| 1. |
- Adawi, Tom, 1970, et al.
(författare)
-
Goldstone tensor modes
- 1998
-
Ingår i: J. High Energy Phys. 9902:001,1999.
-
Tidskriftsartikel (refereegranskat)abstract
- In the context of brane solutions of supergravity, we discuss a general method to introduce collective modes of any spin by exploiting a particular way of breaking symmetries. The method is applied to the D3, M2 and M5 branes and we derive explicit expressions for how the zero-modes enter the target space fields, verify normalisability in the transverse directions and derive the corresponding field equations on the brane. In particular, the method provides a clear understanding of scalar, spinor, and rank r tensorial Goldstone modes, chiral as well as non-chiral, and how they arise from the gravity, Rarita-Schwinger, and rank r+1 Kalb-Ramond tensor gauge fields, respectively. Some additional observations concerning the chiral tensor modes on the M5 brane are discussed.
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| 2. |
- Adawi, Tom, 1970, et al.
(författare)
-
Superembeddings, nonlinear supersymmetry and five-branes
- 1997
-
Ingår i: Int.J.Mod.Phys.A13:4691-4716,1998.
-
Tidskriftsartikel (refereegranskat)abstract
- We examine general properties of superembeddings, i.e., embeddings of supermanifolds into supermanifolds. The connection between an embedding procedure and the method of non-linearly realised supersymmetry is clarified, and we demonstrate how the latter arises as a special case of the former. As an illustration, the super-5-brane in 7 dimensions, containing a self-dual 3-form world-volume field strength, is formulated in both languages, and provides an example of a model where the embedding condition does not suffice to put the theory on-shell.
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| 3. |
- Bao, Ling, 1980, et al.
(författare)
-
A note on topological M5-branes and string-fivebrane duality
- 2008
-
Ingår i: Journal of High Energy Physics. - : Springer Science and Business Media LLC. - 1029-8479 .- 1126-6708. ; 2008:6, s. 11-
-
Tidskriftsartikel (refereegranskat)abstract
- We derive the stability conditions for the M5-brane in topological M-theory using k-symmetry. The non-linearly self-dual 3-form on the world-volume is necessarily non-vanishing, as is the case also for the 2-form field strengths on coisotropic branes in topological string theory. It is demonstrated that the self-duality is consistent with the stability conditions, which are solved locally in terms of a tensor in the representation 6 of SU(3) subset of G(2). The double dimensional reduction of the M5-brane is the D4-brane, and its direct reduction is an NS5-brane. We show that the equation of motion for the 3-form on the NS5-brane wrapping a Calabi-Yau space is exactly the Kodaira-Spencer equation, providing support for a string-fivebrane duality in topological string theory.
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| 4. |
- Bao, Ling, 1980, et al.
(författare)
-
A Note on Topological M5-branes and String-Fivebrane Duality
- 2006
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- We derive the stability conditions for the M5-brane in topological M-theory using kappa-symmetry. The non-linearly self-dual 3-form on the world-volume is necessarily non-vanishing, as is the case also for the 2-form field strengths on coisotropic branes in topological string theory. It is demonstrated that the self-duality is consistent with the stability conditions, which are solved locally in terms of a tensor in the representation 6 of SU(3) in G_2. The double dimensional reduction of the M5-brane is the D4-brane, and its direct reduction is an NS5-brane. We show that the equation of motion for the 3-form on the NS5-brane wrapping a Calabi-Yau space is exactly the Kodaira-Spencer equation, providing support for a string-fivebrane duality in topological string theory.
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| 5. |
- Bao, Ling, 1980, et al.
(författare)
-
Aspects of higher curvature terms and U-duality
- 2007
-
Ingår i: Classical and Quantum Gravity. - : IOP Publishing. - 0264-9381 .- 1361-6382. ; 25:9
-
Tidskriftsartikel (refereegranskat)abstract
- We discuss various aspects of dimensional reduction of gravity with theEinstein-Hilbert action supplemented by a lowest order deformation formed asthe Riemann tensor raised to powers two, three or four. In the case of R^2 wegive an explicit expression, and discuss the possibility of extended cosetsymmetries, especially SL(n+1,Z) for reduction on an n-torus to threedimensions. Then we start an investigation of the dimensional reduction of R^3and R^4 by calculating some terms relevant for the coset formulation, aiming inparticular towards E_8(8)/(Spin(16)/Z_2) in three dimensions and aninvestigation of the derivative structure. We emphasise some issues concerningthe need for the introduction of non-scalar automorphic forms in order torealise certain expected enhanced symmetries.
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| 6. |
- Bao, Ling, 1980, et al.
(författare)
-
Membranes for Topological M-Theory
- 2005
-
Ingår i: Journal of High Energy Physics.
