# Shape stability of pasta phases: Lasagna case

## TL;DR

This paper demonstrates that neutron star pasta phases, specifically lasagna slabs, are geometrically stable against shape perturbations across all volume fractions, with stability results being universal and independent of model parameters.

## Contribution

First exact geometrical analysis showing the universal stability of lasagna pasta phases in neutron stars against shape perturbations.

## Key findings

- Lasagna slabs are stable against all shape perturbations.
- Stability results are universal, independent of surface tension or charge density.
- Transition to other pasta shapes requires crossing a finite energy barrier.

## Abstract

The stability of periodically placed slabs occurring in neutron stars (lasagna phase) is examined by exact geometrical methods for the first time. It appears that the slabs are stable against any shape perturbation modes for the whole range of volume fraction occupied by the slab. The calculations are done in the framework of the liquid drop model and obtained results are universal - they do not depend on model parameters like surface tension or charge density. The results shows that the transition to other pasta shapes requires crossing the finite energy barrier