Dr Juan Valiente-KroonReader in Applied Mathematics, Director of ResearchEmail: j.a.valiente-kroon@qmul.ac.ukTelephone: +44 (0)20 7882 5493Room Number: Mathematical Sciences Building, Room: MB-421Website: http://www.maths.qmul.ac.uk/~jav/Site/Welcome.htmlOffice Hours: Thursdays: 13:00-14:00 (including SEFP advisees) Alternatively, by appointment via emailProfileResearchPublicationsProfile Dr Juan A. Valiente Kroon is a Reader in Applied Mathematics and Head of the Geometry and Analysis group of the School of Mathematical Sciences. He obtained his PhD from the University of London in 2000 and was a postdoctoral researcher at the Max Planck Institute for Gravitational Physics (Albert Einstein Institute) and at the University of Vienna (Lise Meitner fellow). He joined QMUL as an EPSRC Advanced Research fellow. He carries out research on mathematical aspects of General Relativity with a particular focus on the use of conformal and spinorial methods to analyse the global properties of solutions to the Einstein field equations. He is also interested in the use of computer algebra and numerical methods to study the equations of General Relativity. Dr. Valiente Kroon is the author of over 50 research articles and of the book “Conformal Methods in General Relativity” in the prestigious series “Cambridge Monographs on Mathematical Physics”. He is currently the supervisor of five PhD students and teaches a third-year course on Partial Differential Equations and a postgraduate course on mathematical aspects of General Relativity at the London Mathematical Society. ResearchResearch Interests:Mathematical General Relativity.Publications Minucci M, Valiente Kroon JA (2023). On the non-linear stability of the Cosmological region of the Schwarzschild-de Sitter spacetime Classical and Quantum Gravity nameOfConference. 10.1088/1361-6382/acdb3f https://qmro.qmul.ac.uk/xmlui/handle/123456789/89871 Sansom R, Kroon JAV (2023). Dain’s invariant for black hole initial data Classical and Quantum Gravity nameOfConference. 10.1088/1361-6382/accccb https://qmro.qmul.ac.uk/xmlui/handle/123456789/86840 Kroon JAV (2023). Conformal Methods in General Relativity journal nameOfConference. 10.1017/9781009291309 qmroHref Kopiński J, Kroon JAV (2022). Bach equation and the matching of spacetimes in conformal cyclic cosmology models Physical Review D nameOfConference. 10.1103/physrevd.106.084034 https://qmro.qmul.ac.uk/xmlui/handle/123456789/82938 Minucci M, MacEdo RP, Valiente Kroon JA (2022). The Maxwell-scalar field system near spatial infinity Journal of Mathematical Physics nameOfConference. 10.1063/5.0104602 https://qmro.qmul.ac.uk/xmlui/handle/123456789/81700 Beheshti S, Normann M, Kroon JAV (2022). Future stability of self-gravitating dust balls in an expanding universe Physical Review D nameOfConference. 10.1103/physrevd.105.124027 https://qmro.qmul.ac.uk/xmlui/handle/123456789/79302 Magdy Ali Mohamed M, Valiente Kroon JA (2022). Asymptotic charges for spin-1 and spin-2 fields at the critical sets of null infinity Journal of Mathematical Physics nameOfConference. 