-
Tidskriftsartikel (refereegranskat)abstract
- We formulate a theory of topological membranes on manifolds with G_2 holonomy. The BRST charges of the theories are the superspace Killing vectors (the generators of global supersymmetry) on the background with reduced holonomy G_2. In the absence of spinning formulations of supermembranes, the starting point is an N=2 target space supersymmetric membrane in seven euclidean dimensions. The reduction of the holonomy group implies a twisting of the rotations in the tangent bundle of the branes with ``R-symmetry'' rotations in the normal bundle, in contrast to the ordinary spinning formulation of topological strings, where twisting is performed with internal U(1) currents of the N=(2,2) superconformal algebra. The double dimensional reduction on a circle of the topological membrane gives the strings of the topological A-model (a by-product of this reduction is a Green-Schwarz formulation of topological strings). We conclude that the action is BRST-exact modulo topological terms and fermionic equations of motion. We discuss the role of topological membranes in topological M-theory and the relation of our work to recent work by Hitchin and by Dijkgraaf et al.
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| 7. |
- Bao, Ling, 1980, et al.
(författare)
-
Rigid Calabi-Yau threefolds, Picard Eisenstein series and instantons
- 2013
-
Ingår i: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 462:1
-
Konferensbidrag (refereegranskat)abstract
- Type IIA string theory compactified on a rigid Calabi-Yau threefold gives rise to a classical moduli space that carries an isometric action of U(2, 1). Various quantum corrections break this continuous isometry to a discrete subgroup. Focussing on the case where the intermediate Jacobian of the Calabi-Yau admits complex multiplication by the ring of quadratic imaginary integers script O signd, we argue that the remaining quantum duality group is an arithmetic Picard modular group PU(2, 1; script O signd). Based on this proposal we construct an Eisenstein series invariant under this duality group and study its non-Abelian Fourier expansion. This allows the prediction of non-perturbative effects, notably the contribution of D2- and NS5-brane instantons. The present work extends our previous analysis in 0909.4299 which was restricted to the special case of the Gaussian integers script O sign1 = ℤ[i].
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| 8. |
- Bao, Ling, 1980, et al.
(författare)
-
U-Duality and the Compactified Gauss-Bonnet Term
- 2007
-
Ingår i: Journal of High Energy Physics.
-
Tidskriftsartikel (refereegranskat)abstract
- We present the complete toroidal compactification of the Gauss-Bonnet Lagrangian from D dimensions to D-n dimensions. Our goal is to investigate the resulting action from the point of view of the "U-duality" symmetry SL(n+1,R) which is present in the tree-level Lagrangian when D-n=3. The analysis builds upon and extends the investigation of the paper [arXiv:0706.1183], by computing in detail the full structure of the compactified Gauss-Bonnet term, including the contribution from the dilaton exponents. We analyze these exponents using the representation theory of the Lie algebra sl(n+1,R) and determine which representation is the relevant one for quadratic curvature corrections. By interpreting the result of the compactification as a leading term in a large volume expansion of an SL(n+1,Z)-invariant action, we conclude that the overall exponential dilaton factor should not be included in the representation structure. As a consequence, all dilaton exponents correspond to weights of sl(n+1,R), which, nevertheless, remain on the positive side of the root lattice.
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| 9. |
- Bengtsson, Viktor, 1981, et al.
(författare)
-
U-duality Covariant Membranes
- 2004
-
Ingår i: J. High Energy Phys. 0502 (2005) 020.
-
Tidskriftsartikel (refereegranskat)abstract
- We outline a formulation of membrane dynamics in D=8 which is fully covariant under the U-duality group SL(2,Z) x SL(3,Z), and encodes all interactions to fields in the eight-dimensional supergravity, which is constructed through Kaluza--Klein reduction on T^3. Among the membrane degrees of freedom is an SL(2,R) doublet of world-volume 2-form potentials, whose quantised electric fluxes determine the membrane charges, and are conjectured to provide an interpretation of the variables occurring in minimal representations of U-duality groups. We solve the relevant equations for the action for a restricted class of supergravity backgrounds. Some comments are made on supersymmetry and lower dimensions.
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| 10. |
|
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| 11. |
- Berman, David S., et al.
(författare)
-
Holographic Noncommutativity
- 2000
-
Ingår i: J. High Energy Phys. ; 05, s. 002-
-
Tidskriftsartikel (refereegranskat)
|
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| 12. |
- Cederwall, Martin, 1961, et al.
(författare)
-
An action for the superfive-brane in D=11 supergravity
- 1997
-
Ingår i: J. High Energy Phys. 9804:007,1998.
