PreprintCC BY-NC-ND 4.0arXiv
Comment on "Effect of perfect fluid dark matter..." [Phys. Dark Univ. 34 (2021) 100891]
Abstract
This Comment clarifies the physical interpretation of the black hole spacetime metric employed by Shaymatov \textit{et al.} [Phys. Dark Univ. 34 (2021) 100891]. We point out that the metric, originally derived in Li and Yang (2012), describes a specific dual-component system consisting of cold dark matter and a phantom field background. Treating this geometry as a single-component ``Perfect Fluid Dark Matter'' (PFDM) with a total equation of state wtotal = −1 is physically incompatible with the gravitational attraction required for dark matter halos. Furthermore, we clarify the distinct parameter regimes of the original model to prevent potential misapplications in extreme astrophysical scenarios.
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BibTeX
@misc{li2026comment,
title = {{Comment on "Effect of perfect fluid dark matter..." [Phys. Dark Univ. 34 (2021) 100891]}},
author = {Ming-Hsun Li and Kwei-Chou Yang},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.34019},
eprint = {2610.34019},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.34019},
note = {CC BY-NC-ND 4.0},
}
RIS
TY - UNPB
TI - Comment on "Effect of perfect fluid dark matter..." [Phys. Dark Univ. 34 (2021) 100891]
AU - Ming-Hsun Li
AU - Kwei-Chou Yang
PY - 2026
DA - 2026/10/25
PB - arXiv
DO - 10.48550/arxiv.2610.34019
UR - https://arxiv.org/abs/2610.34019
AB - This Comment clarifies the physical interpretation of the black hole spacetime metric employed by Shaymatov \textit{et al.} [Phys. Dark Univ. 34 (2021) 100891]. We point out that the metric, originally derived in Li and Yang (2012), describes a specific dual-component system consisting of cold dark matter and a phantom field background. Treating this geometry as a single-component ``Perfect Fluid Dark Matter'' (PFDM) with a total equation of state w_total = −1 is physically incompatible with the gravitational attraction required for dark matter halos. Furthermore, we clarify the distinct parameter regimes of the original model to prevent potential misapplications in extreme astrophysical scenarios.
ER -