10.1063/5.0081834 https://qmro.qmul.ac.uk/xmlui/handle/123456789/79002 Gasperín E, Kroon JAV (2021). Staticity and regularity for zero rest-mass fields near spatial infinity on flat spacetime Classical and Quantum Gravity nameOfConference. 10.1088/1361-6382/ac37ce https://qmro.qmul.ac.uk/xmlui/handle/123456789/75974 Zhao P, Hilditch D, Kroon JAV (2021). The conformal Einstein field equations and the local extension of future null infinity Journal of Mathematical Physics nameOfConference. 10.1063/5.0056969 https://qmro.qmul.ac.uk/xmlui/handle/123456789/74754 Ali Mohamed MM, Valiente Kroon JA (2021). A comparison of Ashtekar’s and Friedrich’s formalisms of spatial infinity Classical and Quantum Gravity nameOfConference. 10.1088/1361-6382/ac1208 https://qmro.qmul.ac.uk/xmlui/handle/123456789/73477 Minucci M, Valiente Kroon JA (2021). A conformal approach to the stability of Einstein spaces with spatial sections of negative scalar curvature Classical and Quantum Gravity nameOfConference. 10.1088/1361-6382/ac0356 https://qmro.qmul.ac.uk/xmlui/handle/123456789/72951 Joudioux J, Thaller M, Valiente Kroon JA (2021). The conformal Einstein field equations with massless Vlasov matter Annales de l’institut Fourier nameOfConference. 10.5802/aif.3414 https://qmro.qmul.ac.uk/xmlui/handle/123456789/73870 Kopiński J, Kroon JAV (2021). New spinorial approach to mass inequalities for black holes in general relativity Physical Review D nameOfConference. 10.1103/physrevd.103.024057 https://qmro.qmul.ac.uk/xmlui/handle/123456789/70409 Joudioux J, Thaller M, Kroon JAV (2021). THE CONFORMAL EINSTEIN FIELD EQUATIONS WITH MASSLESS VLASOV MATTER Annales de l'Institut Fourier nameOfConference. doi https://qmro.qmul.ac.uk/xmlui/handle/123456789/76442 Gasperín E, Valiente Kroon JA (2020). Zero rest-mass fields and the Newman–Penrose constants on flat space Journal of Mathematical Physics nameOfConference. 10.1063/5.0034784 https://qmro.qmul.ac.uk/xmlui/handle/123456789/70206 Normann M, Valiente Kroon JA (2020). Evolution equations for a wide range of Einstein-matter systems General Relativity and Gravitation nameOfConference. 10.1007/s10714-020-02759-y https://qmro.qmul.ac.uk/xmlui/handle/123456789/69039 Hilditch D, Valiente Kroon JA, Zhao P (2020). Revisiting the characteristic initial value problem for the vacuum Einstein field equations General Relativity and Gravitation nameOfConference. 10.1007/s10714-020-02747-2 https://qmro.qmul.ac.uk/xmlui/handle/123456789/67820 Hilditch D, Valiente Kroon JA, Zhao P (2020). Improved existence for the characteristic initial value problem with the conformal Einstein field equations General Relativity and Gravitation nameOfConference. 10.1007/s10714-020-02734-7 https://qmro.qmul.ac.uk/xmlui/handle/123456789/67199 Barausse E, Berti E, Hertog T et al. (2020). Prospects for fundamental physics with LISA General Relativity and Gravitation nameOfConference. 10.1007/s10714-020-02691-1 https://qmro.qmul.ac.uk/xmlui/handle/123456789/67068 Carranza DA, Valiente Kroon JA (2019). Construction of anti-de Sitter-like spacetimes using the metric conformal Einstein field equations: the tracefree matter case Classical and Quantum Gravity nameOfConference. 