colloquium at PAMU, Indian Statistical Institute, Kolkata, November, 2012.
4. A six lecture course with duration of two hours for each lecture on Emergent Gravity Phenomena in the Classical and the Quantum Fluids at Ramkrishna Mission Vivekananda University, Kolkata, India, during September - October 2012.
5. Invited speaker at the workshop Recent Aspects of Gravitation and Cosmology', organized by the relativity and Cosmology Research Centre, Department of Physics, Jadavpur University, on Axisymmetric black hole accretion as  dynamical systems: An overview', March, 2012.

2011

6. Colloquium at N. Copernicus Astronomical Institute, Warsaw, Poland, on Portrait of a dark face, September, 2011.
7. Seminar at Marian Smoluchowski Institute of Physics. Jagiellonian University, Cracow, Poland, on Black hole shadow imaging for relativistic shocked accretion, August, 2011.
8. Seminar at the Relativistic Astrophysics Group, Astronomical Institute of the Academy of Sciences, Prague, Czech Republic, on Event horizon imaging for multi-transonic flow, July, 2011.
9. Seminar at the Argelander-Institut für Astronomie, Universit${\ddot {\rm a}}$t Bonn, Germany, on Analogue gravity phenomena in astrophysics, July, 2011.
10. Colloquium at the Argelander-Institut für Astronomie, Universit${\ddot {\rm a}}$t Bonn, Germany, on Portrait of a dark face, July 2011.
11. Colloquium at Indian Association for the cultivation of sciences, Kolkata, India, on Portrait of a dark face, April, 2011.
12. Seminar at S. N. Bose National centre of basic sciences, Kolkata, India, on Black Holes at yoru bathtub, April, 2011.
13. Colloquium at S. N. Bose National Centre for Basic Sciences, Kolkata, India, on Portrait of a dark face, April, 2011.
14. Colloquium at Centre for Relativity and Cosmology, Jadavpur University, on Emergent Gravity as Analogue Model, April, 2011.
15. Seminar at Saha Institute of Nuclear Physics, Calcutta, India, on Portrait of a Dark Face, March, 2011.
16. Colloquium at Centre for Relativity and Cosmology, Jadavpur University, on The Black Hole Shadow Imaging, March 2011.

2010

17. A two lecture series at the Department of Physics, Chulalongkorn University, Bangkok, Thailand, on How to study the astrophysical accretion from a dynamical systems approach, August, 2010.
18. Colloquium at Institute of Astronomy, Academia Sinica, on On the role of black hole spin in influencing the behaviour of transonic accretion, July, 2010.
19. Lecture for Summer Students at the Institute of Astronomy, Academia Sinica, Taiwan, on Astrophysical Black Holes: Laboratories to Test the Theory of Relativity, July, 2010.
20. Computational Fluid Dynamics and Star Formation Group Seminar, ASIAA, Taiwan, on Black Hole Accretion: A Dynamical Systems Approach, July, 2010.
21. Seminar at Institute of Astronomy, National Central University, Taiwan, on Behaviour of Matter Close to the Event Horizon, July, 2010.
22. Group seminar at the Ddepartment of Earth Science and Astronomy, National Taiwan Normal University, Taiwan, on Application of the sub-Keplarian flow to the Galactic Centre black hole accretion, July, 2010.
23. Seminar at Theoretical High Energy Physics Group, Institute of Physics, Academia Sinica, Taiwan, on Emergent metric in classical and quantum fluid, June, 2010.
24. Colloquium at National Tsing Hua University, Taiwan, on Accretion onto astrophysical black holes as an Autonomous Dynamical System, June, 2010.
25. Colloquium at the Department of Physics, National Taiwan Normal University, Taiwan, on Analogue Gravity Phenomena, June, 2010.
26. Oral presentation at the Astronomical Society of the Republic of China 2010 Annual Meeting, on Behaviour of Relativistic Matter Close to the Black Hole Event Horizon, May, 2010.
27. Seminar at Circumstellar Astrophysics Meeting, Institute of Astronomy, Academia Sinica, Taiwan, on Low Angular Momentum Accretion Phenomena, May, 2010.
28. Black Holes in Astrophysics} popular lecture at Visva Bharati University, Santiniketan, India, February, 2010. \item Transonic Astrophysical Accretion, seminar at Visva Bharati University, Santiniketan, India, February, 2010.

