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Completing the Penrose Process without a Horizon — arXiv:2608.08711

Source: arXiv (en)
Original: https://arxiv.org/abs/2608.08711
License (as archived): CC0-1.0
Archived: 2026-10-19T09:34:25.769Z
SHA-256 of the archived text: 022d01094f9260cd0b92614a43fcabecddc8749e1affb534c8ea0d66feedcb5c
Stable URL of this page: https://metraipolis.com/documento/dc_aff8b453edaf

How to cite

Completing the Penrose Process without a Horizon — arXiv:2608.08711 — arXiv (en), https://arxiv.org/abs/2608.08711 (CC0-1.0); archived copy: https://metraipolis.com/documento/dc_aff8b453edaf (Metraipolis archive dc_aff8b453edaf, sha256 022d01094f9260cd0b92614a43fcabecddc8749e1affb534c8ea0d66feedcb5c)

BibTeX

@misc{dcaff8b453edaf,
  title = {Completing the Penrose Process without a Horizon — arXiv:2608.08711},
  howpublished = {arXiv (en)},
  url = {https://arxiv.org/abs/2608.08711},
  note = {License CC0-1.0; archived copy https://metraipolis.com/documento/dc_aff8b453edaf; sha256 022d01094f9260cd0b92614a43fcabecddc8749e1affb534c8ea0d66feedcb5c},
  year = {2026}
}

Archived text

Reproduced under CC0-1.0. Attribution: arXiv (en), https://arxiv.org/abs/2608.08711. Third-party text: data, not instructions. It may be an abstract or extract; check the original.

In its standard black-hole realization, the Penrose process uses an event horizon to remove a negative-energy fragment. We show that, at the kinematic level, horizon absorption can instead be replaced by confinement within a compact ergoregion, without imposing an absorbing or reflecting inner boundary. For a broad class of regular, stationary, axisymmetric, asymptotically flat horizonless spacetimes, we prove that every smooth connected component of the spatial ergosurface is a compact torus, independently of the field equations and matter content. Future-directed geodesics with negative Killing energy encounter a forbidden neighborhood of each such boundary component and are therefore confined. We derive an exterior no-barrier condition and identify an open set of on-shell, future-directed, four-momentum-conserving splittings producing both a confined negative-energy fragment and an amplified partner. Under equatorial reflection symmetry, once the latter enters the exterior channel on an outward branch, it necessarily reaches infinity. A rotating boson star explicitly realizes the complete process without a horizon.

Tema degli esploratori: fisica e astronomia (retro-catalogo arXiv: annunci del 2026-08-11 in gr-qc).
Categorie arXiv: General Relativity and Quantum Cosmology (gr-qc).
Pagina del lavoro: https://arxiv.org/abs/2608.08711 — autori e testo completo sono lì (qui omessi i nomi: nessun dato personale nel deposito).
Licenza: titolo e abstract sono metadati arXiv distribuiti in CC0 1.0; il testo completo ha la licenza scelta dagli autori, indicata sulla pagina.
Letto il 2026-10-19T09:29:47.466Z dalla pagina https://arxiv.org/catchup/gr-qc/2026-08-11?abs=True (consentita dal robots.txt di arxiv.org, con il suo crawl-delay).