Ivan Booth
Current Organizations / Institutes
The organizations/institutes from the scholar's latest article
Previous Organizations / Institutes
The organizations / institutes from the scholar's other articles in the past ten years
Research Subjects
Research Interests
Ivan Booth has a total of 44 co-authors. Here are the top co-authors by number of shared publications:
- Hari K. Kunduri
Department of Mathematics and Statistics and Department of Physics and Astronomy, McMaster University, Hamilton, Canada
14 shared publications - Robie A. Hennigar
Durham University
10 shared publications - David Wenjie Tian
Faculty of Science Memorial University A1C 5S7 St. John's Newfoundland Canada
8 shared publications - Michal P. Heller
Ghent University
5 shared publications - Shohreh Abdolrahimi
California State Polytechnic University
4 shared publications - Uzair Hussain
Department of Mathematics and Statistics Memorial University of Newfoundland St John's NL A1C 4P5 Canada
4 shared publications
Latest Publications
- 23 February 2026
- Published by American Physical Society (APS) in Physical Review D
- Vol. 113 (4)
Distorted black ring with rotation on the two-sphere
- 23 February 2026
- Published by American Physical Society (APS) in Physical Review D
- Vol. 113 (4)
Distorted black ring with rotation on the two-sphere
- Open Access
Distorted black ring with rotation on the two-sphere
We construct a stationary black ring spacetime with rotation only along the $S^2$ direction that is free of conical singularities. We use a solution-generating technique to add external gravitational fields and show these can be used to remove conical singularities from an asymptotically flat black ring with a rotating $S^2$.Open AccessDistorted black ring with rotation on the two-sphere
We construct a stationary black ring spacetime with rotation only along the $S^2$ direction that is free of conical singularities. We use a solution-generating technique to add external gravitational fields and show these can be used to remove conical singularities from an asymptotically flat black ring with a rotating $S^2$. - 1 October 2024
- Published by American Association of Physics Teachers (AAPT) in American Journal of Physics
- Vol. 92 (10) , 743-751
What is a degree of freedom? Configuration spaces and their topology
Understanding degrees of freedom in classical mechanics is fundamental to characterizing physical systems. Counting them is usually easy, especially if we can assign them a clear meaning. However, the precise definition of a degree of freedom is not usually presented in first-year physics courses since it requires mathematical knowledge only learned in more advanced courses. In this paper, we use a pedagogical approach motivated by simple but non-trivial mechanical examples to define degrees of freedom and configuration spaces. We highlight the role that topology plays in understanding these ideas.
- 1 October 2024
- Published by American Association of Physics Teachers (AAPT) in American Journal of Physics
- Vol. 92 (10) , 743-751
What is a degree of freedom? Configuration spaces and their topology
Understanding degrees of freedom in classical mechanics is fundamental to characterizing physical systems. Counting them is usually easy, especially if we can assign them a clear meaning. However, the precise definition of a degree of freedom is not usually presented in first-year physics courses since it requires mathematical knowledge only learned in more advanced courses. In this paper, we use a pedagogical approach motivated by simple but non-trivial mechanical examples to define degrees of freedom and configuration spaces. We highlight the role that topology plays in understanding these ideas.
