Can an Einasto Dark-Matter Halo Support a Traversable Wormhole?

Alp Cesur

doi:10.53941/ijgtp.2026.100020

Abstract

We revisit and extend the proposal that an Einasto dark-matter halo can support a traversable wormhole [B. Sen, Can. J. Phys. 96, 1242–1245 (2018)]. Although the corresponding Einstein equations can be integrated exactly, the density profile fixes only part of the geometry: the boundary condition distinguishes a regular halo from a spacetime in which a throat has been imposed. We give a dimensionally consistent reconstruction and identify algebraic, normalization and unit inconsistencies in the original treatment. For realistic halo parameters, the geometrical deformation remains far too weak to form a throat. Treating the density and rotation curve consistently also yields pressures too small to provide the exotic stress required by a traversable wormhole. A wormhole geometry requires an additional throat-supporting contribution whose influence on galactic motion depends on the associated redshift function. We illustrate these results using the SPARC rotation curve of NGC 3198. The regular halo remains safely in the weak-field regime and contains no halo-generated throat. Under a localized-support interpretation, the data restrict a possible throat to approximately astronomical-unit scales, subject to spherical symmetry and the adopted stellar model. Exact Einasto-dressed wormholes are therefore mathematically admissible, but ordinary Einasto dark matter does not itself generate the throat.

References

1.
Morris, M.S.; Thorne, K.S. Wormholes in Spacetime and Their Use for Interstellar Travel: A Tool for Teaching General Relativity. Am. J. Phys. 1988, 56, 395–412. https://doi.org/10.1119/1.15620.
2.
Visser, M. Lorentzian Wormholes: From Einstein to Hawking; AIP Press: Woodbury, NY, USA, 1995.
3.
Hochberg, D.; Visser, M. Null Energy Condition in Dynamic Wormholes. Phys. Rev. Lett. 1998, 81, 746–749. https://doi.org/10.1103/physrevlett.81.746.
4.
Navarro, J.F.; Frenk, C.S.; White, S.D.M. The Structure of Cold Dark Matter Halos. Astrophys. J. 1996, 462, 563–575. https://doi.org/10.1086/177173.
5.
Merritt, D.; Graham, A.W.; Moore, B.; et al. Empirical Models for Dark Matter Halos. I. Nonparametric Construction of Density Profiles and Comparison with Parametric Models. Astron. J. 2006, 132, 2685–2700. https://doi.org/10.1086/508988.
6.
Retana‑Montenegro, E.; Van Hese, E.; Gentile, G.; et al. Analytical Properties of Einasto Dark Matter Haloes. Astron. Astrophys. 2012, 540, A70. https://doi.org/10.1051/0004‑6361/201118543.
7.
Kuhfittig, P.K.F. Gravitational Lensing of Wormholes in the Galactic Halo Region. Eur. Phys. J. C 2014, 74, 2818. https://doi.org/10.1140/epjc/s10052‑014‑2818‑2.
8.
Rahaman, F.; Salucci, P.; Kuhfittig, P.K.F.; et al. Possible Existence of Wormholes in the Central Regions of Halos. Ann. Phys. 2014, 350, 561–567. https://doi.org/10.1016/j.aop.2014.08.003.
9.
Rahaman, F.; Shit, G.C.; Sen, B. Could Wormholes Form in Dark Matter Galactic Halos? Astrophys. Space Sci. 2016, 361, 37. https://doi.org/10.1007/s10509‑015‑2626‑7.
10.
Sen, B. Existence of Wormhole Supported by the Einasto Density Profile. Can. J. Phys. 2018, 96, 1242–1245. https://doi.org/10.1139/cjp‑2017‑0524.
11.
Xu, Z.; Tang, M.; Cao, G.; et al. Possibility of Traversable Wormhole Formation in the Dark Matter Halo with Isotropic Pressure. Eur. Phys. J. C 2020, 80, 70. https://doi.org/10.1140/epjc/s10052‑020‑7636‑0.
12.
Rahaman, F.; Samanta, B.; Sarkar, N.; et al. Traversable Wormholes Supported by Dark Matter and Monopoles with Semiclassical Effects. Eur. Phys. J. C 2023, 83, 395. https://doi.org/10.1140/epjc/s10052‑023‑11456‑4.
13.
Yousaf, Z.; Bhatti, M.Z.; Rizwan, M.; et al. From Dark Halos to Exotic Bridges: Wormhole Structures with Einasto Density Profiles. Nucl. Phys. B 2025, 1019, 117128. https://doi.org/10.1016/j.nuclphysb.2025.117128.
14.
Albalahi, A.M.; Yousaf, Z.; Rizwan, M.; et al. Constructing TraversableWormholes in Dark Matter Halos with a Non‑Trivial Redshift Function. Eur. Phys. J. C 2026, 86, 142. https://doi.org/10.1140/epjc/s10052‑026‑15386‑9.
15.
Ray, S.; Sanyal, A. Traversable Wormhole Geometry Reconstruction from the Rotation Curve of NGC 3198: A Comparative Study of Dark Matter Halo Profiles. arXiv 2026, arXiv:2605.20221.
16.
Lelli, F.; McGaugh, S.S.; Schombert, J.M. SPARC: Mass Models for 175 Disk Galaxies with Spitzer Photometry and Accurate Rotation Curves. Astron. J. 2016, 152, 157. https://doi.org/10.3847/0004‑6256/152/6/157.
17.
Karukes, E.V.; Salucci, P.; Gentile, G. The Dark Matter Distribution in the Spiral NGC 3198 out to 0.22RVir. Astron. Astrophys. 2015, 578, A13. https://doi.org/10.1051/0004‑6361/201425339.
18.
Konoplya, R.A.; Molina, C. RingingWormholes. Phys. Rev. D 2005, 71, 124009. https://doi.org/10.1103/physrevd.71.124009.
19.
Bronnikov, K.A.; Konoplya, R.A.; Zhidenko, A. Instabilities of Wormholes and Regular Black Holes Supported by a Phantom Scalar Field. Phys. Rev. D 2012, 86, 024028. https://doi.org/10.1103/physrevd.86.024028.
20.
Armendáriz‑Picón, C. On a Class of Stable, Traversable Lorentzian Wormholes in Classical General Relativity. Phys. Rev. D 2002, 65, 104010. https://doi.org/10.1103/physrevd.65.104010.
21.
Shinkai, H.A.; Hayward, S.A. Fate of the First Traversible Wormhole: Black‑Hole Collapse or Inflationary Expansion. Phys. Rev. D 2002, 66, 044005. https://doi.org/10.1103/physrevd.66.044005.
22.
González, J.A.; Guzmán, F.S.; Sarbach, O. Instability of Wormholes Supported by a Ghost Scalar Field: I. Linear Stability Analysis. Class. Quantum Grav. 2009, 26, 015010. https://doi.org/10.1088/0264‑9381/26/1/015010.
23.
Cremona, F.; Pirotta, F.; Pizzocchero, L. On the Linear Instability of the Ellis–Bronnikov–Morris–Thorne Wormhole. Gen. Relativ. Gravit. 2019, 51, 19. https://doi.org/10.1007/s10714‑019‑2501‑x.

Scilight Press

Author Information

Abstract

Keywords

References

About Scilight

Journals

Publishing Policies

Contact Us