2009

29. Public Lecture at St Xavier College, Calcutta University, on Astrophysical Black Holes, October 2009.
30. Seminar at Astronomical Institute of the Academy of Sciences of the Czech Republic (Group of Relativistic Astrophysics) in Prague, on General relativistic black hole accretion as dynamical systems, July, 2009.
31. Seminar at Marian Smoluchowski Institute of Physics. Jagiellonian University, Cracow, on Accretion onto Black Hole: A Dynamical Systems Approach, June, 2009.
32. Colloquium at N. Copernicus Astronomical Institute, Warsaw, Poland, on On the role of black hole spin in influencing the terminal behavior of accretion flow, May, 2009.
33. Seminar at University of Vienna, Vienna, Austria, on Aspects of low angular momentum relativistic accretion, May, 2009.
34. Colloquium at University of Vienna, Vienna, Austria, on Analogue Gravity in Astrophysics and Cosmology, May, 2009.
35. Colloquium at Saha Institute of Nuclear Physics, Calcutta, India, on Black hole in your bathtub, April, 2009.
36. Colloquium at Raman Research Institute, Bangalore, India, on Analogue gravity in classical fluid and in the Bose Einstein Condensate, April, 2009.
37. Colloquium at Institute of Mathematical Sciences, Chennai, on Black Hole at your Bathtub, March, 2009.
38. Seminar at Institute of Mathematical Sciences, Chennai, on Astrophysical accretion as an analogue gravity phenomena, March, 2009.
39. Colloquium at Chennai Mathematical Institute, Chennai, on Black Hole at your Bathtub, March, 2009.
40. Seminar at Institute of Mathematical Sciences, Chennai, on Accreting black hole as an analogue gravity model, March, 2009.
41. Public Lecture organized by Navakarnataka Publications, at National College Bangalore, on Astrophysical Black Hole, a Current Perspective, January, 2009.
42. Seminar at Indian Institute of Science, Bangalore, on Simulating Astrophysical and Cosmological Spacetime in Classical and Quantum Fluid, January, 2009.

2008

43. Invited lecture on the occasion to celebrate 100 years of Physics Department of Vidyasagar College on Astrophysical Black Holes: Laboratory to Test the Theory of Relativity, December, 2008.
44. Seminar at Indian Institute of Astrophysics, Bangalore, on Astrophysical Accretion as Analogue Gravity Phenomena, October, 2008.
45. Special lecture at Indian Institute of Astrophysics, Bangalore, on Back Holes in Your Bathtub , October, 2008.
46. Public lecture at SSGC (Summer School on Gravitation & Cosmology, held at HRI) on Emergent Spacetime in Classical & Quantum Flow.
47. Lecture course at Department of Physics, Faculty of Science, Chulalongkorn University, Bangkok, Thailand, on Analogue gravity in classical and quantum fluid.
48. Colloquium at the Astronomy Department, National Central University, Taiwan, on Black Hole Analogues in Astrophysics & Cosmology.
49. Seminar at the Physics Department, National Central University, Taiwan, on Acoustic Black Holes.
50. Seminar at the Physics Department, National Chiao Tung University, Taiwan, on Analogue Hawking Radiation.
51. Seminar at Institute of Astronomy, Academia Sinica, Taipei, Taiwan, on Analogue Black Hole.
52. Seminar at Relativity & Cosmology Research Centre, Jadavpur University, Calcutta, on Analogue Gravity in Astrophysics.

