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Conserved quantities and integrability for massless spinning particles in general relativity
Phys. Rev. D 113, 064061 – Published 31 March, 2026
DOI: https://doi.org/10.1103/85dv-n8tr
Abstract
In general relativity, the dynamics of spinning particles is governed by the Mathisson-Papapetrou-Dixon equations, which are most commonly applied to massive bodies, but the framework also works in the massless case. Such massless versions naturally arise, for example, in the description of energy centroids of high-frequency wave packets. In this work, we consider massless spinning particles in spacetimes with hidden symmetries and we derive the generalized conservation laws associated with conformal Killing-Yano tensors. We then show that the spin Hall equations, a particular case of the Mathisson-Papapetrou-Dixon equations restricted to massless particles with longitudinal angular momentum, are completely integrable in a large class of type D spacetimes. Additionally, we also show that for massive spinning particles, the generalized Carter constant associated with Killing-Yano tensors is conserved independently of the choice of spin supplementary condition.
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References (112)
- M. Mathisson, Republication of: New mechanics of material systems, Gen. Relativ. Gravit. 42, 1011 (2010).
- A. Papapetrou, Spinning test-particles in general relativity. I, Proc. R. Soc. A 209, 248 (1951).
- W. G. Dixon, Dynamics of extended bodies in general relativity. I. Momentum and angular momentum, Proc. R. Soc. A 314, 499 (1970).
- W. G. Dixon, Dynamics of extended bodies in general relativity—II. Moments of the charge-current vector, Proc. R. Soc. A 319, 509 (1970).
- W. G. Dixon, Dynamics of extended bodies in general relativity. III. Equations of motion, Phil. Trans. R. Soc. A 277, 59 (1974).
- A. I. Harte, Mechanics of extended masses in general relativity, Classical Quantum Gravity 29, 055012 (2012).
- G. A. Piovano, C. Pantelidou, J. Mac Uilliam, and V. Witzany, Spinning particles near Kerr black holes: Orbits and gravitational-wave fluxes through the Hamilton-Jacobi formalism, Phys. Rev. D 111, 044009 (2025).
- J. Mathews, A. Pound, and B. Wardell, Self-force calculations with a spinning secondary, Phys. Rev. D 105, 084031 (2022).
- LISA Consortium Waveform Working Group, Waveform modelling for the Laser Interferometer Space Antenna, Living Rev. Relativity 28, 9 (2025).
- A. Pound and B. Wardell, Black hole perturbation theory and gravitational self-force, in Handbook of Gravitational Wave Astronomy, edited by C. Bambi, S. Katsanevas, and K. D. Kokkotas (Springer Nature, Singapore, 2022), pp. 1411–1529, 10.1007/978-981-16-4306-4_38.
- R. Rüdiger, The Dirac equation and spinning particles in general relativity, Proc. R. Soc. A 377, 417 (1981).
- J. Audretsch, Trajectories and spin motion of massive spin- particles in gravitational fields, J. Phys. A 14, 411 (1981).
- A. I. Harte and M. A. Oancea, Spin Hall effects and the localization of massless spinning particles, Phys. Rev. D 105, 104061 (2022).
- L. Andersson and M. A. Oancea, Spin Hall effects in the sky, Classical Quantum Gravity 40, 154002 (2023).
- J.-M. Souriau, Modèle de particule à spin dans le champ électromagnétique et gravitationnel, Ann. l’Inst. Henri Poincaré A 20, 315 (1974), http://www.numdam.org/item/AIHPA_1974__20_4_315_0/.
- P. Saturnini, Un modèle de particule à spin de masse nulle dans le champ de gravitation, Ph.D. thesis, Université de Provence, 1976, https://hal.archives-ouvertes.fr/tel-01344863.
- B. Mashhoon, Massless spinning test particles in a gravitational field, Ann. Phys. (N.Y.) 89, 254 (1975).
- M. Bailyn and S. Ragusa, Pole-dipole model of massless particles, Phys. Rev. D 15, 3543 (1977).
- M. Bailyn and S. Ragusa, Pole-dipole model of massless particles. II, Phys. Rev. D 23, 1258 (1981).