- 30 August 2024
- Published by American Physical Society (APS) in Physical Review D
- Vol. 110 (4) , 044071
Distorted static black holes with a bubble
We construct a family of local static, vacuum five-dimensional solutions with two commuting spatial isometries describing a black hole with a horizon and a 2-cycle “bubble” in the domain of outer communications. The solutions are obtained by adding distortions to an asymptotically flat seed solution. We show that the conical singularities in the undistorted geometry can be removed by an appropriate choice of the distortion.- 30 August 2024
- Published by American Physical Society (APS) in Physical Review D
- Vol. 110 (4) , 044071
Distorted static black holes with a bubble
We construct a family of local static, vacuum five-dimensional solutions with two commuting spatial isometries describing a black hole with a horizon and a 2-cycle “bubble” in the domain of outer communications. The solutions are obtained by adding distortions to an asymptotically flat seed solution. We show that the conical singularities in the undistorted geometry can be removed by an appropriate choice of the distortion.- 10 June 2024
- Published by American Physical Society (APS) in Physical Review D
- Vol. 109 (12) , 124023
Marginally outer trapped tori in black hole spacetimes
During a binary black hole merger, multiple intermediary marginally outer trapped tubes connect the initial pair of apparent horizons with the final (single) apparent horizon. The marginally outer trapped surfaces (MOTSs) that foliate these tubes can have complicated geometries as well as nonspherical topologies. In particular, toroidal MOTSs form inside both of the original black holes during the early stages of a head-on merger that starts from time-symmetric initial data [1]. We show that toroidal MOTSs also form in the maximal analytic extension of the Schwarzschild spacetime as Kruskal time advances from the moment of time symmetry. As for the merger simulations, they cross the Einstein-Rosen bridge and are tightly sandwiched between the apparent horizons in the two asymptotic regions at early times. This strongly suggests that their formation is a consequence of the initial conditions rather than merger physics. Finally, we consider MOTSs of spherical topology in the Kruskal-Szekeres slicing and study their properties. All of these are contained within the apparent horizon but some do not enclose the wormhole.- 10 June 2024
- Published by American Physical Society (APS) in Physical Review D
- Vol. 109 (12) , 124023
Marginally outer trapped tori in black hole spacetimes
During a binary black hole merger, multiple intermediary marginally outer trapped tubes connect the initial pair of apparent horizons with the final (single) apparent horizon. The marginally outer trapped surfaces (MOTSs) that foliate these tubes can have complicated geometries as well as nonspherical topologies. In particular, toroidal MOTSs form inside both of the original black holes during the early stages of a head-on merger that starts from time-symmetric initial data [1]. We show that toroidal MOTSs also form in the maximal analytic extension of the Schwarzschild spacetime as Kruskal time advances from the moment of time symmetry. As for the merger simulations, they cross the Einstein-Rosen bridge and are tightly sandwiched between the apparent horizons in the two asymptotic regions at early times. This strongly suggests that their formation is a consequence of the initial conditions rather than merger physics. Finally, we consider MOTSs of spherical topology in the Kruskal-Szekeres slicing and study their properties. All of these are contained within the apparent horizon but some do not enclose the wormhole.- Open Access
- 2 May 2024
- Published by IOP Publishing in Classical and Quantum Gravity
- Vol. 41 (11) , 115003
Symmetry and instability of marginally outer trapped surfaces
We consider an initial data set having a continuous symmetry and a marginally outer trapped surface (MOTS) that is not preserved by this symmetry. We show that such a MOTS is unstable except in an exceptional case. In non-rotating cases we provide a Courant-type lower bound on the number of unstable eigenvalues. These results are then used to prove the instability of a large class of exotic MOTSs that were recently observed in the Schwarzschild spacetime. We also discuss the implications for the apparent horizon in data sets with translational symmetry.
- 2 May 2024
- Published by IOP Publishing in Classical and Quantum Gravity
- Vol. 41 (11) , 115003
Open AccessSymmetry and instability of marginally outer trapped surfaces
We consider an initial data set having a continuous symmetry and a marginally outer trapped surface (MOTS) that is not preserved by this symmetry. We show that such a MOTS is unstable except in an exceptional case. In non-rotating cases we provide a Courant-type lower bound on the number of unstable eigenvalues. These results are then used to prove the instability of a large class of exotic MOTSs that were recently observed in the Schwarzschild spacetime. We also discuss the implications for the apparent horizon in data sets with translational symmetry.
- Open Access
Distorted static black holes with a bubble
We construct a family of local static, vacuum five-dimensional solutions with two commuting spatial isometries describing a black hole with a $S^3$ horizon and a 2-cycle `bubble' in the domain of outer communications. The solutions are obtained by adding distortions to an asymptotically flat seed solution. We show that the conical singularities in the undistorted geometry can be removed by an appropriate choice of the distortion.Open AccessDistorted static black holes with a bubble
We construct a family of local static, vacuum five-dimensional solutions with two commuting spatial isometries describing a black hole with a $S^3$ horizon and a 2-cycle `bubble' in the domain of outer communications. The solutions are obtained by adding distortions to an asymptotically flat seed solution. We show that the conical singularities in the undistorted geometry can be removed by an appropriate choice of the distortion. - Open Access
Symmetry and instability of marginally outer trapped surfaces
We consider an initial data set having a continuous symmetry and a marginally outer trapped surface (MOTS) that is not preserved by this symmetry. We show that such a MOTS is unstable except in an exceptional case. In non-rotating cases we provide a Courant-type lower bound on the number of unstable eigenvalues. These results are then used to prove the instability of a large class of exotic MOTSs that were recently observed in the Schwarzschild spacetime. We also discuss the implications for the apparent horizon in data sets with translational symmetry.
