P.K. Townsend

University of Cambridge, Cambridge, England, United Kingdom

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Publications (38)186.84 Total impact

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    K. Skenderis, P. K. Townsend
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    ABSTRACT: We use Hamiltonian methods to study curved domain walls and cosmologies. This leads naturally to first-order equations for all domain walls and cosmologies foliated by slices of maximal symmetry. For Minkowski and AdS-sliced domain walls (flat and closed FLRW cosmologies) we recover a recent result concerning their (pseudo)supersymmetry. We show how domain-wall stability is consistent with the instability of AdS vacua that violate the Breitenlohner-Freedman bound. We also explore the relationship to Hamilton-Jacobi theory and compute the wave-function of a 3-dimensional closed universe evolving towards de Sitter spacetime.
    Physical Review D 12/2006; 74:125008. · 4.69 Impact Factor
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    Kostas Skenderis, Paul K Townsend
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    ABSTRACT: The correspondence between domain-wall and cosmological solutions of gravity coupled to scalar fields is explained. Any domain wall solution that admits a Killing spinor is shown to correspond to a cosmology that admits a pseudo-Killing spinor: whereas the Killing spinor obeys a Dirac-type equation with hermitian `mass'-matrix, the corresponding pseudo-Killing spinor obeys a Dirac-type equation with a anti-hermitian `mass'-matrix. We comment on some implications of (pseudo)supersymmetry.
    Journal of Physics A Mathematical and Theoretical 11/2006; · 1.77 Impact Factor
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    G. W. Gibbons, P. K. Townsend
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    ABSTRACT: The (2k+2)-dimensional Einstein-Yang-Mills equations for gauge group SO(2k) (or SU(2) for k=2 and SU(3) for k=3) are shown to admit a family of spherically-symmetric magnetic monopole solutions, for both zero and non-zero cosmological constant Lambda, characterized by a mass m and a magnetic-type charge. The k=1 case is the Reissner-Nordstrom black hole. The k=2 case yields a family of self-gravitating Yang monopoles. The asymptotic spacetime is Minkowski for Lambda=0 and anti-de Sitter for Lambda<0, but the total energy is infinite for k>1. In all cases, there is an event horizon when m>m_c, for some critical mass $m_c$, which is negative for k>1. The horizon is degenerate when m=m_c, and the near-horizon solution is then an adS_2 x S^{2k} vacuum. Comment: 16 pp. Extensive revision to include case of non-zero cosmological constant and implications for adS/CFT. Numerous additional references
    Classical and Quantum Gravity 04/2006; · 3.56 Impact Factor
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    J. Gutowski, G. Papadopoulos, P. K. Townsend
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    ABSTRACT: A static minimal energy configuration of a super p-brane in a supersymmetric (n+1)-dimensional spacetime is shown to be a `generalized calibrated' submanifold. Calibrations in $\bE^{(1,n)}$ and $AdS_{n+1}$ are special cases. We present several M-brane examples. Comment: Revtex. 11 pp. Minor corrections made and references added. To appear in Phys. Rev. D
    Physical Review D 05/1999; · 4.69 Impact Factor
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    G. W. Gibbons, P. K. Townsend
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    ABSTRACT: We argue that the Wess-Zumino model with quartic superpotential admits stable static solutions in which three domain walls intersect at a junction. We derive an energy bound for such junctions and show that configurations saturating it preserve 14 supersymmetry.
    Physical Review Letters 01/1999; 83:1727-1730. · 7.73 Impact Factor
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    G.W. Gibbons, P.K. Townsend
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    ABSTRACT: We argue that the large n limit of the n-particle SU(1,1|2) superconformal Calogero model provides a microscopic description of the extreme Reissner–Nordström black hole in the near-horizon limit.
    Physics Letters B 12/1998; · 4.57 Impact Factor
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    J. P. Gauntlett, R. C. Myers, P. K. Townsend
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    ABSTRACT: We discuss some general features of black holes of five-dimensional supergravity, such as the first law of black hole mechanics. We also discuss some special features of rotating supersymmetric black holes. In particular, we show that the horizon is a non-singular, and {\sl non-rotating}, null hypersurface whose intersection with a Cauchy surface is a squashed 3-sphere. We find the Killing spinors of the near-horizon geometry and thereby determine the near-horizon isometry supergroup.
    Classical and Quantum Gravity 11/1998; · 3.56 Impact Factor
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    J. P. Gauntlett, R. C. Myers, P. K. Townsend
