https://hackerpaper.kaipfister.de/p/1010.5260/Collected HN comments and submissions linking this paper.enMon, 02 Nov 2026 11:16:22 GMThttps://news.ycombinator.com/item?id=34968968urn:hackerpapers:mention:1010.5260:34968968Tue, 28 Feb 2023 13:22:20 GMT<p>In a Kerr black hole spacetime there is no orbital angular momentum (OAM, L), only the intrinsic spin angular momentum (SAM, S). One can get OAM in a relativistic n-body black hole problem. Each of those black holes will have its own SAM. See §5.11. ANGULAR MOMENTUM in Misner, Thorne &amp; Wheeler (MTW) and in particular Box 5.6 D (Intrinsic Angular Momentum) and E (Decomposition of Angular Momentum into Intrinsic and Orbital Parts). The latter gives J = L + S. Admittedly, in MTW §33 the authors prefer to use S (e.g. eqn. 33.4) but that raises the important caveat for binary black hole (BBH)…</p><p><a href="https://hackerpaper.kaipfister.de/p/1010.5260/">Paper and discussion history</a>. A mention is not an endorsement.</p>gr-qc