2007

53. Seminar at Institute of Theoretical Physics, Charles University, Prague, Czech Republic, on General relativistic axisymmetric black hole accretion.
54. Seminar at Astronomical Institute of the Academy of Sciences of the Czech Republic (Group of Relativistic Astrophysics) in Prague, on Analogue Gravity Effects in Black Hole Astrophysics.
55. Seminar at Instytut Fizyki, Universytet Szczecinski, Szczecin, Poland, on Analogue Gravity Models.
56. Seminar at N. Copernicus Astronomical Institute, Warsaw, Poland, on Analogue Gravity Phenomena.
57. Seminar at Marian Smoluchowski Institute of Physics. Jagiellonian University, Cracow, Poland, on Black Hole Analogue.
58. Is Violation of Newton's Second Law Possible?, Journal Club Review Talk at HRI.
59. Seminar at HRI, on Analogue Gravity Phenomena.
60. Colloquium at Presidency College, Calcutta, on Accretion processes onto astrophysical black holes.
61. Seminar at Presidency College, Calcutta, on Table-top Black Holes.
62. Seminar at Indian Association for the Cultivation of Science, India, on Black Holes in a Bathtub.

2006

63. Black hole accretion as dynamical systems, a multi-lecture course in the Third SERC School on Non-linear Dynamics, December 2006, held at Indian Association for Cultivation of Science, Calcutta, India.
64. Orientation course on On the current trend in research in astrophysical science, at Burdwan University, Burdwan, India.
65. Popular science lecture on What is black hole accretion?, at Burdwan University, Burdwan, India.
66. Popular science lecture on Astrophysics around black hole, at Visva Bharati University, Shantiniketan, India.
67. Journal club review talk at HRI, India, on See a black hole on a shoestring.
68. Colloquium at Physical Research Laboratory, Ahmedabad, India, on Transonic Properties of Relativistic Accretion.
69. Colloquium at National Central University, Taiwan, on Black Hole Astrophysics.
70. Seminar at Academia Sinica, Taiwan, on Dependence of relativistic accretion on black hole spin.
71. Colloquium at Academia Sinica, Taiwan on Transonic properties of astrophysical accretion.
72. Oral presentation at the workshop Radiation and Plasma Processes in Stellar Astrophysics, TIARA, Taiwan, on Shock formation in accretion disc and related phenomena.
73. Colloquium at National Tsing Hua University, Taiwan, on Astrophysical black holes: Natural laboratory to study the special and the general theory of relativity.
74. Colloquium at Delhi University, Delhi, India, on Astrophysical black holes: Natural Laboratory to study the theory of relativity.
75. Seminar at Delhi University, Delhi, India, on Transonic properties of general relativistic black hole accretion.
76. Seminar on On Transonic black hole accretion and related phenomena, at HRI, on the occasion of a three day faculty talk.
77. A two lecture series on Computational Astrophysics, in Academic Stuff College Meeting' at Burdwan University, Burdwan, West Bengal, India.

