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Papers by Chris Pope

The Rehabilitation Services Administration (RSA) administers and supports a comprehensive array o... more The Rehabilitation Services Administration (RSA) administers and supports a comprehensive array of formula and discretionary grant programs and projects that serve and assist individuals with disabilities.

Translation and the Sustainable Development Goals

SecEd, 2014

On Monday, the Prince's Teaching Institute is to unveil its blueprint for the proposed Colleg... more On Monday, the Prince's Teaching Institute is to unveil its blueprint for the proposed College of Teaching. Chris Pope gives us a sneak preview.

Pediatric Rheumatology, 2011

Nuclear Physics B, 2009

We construct new stationary Ricci-flat metrics of cohomogeneity 2 in five dimensions, which gener... more We construct new stationary Ricci-flat metrics of cohomogeneity 2 in five dimensions, which generalise the Myers-Perry rotating black hole metrics by adding a further non-trivial parameter. We obtain them via a construction that is analogous to the construction by Plebanski and Demianski in four dimensions of the most general type D metrics. Limiting cases of the new metrics contain not only the general Myers-Perry black hole with independent angular momenta, but also the single rotation black ring of Emparan and Reall. In another limit, we obtain new static metrics that describe black holes whose horizons are distorted lens spaces L(n; m) = S 3 /Γ(n; m), where m ≥ n + 2 ≥ 3. They are asymptotic to Minkowski spacetime factored by Γ(m; n). In the general stationary case, by contrast, the new metrics describe spacetimes with an horizon and with a periodicity condition on the time coordinate; these examples can be thought of as five-dimensional analogues of the four-dimensional Taub-NUT metrics.

Journal of High Energy Physics, 2009

In this paper, which is an elaboration of our results in hep-th/0504225, we construct new Einstei... more In this paper, which is an elaboration of our results in hep-th/0504225, we construct new Einstein-Sasaki spaces L p,q,r 1 ,•••,r n−1 in all odd dimensions D = 2n + 1 ≥ 5. They arise by taking certain BPS limits of the Euclideanised Kerr-de Sitter metrics. This yields local Einstein-Sasaki metrics of cohomogeneity n, with toric U (1) n+1 principal orbits, and n real non-trivial parameters. By studying the structure of the degenerate orbits we show that for appropriate choices of the parameters, characterised by the (n + 1) coprime inte

Journal of High Energy Physics, 2011

We construct N = 1 supersymmetrisations of some recently-proposed theories of critical gravity, c... more We construct N = 1 supersymmetrisations of some recently-proposed theories of critical gravity, conformal gravity, and extensions of critical gravity in four dimensions. The total action consists of the sum of three separately off-shell supersymmetric actions containing Einstein gravity, a cosmological term and the square of the Weyl tensor. For generic choices of the coefficients for these terms, the excitations of the resulting theory around an AdS 4 background describe massive spin-2 and massless spin-2 modes coming from the metric; massive spin-1 modes coming from a vector field in the theory; and massless and massive spin-3 2 modes (with two unequal masses) coming from the gravitino. These assemble into a massless and a massive N = 1 spin-2 multiplet. In critical supergravity, the coefficients are tuned so that the spin-2 mode in the massive multiplet becomes massless. In the supersymmetrised extensions of critical gravity, the coefficients are chosen so that the massive modes lie in a "window" of lowest energies E 0 such that these ghostlike fields can be truncated by imposing appropriate boundary conditions at infinity, thus leaving just positive-norm massless supergravity modes. Contents 1 Introduction 2 Off-Shell Supersymmetrisation of Cosmological Einstein plus Weyl-squared Gravity 3 Equations of Motion and Linearisation around AdS 4

Physics Letters B, 1990

The Wu algebras are extensions of the Virasoro algebra in which conformal fields of all spins 2, ... more The Wu algebras are extensions of the Virasoro algebra in which conformal fields of all spins 2, 3, ..., N occur. In this paper we investigate the form of the algebra obtained in the limit N-~. Utilizing an approach involving the direct imposition of Jacobi identities, we display complete and explicit expressions for all structure constants, including central extensions.

