{"ID":23577918,"CreatedAt":"2026-09-18T05:07:30.921092366Z","UpdatedAt":"2026-09-18T05:07:30.921092366Z","DeletedAt":null,"paper_url":"https://arxiv.org/abs/2609.20626","arxiv_id":"2609.20626","title":"On the Extended Kerr-Newman-Bertotti-Robinson Spacetime: Two Black Holes and a Naked Singularity in Bertotti-Robinson Universe","abstract":"We introduce new coordinates that extend the Kerr--Newman--Bertotti--Robinson spacetime consistently with the previous reciprocal continuation. In these coordinates, the two points at $Ω=0$ are resolved into complete Bertotti--Robinson null infinities. The extended spacetime describes two black holes sharing a common exterior of nontrivial topology, together with a naked ring singularity. In the regular static limit, the new coordinates globally identify the spacetime with the balanced Alekseev--García geometry.","short_abstract":"We introduce new coordinates that extend the Kerr--Newman--Bertotti--Robinson spacetime consistently with the previous reciprocal continuation. In these coordinates, the two points at $Ω=0$ are resolved into complete Bertotti--Robinson null infinities. The extended spacetime describes two black holes sharing a common e...","url_abs":"https://arxiv.org/abs/2609.20626","url_pdf":"https://arxiv.org/pdf/2609.20626v1","authors":"[\"Yu-Sen Zhou\",\"Wen-Tao Fu\",\"Li-Ming Cao\",\"Rong-Gen Cai\"]","published":"2026-09-17T16:12:29Z","proceeding":"gr-qc","tasks":"[\"gr-qc\",\"hep-th\"]","methods":"[]","has_code":false}