Sarojini Naidu College for Women

Affiliated to West Bengal State University

Govt Sponsored, Estd. 1956, UGC

NAAC Re-accredited with Grade "A" (3rd Cycle)

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Dr. Sankhasubhra Nag

Dr. Sankhasubhra Nag


Designation:  Associate Professor

Qualification:  M.Sc., Ph. D.

Teaching Experience:

    Full time commitments:

  • 17 years in Sarojini Naidu College for Women, Kolkata at UG level.
  • 1 year in St. Xavier’s College, Kolkata at both UG & PG level.

     Guest assignments:

  • 1 year in Presidency College, Kolkata at PG level.
  • 4 semesters  in St. Xavier’s College, Kolkata at PG level.
  • 14 semesters in CAPSS, Bose Institute, Kolkata at PG level.
  • 14 semesters in West Bengal State University, Barasat at PG level.
  • 1 semester in Lady Brabourne College, Kolkata at PG level.

Current Teaching Modules/Topics:

UG level

Course 1st year 2nd year 3rd year
Honours Thermal Physics (CC6) [Theory & Prac]

Mathematical Physics III (CC8) [Theory & Prac]

Computational Physics Skill (SEC2) [Mixed]

Advanced Mathematical Physics I (ADSE1) [Theory & Prac]
General

 

PG level (Guest Assignments)

  • Odd  semesters:       Astrophysics I (at WBSU).
  • Even semesters:      Nonlinear Dynamics (at WBSU).

Research Experience:

  • 6 years as JRF/SRF at Saha Institute of Nuclear Physics, Kolkata in Ph.D. program
  • 12 years as Lecturer/ Assistant Professor in UG Colleges along  with full time teaching.
  • Principal Investigator of the completed UGC Minor Research Project (Sanction No. F. PSW — 163/13-14).

Area of Research:

  • Quantum Chaos
  • Quantum Entanglement generation and Quantum Decoherence
  • Black Hole Accretion in Astrophysics

Other Academic Interests:

  • Nonlinear Dynamics
  • Mathematical Biology
  • Quantum Information
  • Chaos in Astrophysics
PublicationsPresentationsOther Academic Contributions
  1. Pratik Tarafdar, Deepika A. Bollimpalli, Sankhasubhra Nag, Tapas K. Das. “Influence of geometrical configuration on low angular momentum relativistic accretion around rotating black holes”. Phys. Rev. D, 100, August 2019, 043024.

  2. Md Arif Shaikh, Susovan Maity, Sankhasubhra Nag, Tapas Kumar Das. “Effective sound speed in relativistic accretion discs around Schwarzschild black holes”. New Astronomy, 69, May 2019, Pages 48-57.

  3. Supriyo Majumder, Sankhasubhra Nag, Tapas K. Das. “Low angular momentum accretion of fractal medium on to Kerr black holes and the emergence of the acoustic manifold”. Monthly Notices of the Royal Astronomical Society, 480, Issue 3, November 2018, Pages 3017–3030.

  4. Sankhasubhra Nag, Siddhartha Sinha, Deepika B. Ananda, Tapas K. Das. “Influence of the black hole spin on the chaotic particle dynamics within a dipolar halo”. Astrophysics and Space Science, 362, Issue 4, article id.81, 8 pp.