-
Tidskriftsartikel (refereegranskat)abstract
- An alternative path is taken for deriving an action for the supersymmetric 5-brane in 11 dimensions. Selfduality does not follow from the action, but is consistent with the equations of motion for arbitrary supergravity backgrounds. The action involves a 2-form as well as a 5-form world-volume potential; inclusion of the latter makes the action, as well as the non-linear selfduality relation for the 3-form field strength, polynomial. The requirement of invariance under kappa-transformations determines the form of the selfduality relation, as well as the action. The formulation is shown to be equivalent to earlier formulations of 5-brane dynamics.
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| 13. |
|
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| 14. |
- Cederwall, Martin, 1961, et al.
(författare)
-
D=3, N=8 conformal supergravity and the Dragon window
- 2011
-
Ingår i: Journal of High Energy Physics. - 1029-8479 .- 1126-6708. ; 2011:9
-
Tidskriftsartikel (refereegranskat)abstract
- We give a superspace description of D=3, N=8 supergravity. The formulation is off-shell in the sense that the equations of motion are not implied by the superspace constraints (but an action principle is not given). The multiplet structure is unconventional, which we connect to the existence of a "Dragon window", that is modules occurring in the supercurvature but not in the supertorsion. According to Dragon's theorem this cannot happen above three dimensions. We clarify the relevance of this window for going on the conformal shell, and discuss some aspects of coupling to conformal matter.
|
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| 15. |
- Cederwall, Martin, 1961, et al.
(författare)
-
Finite tensor deformations of supergravity solitons
- 1998
-
Ingår i: J. High Energy Phys. 9902:003,1999.
-
Tidskriftsartikel (refereegranskat)abstract
- We consider brane solutions where the tensor degrees of freedom are excited. Explicit solutions to the full non-linear supergravity equations of motion are given for the M5 and D3 branes, corresponding to finite selfdual tensor or Born-Infeld field strengths. The solutions are BPS-saturated and half-supersymmetric. The resulting metric space-times are analysed.
|
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| 16. |
- Cederwall, Martin, 1961, et al.
(författare)
-
Generalised 11-Dimensional Supergravity
- 2000
-
Ingår i: proceedings of the Triangle Meeting ``Non-perturbative Methods in Field and String Theory'', NORDITA, Copenhagen, June 19-22, 2000, and the International Conference ``Quantization, Gauge Theory and Strings'' in memory of Efim Fradkin, Moscow, June 5-10, 2000..
-
Konferensbidrag (refereegranskat)
|
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| 17. |
- Cederwall, Martin, 1961, et al.
(författare)
-
Higher-dimensional loop algebras, non-abelian extensions and p-branes
- 1994
-
Ingår i: Nucl.Phys.B424 (1994) 97.
-
Tidskriftsartikel (refereegranskat)abstract
- We postulate a new type of operator algebra with a non-abelian extension. This algebra generalizes the Kac-Moody algebra in string theory and the Mickelsson-Faddeev algebra in three dimensions to higher-dimensional extended objects (p-branes). We then construct new BRST operators, covariant derivatives and curvature tensors in the higher-dimensional generalization of loop space.
|
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| 18. |
- Cederwall, Martin, 1961, et al.
(författare)
-
Low energy dynamics of monopoles in N=2 SYM with matter
- 1995
-
Ingår i: Mod.Phys.Lett. A11 (1996) 367.
-
Tidskriftsartikel (refereegranskat)abstract
- We derive, for N=2 super-Yang-Mills with gauge group SU(2) and massless matter, the supersymmetric quantum mechanical models describing the time evolution of multi-monopole configurations in the low energy approximation. This is a first step towards identifying the solitonic states mapped to fundamental excitations by duality in the model with four hypermultiplets in the fundamental representation.
|
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| 19. |
|
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| 20. |
- Cederwall, Martin, 1961, et al.
(författare)
-
On the Dirac-Born-Infeld action for D-branes
- 1996
-
Ingår i: Phys.Lett.B390:148-152,1997.
-
Tidskriftsartikel (refereegranskat)abstract
- In this note, we consider the reformulation of the Dirac-Born-Infeld action for a Dirichlet p-brane in Brink-Di Vecchia-Howe-Tucker form, i.e., including an independent non-propagating world-volume metric. When p>2, the action becomes non-polynomial. A closed expression is derived for p=3. For selfdual field-strengths, the DBI action is reproduced by an action with a simple F^2 term. We speculate on supersymmetrization of the D_3-brane action. We also give the governing equations for arbitrary p, and derive an implicit expression for the D_4-brane lagrangian.
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| 21. |
- Cederwall, Martin, 1961, et al.
(författare)
-
(p,q) five-branes in nonzero B-field
- 1999
-
Ingår i: J. High Energy Phys. 0001:037,2000.