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    ABSTRACT: We present a new 1/8 supersymmetric intersecting M-brane solution of D=11 supergravity with two independent rotation parameters. The metric has a non-singular event horizon and the near-horizon geometry is AdS3×S3×S3×E2 (just as in the non-rotating case). We also present a method of determining the isometry supergroup of supergravity solutions from the Killing spinors and use it to show that for the near horizon solution it is D(2|1,α)×D(2|1,α) where α is the ratio of the two 3-sphere radii. We also consider various dimensional reductions of our solution, and the corresponding effect of these reductions on the Killing spinors and the isometry supergroups.
    Physical Review D 11/1998; 59(2). · 4.69 Impact Factor
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    G. Papadopoulos, P.K. Townsend
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    ABSTRACT: We derive a bound on the energy of the general (p, q)-supersymmeric two-dimensional massive sigma-model with torsion, in terms of the topological and Noether charges that appear as central charges in its supersymmetry algebra. The bound is saturated by soliton solutions of first-order Bogomol'nyi-type equations. This generalizes results obtained previously for p = q models without torsion. We give examples of massive (1, 1) models with torsion that have a group manifold as a target space. We show that they generically have multiple vacua and find an explicit soliton solution of an SU(2) model. We also construct a new class of zero-torsion massive (4, 4) models with multiple vacua and soliton solutions. In addition, we compute the metrics on the one-soliton moduli spaces for those cases for which soliton solutions are known explicitly, and discuss their interpretation.
    Nuclear Physics B 06/1998; · 4.33 Impact Factor
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    ABSTRACT: Generalized membrane solutions of D = 11 supergravity, for which the transverse space is a toric hyper-Kahler manifold, are shown to have IIB duals representing the intersection of parallel 3-branes with 5-branes whose orientations are determined by their charge vectors. These IIB solutions, which generically preserve 3/16 of the supersymmetry, can be further mapped to solutions of D = 11 supergravity representing the intersection of parallel membranes with any number of fivebranes at arbitrary angles. Alternatively, a subclass (corresponding to non-singular D = 11 solutions) can be mapped to solutions representing the intersection on a string of any number of D-5-branes at arbitrary angles, again preserving supersymmetry, as we verify in a special case by a quaternionic extension of the analysis of Berkooz, Douglas and Leigh. We also use similar methods to find new supersymmetric solutions of orthogonally intersecting branes.
    Nuclear Physics B 01/1997; · 4.33 Impact Factor
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    G. Papadopoulos, P.K. Townsend
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    ABSTRACT: The M-theory interpretation of certain D = 10 IIA p-branes implies the existence of worldvolume Kaluza-Klein modes which are expected to appear as 0-brane/p-brane bound states preserving of the spacetime supersymmetry. We construct the corresponding solutions of the effective supergravity theory for p = 1,4, and show that no such solution exists for p = 8.
    Physics Letters B 09/1996; · 4.57 Impact Factor
  • G. Papadopoulos, P.K. Townsend
    Physics Letters B 07/1996; 380(3). · 4.57 Impact Factor
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    G. Papadopoulos, P.K. Townsend
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    ABSTRACT: We present the magnetic duals of Güven's electric-type solutions of D = 11 supergravity preserving or of the D = 11 supersymmetry. We interpret the electric solutions as n orthogonal intersecting membranes and the magnetic solutions as n orthogonal intersecting 5-branes, with n = 2, 3; these cases obey the general rule that p-branes can self-intersect on (p − 2)-branes. On reduction to D = 4 these solutions become electric or magnetic dilaton black holes with dilaton coupling constant a = 1 (for n = 2) or (for n = 3). We also discuss the reduction to D = 10.
    Physics Letters B 03/1996; · 4.57 Impact Factor
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    P.K. Townsend
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    ABSTRACT: A review is given of the implications of supersymmetric black holes for the non-perturbative formulation of toroidally compactified superstrings, with particular emphasis on symmetry enhancement at special vacua and S-duality of the heterotic string.
    Nuclear Physics B - Proceedings Supplements 10/1995; · 0.88 Impact Factor
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    G. Papadopoulos, P.K. Townsend
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    ABSTRACT: We investigate the compactification of D = 11 supergravity to D = 5,4,3, on compact manifolds of holonomy SU(3) (Calabi-Yau), G2, and Spin(7), respectively, making use of examples of the latter two cases found recently by Joyce. In each case the lower dimensional theory is a Maxwell/Einstein supergravity theory. We find evidence for an equivalence, in certain cases, with heterotic string compactifications from D = 10 to D = 5,4,3, on compact manifolds of holonomy SU(2) (K3 × S1), SU(3), and G2, respectively. Calabi-Yau manifolds with Hodge numbers h1,1 = h1,2 = 19 play a significant role in the proposed equivalences.