  5. Sonali Saha, Sharmistha Sen, Sankhasubhra Nag, Suparna Raychowdhury, Tapas K. Das. “Model dependence of the multi-transonic behaviour, stability properties and the corresponding acoustic geometry for accretion onto rotating black holes“. New Astronomy, 43, February 2016, Pages 10–21.
  6. Tapas K Das, Sankhasubhra Nag, Swathi Hegde, Sourav Bhattacharya, Ishita Maity, Bożena Czerny, Paramita Barai, Paul J Wiita, Vladimír Karas, Tapan Naskar. “Black hole spin dependence of general relativistic multi-transonic accretion close to the horizon“. New Astronomy, 37, May 2015, Pages 81–104. [Highlighted in Nature Asia]
  7. Sankhasubhra Nag, Deepika B. Ananda, Ishita Maity, Tapas K. Das. “Development of Secular Instability in Different Disc Models of Black Hole Accretion“. Proc Indian Natn Sci Acad, 81,No. 1, February Special Issue 2015 pp. 267–271
  8. Sankhasubhra Nag. “Environment Induced Decoherence of  System with Two Qubits Interacting with Heisenberg Hamiltonian”. Proc. Nat. Conf. on Quantum Correlations: Foundations and Applications, Eds. D. Home, G. Kar, D. Banerjee. March 2014.
  9. Neven Bilić, Arpita Choudhary, Tapas K Das, Sankhasubhra Nag. “The role of axisymmetric flow configuration in the estimation of the analogue surface gravity and related Hawking like temperature“. Class. Quant. Gravity, 31, February 2014 Number 3, 035002 
  10. Shilpi Agarwal, Tapas K. Das, Rukmini Dey, Sankhasubhra Nag.”An analytical study on the multi-critical behaviour and related bifurcation phenomena for relativistic black hole accretion“.  Gen. Rel. Grav., 44, July 2012, Pages 1637–1655
  11. Sankhasubhra Nag, Swagata Acharya, Arnab K. Ray, Tapas K. Das. “The role of flow geometry in influencing the stability criteria for low angular momentum axisymmetric black hole accretion“. New Astronomy, 17, April 2012, Pages 285–295
  12. Avijit Lahiri, Gautam Ghosh, Sankhasubhra Nag. “Mixing and Decoherence to Nearest Separable States“. Int. J. Quantum Inform. 07, June 2009, No. 04, Pages 829-846
  13. Sankhasubhra Nag, Gautam Ghosh, Avijit Lahiri. “Quantum chaos: Reduced density matrix fluctuations in coupled systems“. Physica D, 204, 1 May 2005, Pages 110–121
  14. Sankhasubhra Nag, Avijit Lahiri, Gautam Ghosh. “Study of Coupled Systems in Search of Quantum Signature of Chaos“. Proc. of the Second National Conference on Nonlinear Systems and Dynamics, February 2005, Aligarh Muslim University, Pages 97
  15. Sankhasubhra Nag, Gautam Ghosh, Avijit Lahiri. “Signatures of quantum chaos in the reduced density matrix of subsystems“. Proc. of the First National Conference on Nonlinear Systems and Dynamics, December 2003, IIT Kharagpur, Pages 53
  16. Avijit Lahiri, Sankhasubhra Nag. “Dynamical manifestation of quantum chaos: density matrix fluctuations in subsystems“. Physics Letters A, 318, November 2003, Pages 6–14
  17. Sankhasubhra Nag, Avijit Lahiri, Gautam Ghosh. “Entropy production due to coupling to a heat bath in the kicked rotor problem“. Physics Letters A, 292, December 2001, Pages 43–48
  1. Oral presentation in the National Conference in Nonlinear Systems & Dynamics, 2003 at IIT, Kharagpur.
  2. Oral presentation in the National Conference in Nonlinear Systems & Dynamics, 2005 at Aligarh Muslim University, Aligarh.
  3. Delivered HRI Colloquium in 2009 at HRI, Allahabad.
  4. Invited lecture in the National level Seminar on Theoretical Techniques for Disordered Systems in 2009 at Condensed Matter Research Centre, Jadavpur University.
  5. Invited talk in the National Seminar on Interdisciplinary Problems in Non-linear Dynamics: Computational and Other Techniques in 2010 at Department of Applied Mathematics, Calcutta University.
  6. Invited speaker in the Workshop on Green’s Function and Some Applications organized by Indian Society for Nonlinear Analysts in 2010 at S N Bose National Centre for Basic Sciences,Kolkata.
  7. Special institution level Lecture on Overview on Nonlinear Dynamics in 2010 at St. Xavier’s College, Kolkata.
  8. Poster presentation in the International Conference on Quantum Information Processing and Applications in 2011 at HRI, Allahabad.
  9. Invited talk in the National Seminar on Differential Equations: Modelling,Analysis and Computation in 2011 at Department of Applied Mathematics, Calcutta University.
  10. Oral presentation in the National Seminar on Quantum Mechanics: Inception, Evolution & Future in 2011 at Narasingha Dutta College, Howrah.
  11. Oral presentation in the National Seminar on Recent Advances in Techniques of Applied Mathematics: Computational and Analytical in 2012 at Department of Applied Mathematics, CalcuttaUniversity.
  12. Oral presentation in the State level Seminar on Astrophysics in 2013 at RKMVC College, Rahara.
  13. Presentation (paper accepted but could not attend) submitted in the International Conference on Quantum Information Processing and Applications in 2013 at HRI, Allahabad.
  14. Poster presentation in the International Conference on Matter at Extreme Conditions: Then & Now in 2014 at Bose Institute, Kolkata.
  15. Oral presentation in the International Conference on Emerging Trends of Applied Mathematics in 2014 at Department of Applied Mathematics, Calcutta University.
  16. Oral presentation in International Conference on Modern Trends in Social and Basic Sciences in 2015 at Alipurduar College, Alipurduar, North Bengal.
  1. Invited and Participated at the national level Physics Olympiad Camp at HBCSE, TIFR, Mumbai in March 2010 and was again invited for the Resource Generation camp for the Physics Olympiad thereheld in September, 2010.
  2. Served as one of the Examiners for NGPE, 2010 Examination (Stage III).
  3. Served as one of the Judges/Evaluators of the project evaluation programs, 2011 of the JBNSTS scholars during their association with JBNSTS.
  4. Served as Paper Setter/ Moderator for different Universities/ Autonomous Institutions both UG & PG level examinations.