10.1088/1361-6382/ab47d8 https://qmro.qmul.ac.uk/xmlui/handle/123456789/61250 Carranza DA, Hursit AE, Valiente Kroon JA (2019). Conformal wave equations for the Einstein-tracefree matter system General Relativity and Gravitation nameOfConference. 10.1007/s10714-019-2567-5 https://qmro.qmul.ac.uk/xmlui/handle/123456789/58620 Valiente Kroon JA, Williams JL (2019). A perturbative approach to the construction of initial data on compact manifolds Pure and Applied Mathematics Quarterly nameOfConference. 10.4310/PAMQ.2019.v15.n3.a1 https://qmro.qmul.ac.uk/xmlui/handle/123456789/59699 Carranza DA, Kroon JAV (2018). Construction of anti-de Sitter-like spacetimes using the metric conformal Einstein field equations: the vacuum case CLASSICAL AND QUANTUM GRAVITY nameOfConference. 10.1088/1361-6382/aaeb54 https://qmro.qmul.ac.uk/xmlui/handle/123456789/54641 VALIENTE KROON JA, COLE MJ, Racz I (2018). Killing spinor data on distorted black hole horizons and the uniqueness of stationary vacuum black holes Classical and Quantum Gravity nameOfConference. 10.1088/1361-6382/aade6e https://qmro.qmul.ac.uk/xmlui/handle/123456789/45584 Carranza DA, Kroon JAV (2018). Killing boundary data for anti-de Sitter-like spacetimes CLASSICAL AND QUANTUM GRAVITY nameOfConference. 10.1088/1361-6382/aacdd2 https://qmro.qmul.ac.uk/xmlui/handle/123456789/43483 Macedo RP, Kroon JAV (2018). Spectral methods for the spin-2 equation near the cylinder at spatial infinity CLASSICAL AND QUANTUM GRAVITY nameOfConference. 10.1088/1361-6382/aac116 https://qmro.qmul.ac.uk/xmlui/handle/123456789/39585 Garcia-Parrado Gomez-Lobo A, Gasperin E, Valiente Kroon JA (2018). Conformal geodesics in spherically symmetric vacuum spacetimes with cosmological constant CLASSICAL AND QUANTUM GRAVITY nameOfConference. 10.1088/1361-6382/aa9f59 https://qmro.qmul.ac.uk/xmlui/handle/123456789/32420 VALIENTE KROON JA, Alho A, Mena FC (2017). The Einstein-Friedrich-nonlinear scalar field system and the stability of scalar field cosmologies Advances in Theoretical and Mathematical Physics nameOfConference. 10.4310/ATMP.2017.v21.n4.a1 https://qmro.qmul.ac.uk/xmlui/handle/123456789/27823 Gasperin E, Valiente Kroon JA (2017). Polyhomogeneous expansions from time symmetric initial data Classical and Quantum Gravity nameOfConference. 10.1088/1361-6382/aa87bf https://qmro.qmul.ac.uk/xmlui/handle/123456789/54224 VALIENTE KROON JA (2017). A Geometric Invariant Characterising Initial Data for the Kerr–Newman Spacetime Annales Henri Poincaré nameOfConference. 10.1007/s00023-017-0606-x https://qmro.qmul.ac.uk/xmlui/handle/123456789/25417 Kroon JAV, Williams JL (2017). Dain's invariant on non-time symmetric initial data sets CLASSICAL AND QUANTUM GRAVITY nameOfConference. 10.1088/1361-6382/aa7102 https://qmro.qmul.ac.uk/xmlui/handle/123456789/53685 VALIENTE KROON JA (2017). Perturbations of the asymptotic region of the Schwarzschild-de Sitter spacetime Annales Henri Poincare nameOfConference. 10.1007/s00023-016-0544-z https://qmro.qmul.ac.uk/xmlui/handle/123456789/18485 Valiente Kroon JA (2017). Mathematical Problems of General Relativity journal nameOfConference. 10.1142/9781786341006_0006 qmroHref Kroon JAV (2016). Conformal Methods in General Relativity journal nameOfConference. 