# On the stability of strange dwarf hybrid stars

## TL;DR

This paper examines the stability of strange dwarf hybrid stars with a density discontinuity, concluding that traditional stability criteria are valid and such stars are not stable.

## Contribution

The study provides a numerical analysis confirming that strange dwarfs with density discontinuities are unstable, challenging previous suggestions of their stability.

## Key findings

- Strange dwarfs are not stable according to numerical stability analysis.
- Conventional stability criteria based on mass-radius extrema are valid.
- Previous claims of stability for strange dwarfs are not supported by detailed calculations.

## Abstract

We investigate the stability of stars with a density discontinuity between a high-density core and a very low density mantle. Previous work on "strange dwarfs" suggested that such a discontinuity could stabilize stars that would have been classified as unstable by the conventional criteria based on extrema in the mass-radius relation. We investigate the stability of such stars by numerically solving the Sturm-Liouville equations for the lowest-energy modes of the star. We find that the conventional criteria are correct, and strange dwarfs are not stable.