Physical Review Letters, 2004

We present the metric for a rotating black hole with a cosmological constant and with arbitrary a... more We present the metric for a rotating black hole with a cosmological constant and with arbitrary angular momenta in all higher dimensions. The metric is given in both Kerr-Schild and Boyer-Lindquist form. In the Euclidean-signature case, we also obtain smooth compact Einstein spaces on associated S D−2 bundles over S 2 , infinitely many for each odd D ≥ 5. Applications to string theory and M-theory are indicated.

Nuclear Physics B, 2001

We show that four-dimensional N = 2 ungauged Einstein-Maxwell supergravity can be embedded on the... more We show that four-dimensional N = 2 ungauged Einstein-Maxwell supergravity can be embedded on the Randall-Sundrum 3-brane, as a consistent Kaluza-Klein reduction of five-dimensional N = 4 gauged supergravity. In particular, this allows us to describe fourdimensional Reissner-Nordström black holes within the Randall-Sundrum scenario. Using earlier results on the embedding of five-dimensional N = 4 gauged supergravity in ten dimensions, we can then describe the four-dimensional Einstein-Maxwell supergravity on the 3-brane, and its solutions, from a type IIB viewpoint. We also show that the minimal ungauged supergravities in D = 5 and D = 6 can be consistently embedded in the halfmaximally supersymmetric gauged supergravities in D = 6 and D = 7 respectively. These allow us to construct solutions including BPS black holes and strings living in "Randall-Sundrum 4-branes," and BPS self-dual strings living in "Randall-Sundrum 5-branes." We can also lift the embeddings to ten-dimensional massive type IIA and D = 11 supergravity respectively. In particular, we obtain a solution describing the self-dual string living in the world-volume of an M5-brane.

Nuclear Physics B, 1998

We show that there exist nonlinearly realised duality symmetries that are independent of the stan... more We show that there exist nonlinearly realised duality symmetries that are independent of the standard supergravity global symmetries, and which provide active spectrum-generating symmetries for the fundamental BPS solitons. The additional ingredient, in any spacetime dimension, is a single scaling transformation that allows one to map between BPS solitons with different masses. Without the inclusion of this additional transformation, which is a symmetry of the classical equations of motion, but not the action, it is not possible to find a spectrum-generating symmetry. The necessity of including this scaling transformation highlights the vulnerability of duality multiplets to quantum anomalies. We argue that fundamental BPS solitons may be immune to this threat.

Nuclear Physics B, 2007

The four-dimensional Kerr-de Sitter and Kerr-AdS black hole metrics have cohomogeneity 2, and the... more The four-dimensional Kerr-de Sitter and Kerr-AdS black hole metrics have cohomogeneity 2, and they admit a generalisation in which an additional parameter characterising a NUT charge is included. In this paper, we study the higher-dimensional Kerr-AdS metrics, specialised to cohomogeneity 2 by appropriate restrictions on their rotation parameters, and we show how they too admit a generalisation in which an additional NUT-type parameter is introduced. We discuss also the supersymmetric limits of the new metrics. If one performs a Wick rotation to Euclidean spacetime signature, these yield new Einstein-Sasaki metrics in odd dimensions, and Ricci-flat metrics in even dimensions. We also study the five-dimensional Kerr-AdS black holes in detail. Although in this particular case the NUT parameter is trivial, our investigation reveals the remarkable feature that a five-dimensional Kerr-AdS "over-rotating" metric is equivalent, after performing a coordinate transformation, to an under-rotating Kerr-AdS metric.

Journal of Psychosomatic Research, 1984

A simple and standardised measure of perceived health status, the Nottingham Health Profile, was ... more A simple and standardised measure of perceived health status, the Nottingham Health Profile, was used to assess the effect on perceived health status of surgical intervention in a variety of non-acute medical disorders. Patients were assessed a few days before their operation and again two months later and were compared with a control group who had not undergone surgery. Results showed very little change in subjective health from before to after surgical intervention. The experimental group had similar perceived health scores to the control group on the pre-and post-tests. It is suggested that the period allowed to elapse after surgical intervention was too short, or that the level of problems experienced by patients prior to surgery was too low to show significant change. It is also possible that the particular presenting disorders were only one possible somatic representation of general feelings of minor ill-health in the group. The findings of this study point to the need to look at the differences between doctors and patients expectations of the outcome of surgery, the decision to seek care and the factors that govern wellbeing.