Open AccessSymmetry and instability of marginally outer trapped surfaces
We consider an initial data set having a continuous symmetry and a marginally outer trapped surface (MOTS) that is not preserved by this symmetry. We show that such a MOTS is unstable except in an exceptional case. In non-rotating cases we provide a Courant-type lower bound on the number of unstable eigenvalues. These results are then used to prove the instability of a large class of exotic MOTSs that were recently observed in the Schwarzschild spacetime. We also discuss the implications for the apparent horizon in data sets with translational symmetry.
- Open Access
Marginally Outer Trapped Tori in Black Hole Spacetimes
During a binary black hole merger, multiple intermediary marginally outer trapped tubes connect the initial pair of apparent horizons with the final (single) apparent horizon. The marginally outer trapped surfaces (MOTSs) that foliate these tubes can have complicated geometries as well as non-spherical topologies. In particular, toroidal MOTSs form inside both of the original black holes during the early stages of a head-on merger that starts from time-symmetric initial data [1]. We show that toroidal MOTSs also form in the maximal analytic extension of the Schwarzschild spacetime as Kruskal time advances from the $T=0$ moment of time symmetry. As for the merger simulations, they cross the Einstein-Rosen bridge and are tightly sandwiched between the apparent horizons in the two asymptotic regions at early times. This strongly suggests that their formation is a consequence of the initial conditions rather than merger physics. Finally, we consider MOTSs of spherical topology in the Kruskal-Szekeres slicing and study their properties. All of these are contained within the apparent horizon but some do not enclose the wormhole.Open AccessMarginally Outer Trapped Tori in Black Hole Spacetimes
During a binary black hole merger, multiple intermediary marginally outer trapped tubes connect the initial pair of apparent horizons with the final (single) apparent horizon. The marginally outer trapped surfaces (MOTSs) that foliate these tubes can have complicated geometries as well as non-spherical topologies. In particular, toroidal MOTSs form inside both of the original black holes during the early stages of a head-on merger that starts from time-symmetric initial data [1]. We show that toroidal MOTSs also form in the maximal analytic extension of the Schwarzschild spacetime as Kruskal time advances from the $T=0$ moment of time symmetry. As for the merger simulations, they cross the Einstein-Rosen bridge and are tightly sandwiched between the apparent horizons in the two asymptotic regions at early times. This strongly suggests that their formation is a consequence of the initial conditions rather than merger physics. Finally, we consider MOTSs of spherical topology in the Kruskal-Szekeres slicing and study their properties. All of these are contained within the apparent horizon but some do not enclose the wormhole. - Open Access
- 11 April 2023
- Published by IOP Publishing in Classical and Quantum Gravity
- Vol. 40 (9) , 095010
Exotic marginally outer trapped surfaces in rotating spacetimes of any dimension
The recently developed MOTSodesic method for locating marginally outer trapped surfaces (MOTSs) was effectively restricted to non-rotating spacetimes. In this paper we extend the method to include (multi-)axisymmetric time slices of (multi-)axisymmetric spacetimes of any dimension. We then apply this method to study MOTSs in the BTZ, Kerr and Myers–Perry black holes. While there are many similarities between the MOTSs observed in these spacetimes and those seen in Schwarzschild and Reissner-Nordström, details of the more complicated geometries also introduce some new, previously unseen, behaviours.
- 11 April 2023
- Published by IOP Publishing in Classical and Quantum Gravity
- Vol. 40 (9) , 095010
Open AccessExotic marginally outer trapped surfaces in rotating spacetimes of any dimension
The recently developed MOTSodesic method for locating marginally outer trapped surfaces (MOTSs) was effectively restricted to non-rotating spacetimes. In this paper we extend the method to include (multi-)axisymmetric time slices of (multi-)axisymmetric spacetimes of any dimension. We then apply this method to study MOTSs in the BTZ, Kerr and Myers–Perry black holes. While there are many similarities between the MOTSs observed in these spacetimes and those seen in Schwarzschild and Reissner-Nordström, details of the more complicated geometries also introduce some new, previously unseen, behaviours.