10.1017/cbo9781139523950 qmroHref Cole MJ, Kroon JAV (2016). Killing spinors as a characterisation of rotating black hole spacetimes Classical and Quantum Gravity nameOfConference. 10.1088/0264-9381/33/12/125019 https://qmro.qmul.ac.uk/xmlui/handle/123456789/13389 Pugliese D, Kroon JAV (2016). On the locally rotationally symmetric Einstein-Maxwell perfect fluid General Relativity and Gravitation nameOfConference. 10.1007/s10714-016-2068-8 https://qmro.qmul.ac.uk/xmlui/handle/123456789/13143 Bäckdahl T, Valiente Kroon JA (2016). A formalism for the calculus of variations with spinors Journal of Mathematical Physics nameOfConference. 10.1063/1.4939562 https://qmro.qmul.ac.uk/xmlui/handle/123456789/14880 Gasperín E, Kroon JAV (2015). Spinorial wave equations and stability of the Milne spacetime Classical and Quantum Gravity nameOfConference. 10.1088/0264-9381/32/18/185021 https://qmro.qmul.ac.uk/xmlui/handle/123456789/19010 McManus TM, Valiente-Kroon JA, Horsley SAR et al. (2014). Illusions and cloaks for surface waves. Sci Rep nameOfConference. 10.1038/srep05977 https://qmro.qmul.ac.uk/xmlui/handle/123456789/13154 Kroon JAV, Lübbe C (2014). A Class of Conformal Curves on Spherically Symmetric Spacetimes journal nameOfConference. 10.1007/978-3-319-06761-2_30 qmroHref Bäckdahl T, Valiente Kroon JA (2014). How to Measure Deviation from the Kerr Initial Data: Recent Progress journal nameOfConference. 10.1007/978-3-319-06761-2_3 qmroHref Lübbe C, Valiente Kroon JA (2014). The Conformal Einstein Field Equations for Trace-free Perfect Fluids journal nameOfConference. 10.1007/978-3-319-06761-2_17 qmroHref Luebbe C, Kroon JAV (2014). A Class of Conformal Curves in the Reissner-Nordstrom Spacetime ANNALES HENRI POINCARE nameOfConference. 10.1007/s00023-013-0276-2 qmroHref Luebbe C, Kroon JAV (2014). On the conformal structure of the extremal Reissner-Nordstrom spacetime CLASSICAL AND QUANTUM GRAVITY nameOfConference. 10.1088/0264-9381/31/17/175015 https://qmro.qmul.ac.uk/xmlui/handle/123456789/19011 Luebbe C, Kroon JAV (2014). Spherically symmetric anti-de Sitter-like Einstein-Yang-Mills spacetimes PHYSICAL REVIEW D nameOfConference. 10.1103/PhysRevD.90.024021 qmroHref Luebbe C, Kroon J-AV (2013). A conformal approach for the analysis of the non-linear stability of radiation cosmologies ANNALS OF PHYSICS nameOfConference. 10.1016/j.aop.2012.10.011 qmroHref Pugliese D, Kroon JAV (2013). On the evolution equations for a self-gravitating charged scalar field GENERAL RELATIVITY AND GRAVITATION nameOfConference. 10.1007/s10714-013-1524-y qmroHref KROON JAV (2006). A NEW CLASS OF OBSTRUCTIONS TO THE SMOOTHNESS OF NULL INFINITY journal The Tenth Marcel Grossmann Meeting. 10.1142/9789812704030_0216 qmroHref LAZKOZ R, KROON JAV (2006). THE NEWTONIAN LIMIT OF THE SPACETIMES DESCRIBING UNIFORMLY ACCELERATED PARTICLES journal The Tenth Marcel Grossmann Meeting. 10.1142/9789812704030_0245 qmroHref VALIENTE KROON JA (2006). THE SMOOTHNESS OF NULL INFINITY: ITS RELEVANCE FOR NUMERICAL RELATIVITY journal The Tenth Marcel Grossmann Meeting. 10.1142/9789812704030_0162 qmroHref Kroon JAV (2012). Asymptotic Simplicity and Static Data ANNALES HENRI POINCARE nameOfConference. 