- D. Bini, C. Cherubini, A. Geralico, and R. T. Jantzen, Massless spinning test particles in algebraically special vacuum space–times, Int. J. Mod. Phys. D 15, 737 (2006).
- O. Semerák, Spinning particles in vacuum spacetimes of different curvature types: Natural reference tetrads and massless particles, Phys. Rev. D 92, 124036 (2015).
- C. Duval, Z. Horváth, and P. A. Horváthy, Fermat principle for spinning light, Phys. Rev. D 74, 021701 (2006).
- M. A. Oancea, J. Joudioux, I. Y. Dodin, D. E. Ruiz, C. F. Paganini, and L. Andersson, Gravitational spin Hall effect of light, Phys. Rev. D 102, 024075 (2020).
- M. A. Oancea and T. Harko, Weyl geometric effects on the propagation of light in gravitational fields, Phys. Rev. D 109, 064020 (2024).
- V. P. Frolov, Maxwell equations in a curved spacetime: Spin optics approximation, Phys. Rev. D 102, 084013 (2020).
- V. P. Frolov, Spinoptics in a curved spacetime, Phys. Rev. D 110, 064020 (2024).
- P. Gosselin, A. Bérard, and H. Mohrbach, Spin Hall effect of photons in a static gravitational field, Phys. Rev. D 75, 084035 (2007).
- L. Andersson, J. Joudioux, M. A. Oancea, and A. Raj, Propagation of polarized gravitational waves, Phys. Rev. D 103, 044053 (2021).
- N. Yamamoto, Spin Hall effect of gravitational waves, Phys. Rev. D 98, 061701(R) (2018).
- M. A. Oancea, R. Stiskalek, and M. Zumalacárregui, Frequency- and polarization-dependent lensing of gravitational waves in strong gravitational fields, Phys. Rev. D 109, 124045 (2024).
- M. A. Oancea, R. Stiskalek, and M. Zumalacárregui, Probing general relativistic spin–orbit coupling with gravitational waves from hierarchical triple systems, Mon. Not. R. Astron. Soc. 535, L1 (2024).
- V. P. Frolov and A. A. Shoom, Gravitational spinoptics in a curved space-time, J. Cosmol. Astropart. Phys. 10 (2024) 039.
- M. A. Oancea and A. Kumar, Semiclassical analysis of Dirac fields on curved spacetime, Phys. Rev. D 107, 044029 (2023).
- J. Sinova, S. O. Valenzuela, J. Wunderlich, C. H. Back, and T. Jungwirth, Spin Hall effects, Rev. Mod. Phys. 87, 1213 (2015).
- A. A. Bakun, B. P. Zakharchenya, A. A. Rogachev, M. N. Tkachuk, and V. G. Fleǐsher, Observation of a surface photocurrent caused by optical orientation of electrons in a semiconductor, Sov. J. Exp. Theor. Phys. Lett. 40, 1293 (1984), http://jetpletters.ru/ps/1262/article_19087.shtml.
- Y. K. Kato, R. C. Myers, A. C. Gossard, and D. D. Awschalom, Observation of the spin Hall effect in semiconductors, Science 306, 1910 (2004).
- K. Y. Bliokh, F. J. Rodríguez-Fortuño, F. Nori, and A. V. Zayats, Spin-orbit interactions of light, Nat. Photonics 9, 796 (2015).
- O. Hosten and P. Kwiat, Observation of the spin Hall effect of light via weak measurements, Science 319, 787 (2008).
- K. Y. Bliokh, A. Niv, V. Kleiner, and E. Hasman, Geometrodynamics of spinning light, Nat. Photonics 2, 748 (2008).
- V. P. Frolov, P. Krtouš, and D. Kubizňák, Black holes, hidden symmetries, and complete integrability, Living Rev. Relativity 20, 6 (2017).
- K. Yano, Some remarks on tensor fields and curvature, Ann. Math. 55, 328 (1952).
- S. Bochner, Curvature and Betti numbers, Ann. Math. 49, 379 (1948).
- B. Carter, Hamilton-Jacobi and Schrodinger separable solutions of Einstein’s equations, Commun. Math. Phys. 10, 280 (1968).