2005

78. Guest lecturer for the course Differential geometry & general theory of relativity taught at SERC school. Took twenty seven (27) classes, each of which with duration one hour and fifteen minutes.
79. Journal club review talk at Harish Chandra Research Institute, Allahabad, India. on Steady shocks around black holes produced by sub-keplerian flows with negative energy.
80. Orientation lecture delivered to the under-graduate and the post-graduate students of Department of Physics, Burdwan University, on Research in astrophysical sciences: Pre-requisite, methodology, and the career prospects.
81. Colloquium at Burdwan University, Burdwan, West Bengal, India, on Astrophysical black holes: Laboratory to study the special and the general theory of relativity.
82. A set of three lecture course at Workshop on Fluid Dynamics', held at Indian Association of Cultivation of Science, Jadavpur, Calcutta, India, on Application of fluid dynamics in astrophysics.
83. Colloquium at Indian Association of Cultivation of Science, Jadavpur, Calcutta, India, on Astrophysical black holes: Laboratory to study the special and the general theory of relativity.
84. Seminar at Indian Association of Cultivation of Science, Jadavpur, Calcutta, India, on Transonic behaviour of general relativistic black hole accretion and its dependence on the black hole spin.
85. Seminar at Centre for Relativity & Cosmology, Jadavpur University, Kolkata, India, on Behaviour of matter close to the event horizon.
86. Seminar at Centre for Theoretical Studies, Indian Institute of Technology, Kharagpur, India, on Basics of relativistic transonic accretion.
87. Seminar at Saha Institute of Nuclear Physics, Calcutta, India, on Transonic behaviour of matter close to the event horizon.
88. Seminar at Tata Institute of Fundamental Research, India, on Formation and growth of supermassive black holes.
89. Conference talk at HRI, India, on Superluminal motion in astrophysical jets.
90. Journal club review talk at HRI, India, on Spin, Accretion, and the Cosmological Growth of Supermassive Black Holes.

2004

91. Colloquium} at N. Copernicus Astronomical Institute, Warsaw, Poland, on Behaviour of matter close to the event horizon. May, 2004.
92. Aspects of transonic black hole accretion. Colloquium presented at Raman Research Institute, Bangalore, India. Feb, 2004.
93. Behaviour of matter close to the event horizon. Colloquium presented at Indian Institute of Science, Bangalore, India. Feb, 2004.
94. Public Lecture at Burdwan University, India, on Astrophysics of Active Galactive Nuclei. Feb. 2004.

2003

95. Colloquium at Stanford University, on General Relativistic Black Hole Accretion. May, 2003.
96. Seminar at University of California, Santa Barbara, & Kavli Institute of Physics, on Shock Formation in Black Hole Accretion and Related Outflow. October, 2003.
97. Colloquium at University of British Columbia. July, 2003.
98. Seminar at University of California Los Angeles , on Dynamics of General Relativistic Black Hole Accretion Discs. May, 2003.
99. Behaviour of matter close to the event horizon. Colloquium presented at Mehta Rsearch Institute, Allahabad, India, Dec, 2003.
100. Shock formation in general relativistic black hole accretion discs. Seminar presented at Physical Rsearch Laboratory, Ahmedabad, India. Dec, 2003.
101. SMBH: The cosmic power generator. Colloquiium presented at Physical Research Laboratory, Ahmedabad, India. Dec, 2003.

2002

102. Seminar at Racah Institute of Physics, The Hebrew University of Jerusalem, Israel, on Shock formation in black hole accretion and related phenomena.
103. Black hole accretion and related phenomena. Colloquium presented at Department of Physics and Astrophysics, University of Delhi, Delhi, India.
104. How massive BHs feed the AGNs. Colloquium presented at the Indian Institute of Technology, Kanpur, India.
105. Shock formation in BH accretion and related phenomena. Seminar presented at the Indian Institute of Technology, Kanpur, India.
106. The Monster in the middle and his smoking gun: How massive black holes fuel the cosmic power-houses. Public Lecture presented on IUCAA Science Day Event.
107. On the formation of accretion powered galactic and extra-galactic jets. Colloquium presented at the Astronomy Department, Osmania University, Hyderabad.
108. Shock formation in black hole accretion and related phenomena. Seminar presented at the Astronomy Department, Osmania University, Hyderabad.
109. On the formation of accretion powered galactic and extra-galactic jets. TPSC Lecture presented at the School of Physics, Hyderabad Central University, Hyderabad.