10.1007/s00023-011-0122-3 qmroHref Baeckdahl T, Kroon JAV (2012). Constructing "non-Kerrness" on compact domains JOURNAL OF MATHEMATICAL PHYSICS nameOfConference. 10.1063/1.3702569 qmroHref Pugliese D, Kroon JAV (2012). On the evolution equations for ideal magnetohydrodynamics in curved spacetime GENERAL RELATIVITY AND GRAVITATION nameOfConference. 10.1007/s10714-012-1424-6 qmroHref Luebbe C, Kroon JAV (2012). The extended conformal Einstein field equations with matter: The Einstein-Maxwell field JOURNAL OF GEOMETRY AND PHYSICS nameOfConference. 10.1016/j.geomphys.2012.01.009 qmroHref LAZKOZ SAEZ R, VALIENTE KROON JA (2001). ON RADIATIVE PROPERTIES OF BOOST-ROTATION SYMMETRIC, TYPE D SPACETIMES journal Reference Frames and Gravitomagnetism. 10.1142/9789812810021_0034 qmroHref Backdahl T, Kroon JAV (2011). The 'non-Kerrness' of domains of outer communication of black holes and exteriors of stars P ROY SOC A-MATH PHY nameOfConference. 10.1098/rspa.2010.0535 qmroHref Backdahl T, Kroon JAV (2011). Approximate twistors and positive mass CLASSICAL QUANT GRAV nameOfConference. 10.1088/0264-9381/28/7/075010 qmroHref Acena AE, Kroon JAV (2011). Conformal extensions for stationary spacetimes CLASSICAL AND QUANTUM GRAVITY nameOfConference. 10.1088/0264-9381/28/22/225023 qmroHref Kroon JAV (2011). Geometric invariants for initial data sets: analysis, exact solutions, computer algebra, numerics SPANISH RELATIVITY MEETING (ERE 2010): GRAVITY AS A CROSSROAD IN PHYSICS nameOfConference. 10.1088/1742-6596/314/1/012016 qmroHref Alho A, Mena FC, Kroon JAV (2011). On the non-linear stability of scalar field cosmologies SPANISH RELATIVITY MEETING (ERE 2010): GRAVITY AS A CROSSROAD IN PHYSICS nameOfConference. 10.1088/1742-6596/314/1/012099 qmroHref Backdahl T, Kroon JAV (2010). On the Construction of a Geometric Invariant Measuring the Deviation from Kerr Data ANN HENRI POINCARE nameOfConference. 10.1007/s00023-010-0063-2 qmroHref Kroon JAV (2010). A Rigidity Property of Asymptotically Simple Spacetimes Arising from Conformally Flat Data COMMUN MATH PHYS nameOfConference. 10.1007/s00220-010-1002-2 qmroHref Lubbe C, Kroon JAV (2010). A STABILITY RESULT FOR PURELY RADIATIVE SPACETIMES J HYPERBOL DIFFER EQ nameOfConference. 10.1142/S0219891610002220 qmroHref Backdahl T, Kroon JAV (2010). Geometric Invariant Measuring the Deviation from Kerr Data PHYS REV LETT nameOfConference. 10.1103/PhysRevLett.104.231102 qmroHref Kroon JAV (2009). Regularity Conditions for Einstein's Equations at Spatial Infinity ANN HENRI POINCARE nameOfConference. 10.1007/s00023-009-0424-x qmroHref Lübbe C, Kroon JAV (2009). On de Sitter-like and Minkowski-like spacetimes Classical and Quantum Gravity nameOfConference. 10.1088/0264-9381/26/14/145012 qmroHref Kroon JAV (2009). ESTIMATES FOR THE MAXWELL FIELD NEAR THE SPATIAL AND NULL INFINITY OF THE SCHWARZSCHILD SPACETIME J HYPERBOL DIFFER EQ nameOfConference. 10.1142/s0219891609001861 qmroHref Gomez-Lobo AGP, Kroon JAV (2009). Kerr initial data PHYSICS AND MATHEMATICS OF GRAVITATION nameOfConference. 10.1063/1.3141291 qmroHref Gomez-Lobo AGP, Kroon JAV (2008). Kerr initial data CLASSICAL QUANT GRAV nameOfConference. 