- B. Carter, Global structure of the Kerr family of gravitational fields, Phys. Rev. 174, 1559 (1968).
- S. A. Teukolsky, Rotating black holes: Separable wave equations for gravitational and electromagnetic perturbations, Phys. Rev. Lett. 29, 1114 (1972).
- L. Andersson, T. Bäckdahl, and P. Blue, Spin geometry and conservation laws in the Kerr spacetime, Surv. Diff. Geom. 20, 183 (2015).
- L. Andersson, T. Bäckdahl, and P. Blue, Second order symmetry operators, Classical Quantum Gravity 31, 135015 (2014).
- M. Walker and R. Penrose, On quadratic first integrals of the geodesic equations for type spacetimes, Commun. Math. Phys. 18, 265 (1970).
- R. Penrose and W. Rindler, Spinors and Space-Time (Cambridge University Press, Cambridge, England, 1988), Vol. 2, 10.1017/CBO9780511524486.
- B. Araneda, Symmetry operators and decoupled equations for linear fields on black hole spacetimes, Classical Quantum Gravity 34, 035002 (2017).
- B. Araneda, Conformal invariance, complex structures and the Teukolsky connection, Classical Quantum Gravity 35, 175001 (2018).
- S. Aksteiner, L. Andersson, B. Araneda, and B. Whiting, On the geometry of Petrov type II spacetimes, Classical Quantum Gravity 38, 135023 (2021).
- R. Rüdiger, Conserved quantities of spinning test particles in general relativity. I, Proc. R. Soc. A 375, 185 (1981).
- R. Rüdiger, Conserved quantities of spinning test particles in general relativity. II, Proc. R. Soc. A 385, 229 (1983).
- G. W. Gibbons, R. H. Rietdijk, and J. W. van Holten, SUSY in the sky, Nucl. Phys. B404, 42 (1993).
- G. Compère and A. Druart, Complete set of quasi-conserved quantities for spinning particles around Kerr, SciPost Phys. 12, 012 (2022).
- G. Compère, A. Druart, and J. Vines, Generalized Carter constant for quadrupolar test bodies in Kerr spacetime, SciPost Phys. 15, 226 (2023).
- V. Witzany, Hamilton-Jacobi equation for spinning particles near black holes, Phys. Rev. D 100, 104030 (2019).
- A. I. Harte, Approximate spacetime symmetries and conservation laws, Classical Quantum Gravity 25, 205008 (2008).
- P. Ramond, On the integrability of extended test body dynamics around black holes, Classical Quantum Gravity 42, 065019 (2025).
- V. Skoupý and V. Witzany, Analytic solution for the motion of spinning particles in Kerr spacetime, Phys. Rev. Lett. 134, 171401 (2025).
- S. Tanay, L. C. Stein, and J. T. Gálvez Ghersi, Integrability of eccentric, spinning black hole binaries up to second post-Newtonian order, Phys. Rev. D 103, 064066 (2021).
- A. Fasano and S. Marmi, Analytical Mechanics: An Introduction (OUP, Oxford, 2006), 10.1093/oso/9780198508021.001.0001.
- C. Duval and T. Schücker, Gravitational birefringence of light in Robertson-Walker cosmologies, Phys. Rev. D 96, 043517 (2017).
- A. I. Harte, T. B. Mieling, M. A. Oancea, and E. Steininger, Gravitational wave memory and its effects on particles and fields, Phys. Rev. D 111, 024034 (2025).
- V. P. Frolov, Spinoptics in the Schwarzschild spacetime, J. Cosmol. Astropart. Phys. 12 (2024) 051.
- V. P. Frolov and A. Koek, Spinoptics in the Kerr spacetime: Polarized wave scattering, Phys. Rev. D 111, 104081 (2025).
- S. Murk, D. R. Terno, and R. Vadapalli, Gravity-induced birefringence in spherically symmetric spacetimes, Phys. Rev. D 111, 044001 (2025).
- W. Sarlet, P. Leach, and F. Cantrijn, First integrals versus configurational invariants and a weak form of complete integrability, Physica D 17D, 87 (1985).