2001

110. Colloquium at Astrophysics Department, Blacket Laboratory, Imperial College of Science & Technology, London, UK, on On some aspects of relativistic outflows.
111. Seminar at School of Mathematical Sciences, Astronomy Unit, Queen Mary & Westfield College, University of London, UK, on Accretion processes around black holes and related phenomena.
112. Accretion and Outflow around Massive Black Holes. Colloquium presented at Jadavpur University, Calcutta.
113. On the formation of accretion powered extra-galactic radio jets. Colloquium presented at Indian Institute of Science, Bangalore.
114. Accretion and Outflows around compact astrophysical objects. School of Physical Sciences, Jawaharlal Nehru University, Delhi, India.
115. The Hole, the Disc and the Jet: A Coexisting Trio at the Centre of Active Galaxies? School of Physics and Astrophysics, Pt. Ravishankar Shukla University, India. August, 2001.
116. Shocks in black hole accretion discs. Seminar at School of Physics and Astrophysics, Pt. Ravishankar Shukla University, India.
117. Expulsive and Propulsive; What are They? A Public Lecture on Astrophysical Jets presented at Gujarat University, Ahmedabad, Gujarat.

2000

118. Zeldovich Memorial Seminar at Sternberg astronomical Institute, Moscow state University, Moscow, Russia, on `High energetic astrophysical processes around accreting supermassive black holes.
119. Colloquium at Institute of Astronomy, University of Cambridge, Cambridge, UK, on On the formation of accretion-powered galactic and extra-galactic jets.
120. Colloquium at Jodrell Bank Observatory University of Manchester, Manchester, UK, on Outflows from rotating and non-rotating accretion onto black holes and neutron stars.
121. Colloquium at DAEC & UMR 8631 du CNRS, Observatorie de Paris-Meudon, Meudon, France, on Accretion and winds around compact astrophysical objects.
122. Seminar at Observatorio Astron\363mico Nacional, Alcal\341 de Henares, Alcala, Spain, on Global Inflow-Outflow solution for extragalactic jet sources.
123. Oral presentation at Third Microquasar Workshop: Granada Workshop on galactic relativistic jet sources, Granada, Spain on On the Formation of Accretion-powered Galactic and Extra-galactic Outflows.
124. Accretion Powered Extragalactic Jets. Colloquium presented at Indian Institute of Astrophysics (IIAP). Bangalore.

1999

Modelling the Origin of Astrophysical Outflows from Galactic and Extra-Galactic Sources Powered by Compact Objects. Seminar presented at Tata Institute of Fundamental Research (TIFR).
125. On the Formation of Extra-Galactic Cosmic Jets. Talk given at Young Physicists' Colloquium. Saha Institute of Nuclear Physics. Calcutta. India.
126. Astrophysical Jets: I & II. Review talk given at the workshop Young Astro-physicists of Todays India. Calcutta. On the Mass Outflow from Matter Accreting onto Compact Objects at Inter University Centre for Astronomy and Astrophysics (IUCAA), Puna. March. 1999.

1998

127. Fall Colloquium at Nicolaus Copernicus Astronomical Center, Warsaw, Poland, on Mathematical Analysis of Mass Outflow from Relativistic Accretion onto Compact Objects.
128. Colloquium at Max Planck Institute For Radioastronomie, Bonn, Germany, on On the Fate of Matter Rushing Towards Compact Objects.
129. Michaelmas Term Colloquium at the Astrophysics Department, University of Oxford, Oxford, UK, on Formation and Dynamics of Mass Outflow from Relativistic Matter Accreting onto Galactic and Extragalactic Black Holes: A New Approach to Combine Inflow-Outflow Topologies.
130. Presented two posters in 19th Texas symposium on Relativistic Astrophysics & Cosmology. Paris. France.
131. Invited talk at Dacca University, Dacca, Bangladesh on Outflow from Relativistically Accreting Matter.
132. Netscaping and Home Page Making at S. N. Bose National Centre For Basic Sciences, Calcutta.
133. The Role of Internet on Mass Education. International Workshop on Computer and Communication Technology in Education. Calcutta.
134. Computation of Outflow Rates From The Advective Accretion Disks Around Galactic And Extra Galactic Black Holes. International Conference On The Observational Evidences For Black Holes in the Universe. Calcutta.