  Magnetic reconnections (MRs) for various magnetic field line (MFL) topologies
are believed to be the initiators of various solar eruptive events like flares
and coronal mass ejections (CMEs). Consequently, important is a thorough
understanding and quantification of the MFL topology and their evolution which
leads to MRs. Contemporary standard is to extrapolate the coronal MFLs using
equilibrium models where the Lorentz force on the coronal plasma is zero
everywhere, because either there is no current or the current is parallel to
the magnetic field. In tandem, a non-force-free-field (NFFF) extrapolation
scheme has evolved and allows for a Lorentz force which is non-zero only at the
photosphere but asymptotically vanishes with height. The paper reports
magnetohydrodynamic (MHD)- simulations initiated by NFFF extrapolation of the
coronal MFLs for the active region NOAA 11158. Interestingly, quasi-separatrix
layers (QSLs) which facilitate MRs are detected in the extrapolated MFLs. The
AR 11158 is flare producing and, the paper makes an attempt to asses the role
of QSLs in the flare onsets.