Classical and Quantum Gravity, 1994

Nilpotent BRST operators for higher-spin W 2,s strings, with currents of spins 2 and s, have rece... more Nilpotent BRST operators for higher-spin W 2,s strings, with currents of spins 2 and s, have recently been constructed for s = 4, 5 and 6. In the case of W 2,4 , this operator can be understood as being the BRST operator for the critical WB 2 string. In this paper, we construct a generalised BRST operator that can be associated with a non-critical W 2,4 string, in which WB 2 matter is coupled to the WB 2 gravity of the critical case. We also obtain the complete cohomology of the critical W 2,4 BRST operator, and investigate the physical spectra of the s = 5 and s = 6 string theories.

Classical and Quantum …, 2000

We make a detailed investigation of all spaces Q q 1 •••q N n 1 •••n N of the form of U (1) bundl... more We make a detailed investigation of all spaces Q q 1 •••q N n 1 •••n N of the form of U (1) bundles over arbitrary products i CP n i of complex projective spaces, with arbitrary winding numbers q i over each factor in the base. Special cases, including Q 11 11 (sometimes known as T 11), Q 111 111 and Q 32 21 , are relevant for compactifications of type IIB and D = 11 supergravity. Remarkable "conspiracies" allow consistent Kaluza-Klein S 5 , S 4 and S 7 sphere reductions of these theories that retain all the Yang-Mills fields of the isometry group in a massless truncation. We prove that such conspiracies do not occur for the reductions on the Q q 1 •••q N n 1 •••n N spaces, and that it is inconsistent to make a massless truncation in which the non-abelian SU (n i + 1) factors in their isometry groups are retained. In the course of proving this we derive many properties of the spaces Q q 1 •••q N n 1 •••n N of more general utility. In particular, we show that they always admit Einstein metrics, and that the spaces where q i = (n i + 1)/ all admit two Killing spinors. We also obtain an iterative construction for real metrics on CP n , and construct the Killing vectors on Q q 1 •••q N n 1 •••n N in terms of scalar eigenfunctions on CP n i. We derive bounds that allow us to prove that certain Killing-vector identities on spheres, necessary for consistent Kaluza-Klein reductions, are never satisfied on Q q 1 •••q N n 1 •••n N .

Physics Letters B, 1989

We exam1ne the re1at10n 6etween the a19e6ra 0f area-pre5erv1n9 d1ffe0m0rph15m5 0f a tw0-d1men510n... more We exam1ne the re1at10n 6etween the a19e6ra 0f area-pre5erv1n9 d1ffe0m0rph15m5 0f a tw0-d1men510na15urface and the a19e6ra 0f 5U (N) a5 N tend5 t0 1nf1n1ty. We 5h0w that the area-pre5erv1n9 a19e6ra 0f the 5phere 15 e4u1va1ent t0 5U + (¢~), wh115t that 0f the t0ru515 e4u1va1ent t0 5U (~).

The non-Abelian plane waves, first found in flat spacetime by Coleman and subsequently generalize... more The non-Abelian plane waves, first found in flat spacetime by Coleman and subsequently generalized to give pp-waves in Einstein-Yang-Mills theory, are shown to be 1/2 supersymmetric solutions of a wide variety of N=1 supergravity theories coupled to scalar and vector multiplets, including the theory of SU(2) Yang-Mills coupled to an axion \sigma and dilaton \phi recently obtained as the reduction to four-dimensions of the six-dimensional Salam-Sezgin model. In this latter case they provide the most general supersymmetric solution. Passing to the Riemannian formulation of this theory we show that the most general supersymmetric solution may be constructed starting from a self-dual Yang-Mills connection on a self-dual metric and solving a Poisson equation for e^\phi. We also present the generalization of these solutions to non-Abelian AdS pp-waves which allow a negative cosmological constant and preserve 1/4 of supersymmetry.