Regular Core Observables

This repository contains the manuscript, public summary, code, and generated figures for a computational study of observational constraints on regular black holes and negative-pressure cores in compact objects.

The analysis focuses on three observational channels:

• black-hole ringdown and quasinormal-mode shifts
• neutron-star tidal deformability and mass-radius constraints
• gravitational-wave echoes and the extremality threshold

It also includes a Hayward-remnant calculation relevant to primordial-black-hole dark matter scenarios.

Main files

• manuscript.md: full research manuscript
• popular-summary.md: non-technical summary
• manuscript.html: HTML rendering target for the manuscript
• popular-summary.html: HTML rendering target for the public summary

Core scripts

• kerr_qnm.py: Hayward/Bardeen/Dymnikova QNM analysis and detector thresholds
• tov_tidal.py: two-fluid TOV solver with tidal deformability
• post_merger_f2.py: post-merger frequency shifts from TOV outputs
• causality_sweep.py: sound-speed consistency scan
• hayward_remnant.py: Hawking-temperature and remnant-mass calculation
• tidal_gw170817.py: GW170817 tidal-constraint plots
• conceptual_diagram.py: overview figure used in the manuscript

Reproducibility

Install dependencies:

python -m pip install -r requirements.txt

Generate the HTML outputs:

python build_manuscript_html.py
python build_popular_summary_html.py

On Windows, if python is not on PATH, use:

py build_manuscript_html.py
py build_popular_summary_html.py

Citation

Use the Zenodo version DOI for formal citation of this archived release: 10.5281/zenodo.20761280

The badge above points to the Zenodo concept DOI: 10.5281/zenodo.20737351

The concept DOI is a stable project-level landing page. The version DOI refers to this exact archived release.

BibTeX:

@software{sasadeusz_regular_core_observables_2026,
	author    = {Sasadeusz, Rafal},
	title     = {Regular Core Observables},
	version   = {v1.0.3},
	year      = {2026},
	month     = jun,
	publisher = {Zenodo},
	doi       = {10.5281/zenodo.20761280},
	url       = {https://doi.org/10.5281/zenodo.20761280}
}

Notes

• The manuscript is a phenomenological study. It does not derive the regular core from a microphysical theory.
• The slow-rotation Kerr extension is explicitly treated as first-order and is not reliable at astrophysical spins such as GW150914.
• The popular-summary files are intended for general readers; the manuscript files are the canonical research version.