    Physics Letters B 06/1995; · 4.57 Impact Factor
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    G.W. Gibbons, P.K. Townsend
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    ABSTRACT: We show that the exact static, i.e. ‘anti-gravitating’, magnetic multi monopole solutions of the Einstein/Maxwell/dilaton-YM/Higgs equations found by Kastor, London, Traschen, and the authors, for arbitrary non-zero dilaton coupling constant a, are equivalent to the string theory BPS magnetic monopole solutions of Harvey and Liu when . For this value of a, the monopole solutions also solve the equations of five-dimensional supergravity/YM theory. We also discuss some features of the dyon solutions obtained by boosting in the fifth dimension and some features of the moduli space of anti-gravitating multi-monopoles.
    Physics Letters B 06/1995; · 4.57 Impact Factor
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    P.K. Townsend
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    ABSTRACT: The conjectured equivalence of the heterotic string to a K3 compactified type IIA superstring is combined with the conjectured equivalence of the latter to a compactified 11-dimensional supermembrane to derive a string membrane duality in seven dimensions; the membrane is a soliton of the string theory and vice versa. A prediction of this duality is that the heterotic string is a K3 compactification of the solitonic 11-dimensional fivebrane. It is verified that the worldsheet action of the D = 10 heterotic string is indeed obtainable by K3 compactification of the worldvolume action of the 11-dimensional fivebrane, and it is suggested how the worldvolume action of the D = 11 supermebrane may be similarly obtained by T3 compactification of the worldvolume action of a D = 10 heterotic fivebrane. Generalizations to D = 8 string-threebrane and membrane-membrane duality are also discussed.
    Physics Letters B 04/1995; · 4.57 Impact Factor
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    G. W. Gibbons, Gary T. Horowitz, P. K. Townsend
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    ABSTRACT: We show that the four-dimensional extreme dilaton black hole with dilaton coupling constant $a= \sqrt{p/(p+2)}$ can be interpreted as a {\it completely non-singular}, non-dilatonic, black $p$-brane in $(4+p)$ dimensions provided that $p$ is {\it odd}. Similar results are obtained for multi-black holes and dilatonic extended objects in higher spacetime dimensions. The non-singular black $p$-brane solutions include the self-dual three brane of ten-dimensional N=2B supergravity and a multi-fivebrane solution of eleven-dimensional supergravity. In the case of a supersymmetric non-dilatonic $p$-brane solution of a supergravity theory, we show that it saturates a bound on the energy per unit $p$-volume. Comment: 27 pages, R/94/28, UCSBTH-94-35 (Comments added to the discussion section)
    Classical and Quantum Gravity 10/1994; · 3.56 Impact Factor
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    M.J. Duff, G.W. Gibbons, P.K. Townsend
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    ABSTRACT: It is known that, in string sigma-model metric, the ‘extreme’ fivebrane solution of D = 10 supergravity interpolates between D = 10 Minkowski spacetime and a supersymmetric S3 compactification to a linear dilaton vacuum. We show here that, in fivebrane sigma-model metric, the extreme string solution of D = 10 supergravity interpolates between Minkowski spacetime and a hitherto unknown supersymmetric S7 compactification of d = 10 supergravity to a three-dimensional anti-de Sitter generalization of the linear dilaton vacuum, which may be invariantly characterized in terms of conformal Killing vectors. The dilaton field diverges near the string core but this divergence may be eliminated by re-interpreting the string solution as the extreme membrane solution of 11-dimensional supergravity. We show that the latter has an analytic extension through a regular degenerate event horizon to an interior region containing a curvature singularity. We obtain analogous results for other extended object solutions of supergravity theories.
    Physics Letters B 05/1994; · 4.57 Impact Factor
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    GW Gibbons, PK Townsend
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    ABSTRACT: We show that many of the recently proposed supersymmetric p-brane solutions of d=10 and d=11 supergravity have the property that they interpolate between Minkowski spacetime and a compactified spacetime, both being supersymmetric supergravity vacua. Our results imply that the effective worldvolume action for small fluctuations of the super p-brane is a supersingleton field theory for $(adS)_{p+2}$, as has been often conjectured in the past. Comment: 8pp
    Physical Review Letters 01/1994; 71(23):3754-3757. · 7.73 Impact Factor

Publication Stats

3k Citations
186.84 Total Impact Points

Institutions

  • 1986–2006
    • University of Cambridge
      • Department of Applied Mathematics and Theoretical Physics
      Cambridge, England, United Kingdom
  • 1998
    • University of California, Santa Barbara
      • Kavli Institute for Theoretical Physics
      Santa Barbara, CA, United States