- J. F. Plebański and M. Demiański, Rotating, charged, and uniformly accelerating mass in general relativity, Ann. Phys. (N.Y.) 98, 98 (1976).
- H. Ovcharenko and J. Podolský, New class of rotating charged black holes with nonaligned electromagnetic field, Phys. Rev. D 112, 064076 (2025).
- W. G. Dixon, The new mechanics of Myron Mathisson and its subsequent development, in Equations of Motion in Relativistic Gravity, Fundamental Theories of Physics Vol. 179, edited by D. Puetzfeld, C. Lämmerzahl, and B. Schutz (Springer, Cham, 2015), pp. 1–66, 10.1007/978-3-319-18335-0_1.
- A. I. Harte, Motion in classical field theories and the foundations of the self-force problem, in Equations of Motion in Relativistic Gravity, Fundamental Theories of Physics Vol. 179, edited by D. Puetzfeld, C. Lämmerzahl, and B. Schutz (Springer, Cham, 2015), pp. 327–398, 10.1007/978-3-319-18335-0_12.
- L. F. O. Costa and J. Natário, Center of mass, spin supplementary conditions, and the momentum of spinning particles, in Equations of Motion in Relativistic Gravity, Fundamental Theories of Physics Vol. 179, edited by D. Puetzfeld, C. Lämmerzahl, and B. Schutz (Springer, Cham, 2015), pp. 215–258, 10.1007/978-3-319-18335-0_6.
- L. F. Costa, C. Herdeiro, J. Natário, and M. Zilhão, Mathisson’s helical motions for a spinning particle: Are they unphysical?, Phys. Rev. D 85, 024001 (2012).
- W. Tulczyjew, Motion of multipole particles in general relativity theory, Acta Phys. Pol. 18, 94 (1959), https://www.actaphys.uj.edu.pl/fulltext?series=T&vol=18&no=1&page=37.
- W. G. Dixon, A covariant multipole formalism for extended test bodies in general relativity, Nuovo Cimento (1955–1965) 34, 317 (1964).
- J. Ehlers and E. Rudolph, Dynamics of extended bodies in general relativity center-of-mass description and quasirigidity, Gen. Relativ. Gravit. 8, 197 (1977).
- J. Vines, D. Kunst, J. Steinhoff, and T. Hinderer, Canonical Hamiltonian for an extended test body in curved spacetime: To quadratic order in spin, Phys. Rev. D 93, 103008 (2016).
- K. Y. Bliokh and F. Nori, Transverse and longitudinal angular momenta of light, Phys. Rep. 592, 1 (2015).
- T. Houri, T. Oota, and Y. Yasui, Closed conformal Killing-Yano tensor and Kerr-NUT-de Sitter spacetime uniqueness, Phys. Lett. B 656, 214 (2007).
- J. J. Ferrando and J. A. Saez, An Intrinsic characterization of the Kerr metric, Classical Quantum Gravity 26, 075013 (2009).
- P. Krtous, V. P. Frolov, and D. Kubiznak, Hidden symmetries of higher dimensional black holes and uniqueness of the Kerr-NUT-(A)dS spacetime, Phys. Rev. D 78, 064022 (2008).
- R. M. Wald, General Relativity (University of Chicago Press, Chicago, 1984), 10.7208/chicago/9780226870373.001.0001.
- C. Batista, Integrability conditions for Killing-Yano tensors and conformal Killing-Yano tensors, Phys. Rev. D 91, 024013 (2015).
- S.-i. Tachibana and T. Kashiwada, On the integrability of Killing-Yano’s equation, J. Math. Soc. Jpn. 21, 259 (1969).
- T. Houri, K. Tomoda, and Y. Yasui, On integrability of the Killing equation, Classical Quantum Gravity 35, 075014 (2018).
- T. Houri and Y. Yasui, A simple test for spacetime symmetry, Classical Quantum Gravity 32, 055002 (2015).
- R. P. Kerr, Gravitational field of a spinning mass as an example of algebraically special metrics, Phys. Rev. Lett. 11, 237 (1963).