10.1088/0264-9381/25/20/205018 qmroHref Gomez-Lobo AGP, Kroon JAV (2008). Killing spinor initial data sets J GEOM PHYS nameOfConference. 10.1016/j.geomphys.2008.04.003 qmroHref Jaramillo JL, Kroon JAV, Gourgoulhon E (2008). From geometry to numerics: interdisciplinary aspects in mathematical and numerical relativity CLASSICAL QUANT GRAV nameOfConference. 10.1088/0264-9381/25/9/093001 qmroHref Antonio J, Kroon V (2007). The Maxwell field on the Schwarzschild space-time: behaviour near spatial infinity P R SOC A nameOfConference. 10.1098/rspa.2007.1896 qmroHref Kroon JAV (2007). Asymptotic properties of the development of conformally flat data near spatial infinity CLASSICAL QUANT GRAV nameOfConference. 10.1088/0264-9381/24/11/016 qmroHref Gomez-Lobo AGP, Kroon JAV (2007). Initial data sets for the Schwarzschild spacetime PHYS REV D nameOfConference. 10.1103/PhysRevD.75.024027 qmroHref Kroon JAV (2006). On smoothness-asymmetric null infinities CLASSICAL QUANT GRAV nameOfConference. 10.1088/0264-9381/223/10/022 qmroHref Kroon JAV (2005). Characterization of Schwarzschildean initial data PHYS REV D nameOfConference. 10.1103/PhysRevD.72.084003 qmroHref Kroon JAV (2005). Time asymmetric spacetimes near null and spatial infinity: II. Expansions of developments of initial data sets with non-smooth conformal metrics CLASSICAL QUANT GRAV nameOfConference. 10.1088/0264-9381/22/9/015 qmroHref Kroon JAV (2004). Time asymmetric spacetimes near null and spatial infinity: I. Expansions of developments of conformally flat data CLASSICAL QUANT GRAV nameOfConference. 10.1088/0264-9381/21/23/011 qmroHref Kroon JAV (2004). Does asymptotic simplicity allow for radiation near spatial infinity? COMMUN MATH PHYS nameOfConference. 10.1007/s00220-004-1174-8 qmroHref Kroon JAV (2004). Asymptotic expansions of the Cotton-York tensor on slices of stationary spacetimes CLASSICAL QUANT GRAV nameOfConference. 10.1088/0264-9381/21/13/009 qmroHref Lazkoz R, Kroon JAV (2004). The Newtonian limit of space-times describing uniformly accelerated particles P ROY SOC LOND A MAT nameOfConference. 10.1098/rspa.2003.1172 qmroHref Kroon JAV (2004). Nonexistence of conformally flat slices in Kerr and other stationary spacetimes PHYS REV LETT nameOfConference. 10.1103/PhysRevLett.92.041101 qmroHref Kroon JAV (2004). A new class of obstructions to the smoothness of null infinity COMMUN MATH PHYS nameOfConference. 10.1007/s00220-003-0967-5 qmroHref Lazkoz R, Kroon JAV (2003). Gravitational waves REV MEX FIS nameOfConference. doi qmroHref Kroon JAV (2003). Early radiative properties of the developments of time-symmetric conformally flat initial data CLASSICAL QUANT GRAV nameOfConference. 10.1088/0264-9381/20/5/102 qmroHref Dain S, Valiente-Kroon JA (2002). Conserved quantities in a black hole collision CLASSICAL QUANT GRAV nameOfConference. 10.1088/0264-9381/19/4/312 qmroHref Kroon JAV (2002). Polyhomogeneous expansions close to null and spatial infinity CONFORMAL STRUCTURE OF SPACE-TIME: GEOMETRY, ANALYSIS, NUMERICS nameOfConference. 10.1007/3-540-45818-2_7 qmroHref Kroon JAV (2001). Can one detect a non-smooth null infinity? CLASSICAL QUANT GRAV nameOfConference. 10.1088/0264-9381/18/20/310 qmroHref