arXiv subjects

Niranjana Kulkarni

Publications and source records attributed to Niranjana Kulkarni.

2 recordsLinked to original sources

arXiv2025

Stable bi-frequency spinor modes as Dark Matter candidates

We show that spinor systems with scalar self-interaction, such as the Dirac--Klein--Gordon system with Yukawa coupling or the Soler model, generically have bi-frequency solitary wave solutions. We develop the approach to stability properties of such waves and use the radial reduction to show that indeed the (linear) stability is available for a wide range of parameters. We show that only bi-frequency modes can be dynamically stable and suggest that stable bi-frequency modes can serve as storages of the Dark Matter. The approach is based on linear stability results of one-frequency solitary waves in (3+1)D Soler model, which we obtain as a by-product.

math.AP↗

arXiv2024

On spectral stability of one- and bi-frequency solitary waves in Soler model in (3+1)D

For the nonlinear Dirac equation with scalar self-interaction (the Soler model) in three spatial dimensions, we consider the linearization at solitary wave solutions and find the invariant spaces which correspond to different spherical harmonics, thus achieving the radial reduction of the spectral stability analysis. We apply the same technique to the bi-frequency solitary waves (which are generically present in the Soler model) and show that they can also possess linear stability properties similar to those of one-frequency solitary waves.

math.AP↗