- J. Jezierski and M. Łukasik, Conformal Yano–Killing tensor for the Kerr metric and conserved quantities, Classical Quantum Gravity 23, 2895 (2006).
- E. Newman, L. Tamburino, and T. Unti, Empty space generalization of the Schwarzschild metric, J. Math. Phys. (N.Y.) 4, 915 (1963).
- L. P. Hughston and P. Sommers, The symmetries of Kerr black holes, Commun. Math. Phys. 33, 129 (1973).
- J. B. Griffiths and J. Podolský, A new look at the Plebański-Demiański family of solutions, Int. J. Mod. Phys. D 15, 335 (2006).
- H. Ovcharenko, J. Podolský, and M. Astorino, Black holes of type D revisited: Relating their various metric forms, Phys. Rev. D 111, 024038 (2025).
- H. Ovcharenko, J. Podolský, and M. Astorino, Revisiting black holes of algebraic type D with a cosmological constant, Phys. Rev. D 111, 084016 (2025).
- D. Kubizňák and P. Krtouš, Conformal Killing-Yano tensors for the Plebański–Demiański family of solutions, Phys. Rev. D 76, 084036 (2007).
- J. Podolský and H. Ovcharenko, Kerr black hole in a uniform Bertotti-Robinson magnetic field: An exact solution, Phys. Rev. Lett. 135, 181401 (2025).
- F. Gray, D. Kubiznak, H. Ovcharenko, and J. Podolský, Hidden symmetries and separability structures of Ovcharenko-Podolský and conformal-to-Carter spacetimes, Phys. Rev. D 113, 044050 (2026).
- F. Gray and D. Kubizňák, Homogeneous symmetry operators in Kerr-NUT-AdS spacetimes, Phys. Rev. D 109, 084027 (2024).
- J. M. Martín-García, xAct: Efficient tensor computer algebra for the Wolfram Language (2025), https://www.xact.es/.
- Wolfram Research, Inc., Mathematica, Version 13.1 (2021), Champaign, US-IL, https://www.wolfram.com/mathematica.
- See Supplemental Material at http://link.aps.org/supplemental/10.1103/85dv-n8tr for the Mathematica notebook where these calculations are implemented.
- J. Liouville, Note sur l’intégration des équations différentielles de la Dynamique, présentée au Bureau des Longitudes le 29 juin 1853, J. Math. Pures Appl. 1 20, 137 (1855), https://www.numdam.org/item/JMPA_1855_1_20__137_0/.
- V. I. Arnol’d, V. V. Kozlov, A. I. Neishtadt, and I. Iacob, Mathematical Aspects of Classical and Celestial Mechanics (Springer, New York, 2006), Vol. 3, 10.1007/978-3-540-48926-9.
- T. Hinderer and E. E. Flanagan, Two-timescale analysis of extreme mass ratio inspirals in Kerr spacetime: Orbital motion, Phys. Rev. D 78, 064028 (2008).
- A. M. Escobar-Ruiz and R. Azuaje, On particular integrability in classical mechanics, J. Phys. A 57, 105202 (2024).
- V. A. Sharafutdinov, Integral Geometry of Tensor Fields, Inverse and Ill-Posed Problems Series (VSP, Utrecht, 1994), 10.1515/9783110900095.
- L. Andersson, B. Moser, M. A. Oancea, C. F. Paganini, and G. Schmid, Pseudodifferential Weyl calculus on vector bundles, arXiv:2507.11965.
- M. A. Oancea, Spin Hall effects in general relativity, Ph.D. thesis, University of Potsdam, 2021, 10.25932/publishup-50229.
- P. Krtous, D. Kubiznak, D. N. Page, and M. Vasudevan, Constants of geodesic motion in higher-dimensional black-hole spacetimes, Phys. Rev. D 76, 084034 (2007).
- A. I. Harte and D. Dwyer, Local symmetries as constraints on the motion of freely falling extended bodies, Phys. Rev. D 108, 124005 (2023).
- K.-i. Kubota, S. Arai, H. Motohashi, and S. Mukohyama, Spin wave optics for gravitational waves lensed by a Kerr black hole, Phys. Rev. D 110, 124011 (2024).