1. Centre for Theoretical Physics, Jamia Millia Islamia, New Delhi 110025, India
2. Centre for Theoretical Physics and Multidisciplinary Centre, for Advanced Research and Studies (MCARS), Jamia Millia Islamia, New Delhi 110025, India
3. Astrophysics and Cosmology Research Unit, School of Mathematics, Statistics and Computer Science, University of KwaZulu-Natal, Private Bag X54001, Durban 4000, South Africa