-
Tidskriftsartikel (refereegranskat)abstract
- We consider type IIB (p,q) 5-branes in constant non-zero background tensor potentials, or equivalently, with finite constant field strength on the brane. At linear level, zero-modes are introduced and the physical degrees of freedom are found to be parametrised by a real 2- or 4-form field strength on the brane. An exact, SL(2;Z)-covariant solution to the full non-linear supergravity equations is then constructed. The resulting metric space-times are analysed, with special emphasis on the limiting cases with maximal values of the tensor. The analysis provides an answer to how the various background tensor fields are related to Born-Infeld degrees of freedom and to non-commutativity parameters.
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| 22. |
- Cederwall, Martin, 1961, et al.
(författare)
-
Pure spinors and D=6 super-Yang-Mills
- 2008
-
Ingår i: arxiv.org/abs/0801.1428.
-
Tidskriftsartikel (refereegranskat)abstract
- Pure spinor cohomology has been used to describe maximally supersymmetric theories, like D=10 super-Yang-Mills and D=11 supergravity. Supersymmetry closes on-shell in such theories, and the fields in the cohomology automatically satisfy the equations of motion. In this paper, we investigate the corresponding structure in a model with off-shell supersymmetry, N=1 super-Yang-Mills theory in D=6. Here, fields and antifields are obtained as cohomologies in different complexes with respect to the BRST operator Q. It turns out to be natural to enlarge the pure spinor space with additional bosonic variables, subject to some constraints generalising the pure spinor condition, in order to accommodate the different supermultiplets in the same generalised pure spinor wave-function. We construct another BRST operator, s, acting in the cohomology of Q, whose cohomology implies the equations of motion. We comment on the possible use of similar approaches in other models.
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| 23. |
- Cederwall, Martin, 1961, et al.
(författare)
-
Schwinger terms and cohomology of pseudodifferential operators
- 1994
-
Ingår i: Commun.Math.Phys. 175 (1996) 203.
-
Tidskriftsartikel (refereegranskat)abstract
- We study the cohomology of the Schwinger term arising in second quantization of the class of observables belonging to the restricted general linear algebra. We prove that, for all pseudodifferential operators in 3+1 dimensions of this type, the Schwinger term is equivalent to the ``twisted'' Radul cocycle, a modified version of the Radul cocycle arising in non-commutative differential geometry. In the process we also show how the ordinary Radul cocycle for any pair of pseudodifferential operators in any dimension can be written as the phase space integral of the star commutator of their symbols projected to the appropriate asymptotic component.
|
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| 24. |
- Cederwall, Martin, 1961, et al.
(författare)
-
Spinorial Cohomology and Maximally Supersymmetric Theories
- 2001
-
Ingår i: J. High Energy Phys.. ; 02, s. 009-
-
Tidskriftsartikel (refereegranskat)abstract
- Fields in supersymmetric gauge theories may be seen as elements in a spinorial cohomology. We elaborate on this subject, specialising to maximally supersymmetric theories, where the superspace Bianchi identities, after suitable conventional constraints are imposed, put the theories on shell. In these cases, the spinorial cohomologies describe in a unified manner gauge transformations, fields and possible deformations of the models, e.g. string-related corrections in an alpha' expansion. Explicit cohomologies are calculated for super-Yang-Mills theory in D=10, for the N=(2,0) tensor multiplet in D=6 and for supergravity in D=11, in the latter case from the point of view of both the super-vielbein and the super-3-form potential. The techniques may shed light on some questions concerning the alpha'-corrected effective theories, and result in better understanding of the role of the 3-form in D=11 supergravity.
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| 25. |
- Cederwall, Martin, 1961, et al.
(författare)
-
Spinorial cohomology of abelian d=10 super-Yang-Mills at alpha'^3
- 2002
-
Ingår i: J. High Energy Phys.. ; 12, s. 005-
-
Tidskriftsartikel (refereegranskat)abstract
- We compute the spinorial cohomology of ten-dimensional abelian SYM at order alpha'^3 and we find that it is trivial. Consequently, linear supersymmetry alone excludes the presence of alpha'^3-order corrections. Our result lends support to the conjecture that there may be a unique supersymmetric deformation of ordinary ten-dimensional abelian SYM.
|
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| 26. |
- Cederwall, Martin, 1961, et al.
(författare)
-
Supersymmetric Corrections to Eleven-Dimensional Supergravity
- 2004
-
Ingår i: J. High Energy Phys. 0505 (2005) 052.
-
Tidskriftsartikel (refereegranskat)abstract
- In this paper we study eleven-dimensional supergravity in its most general form. This is done by implementing manifest supersymmetry (and Lorentz invariance) through the use of the geometric (torsion and curvature) superspace Bianchi identities. These identities are solved to linear order in a deformation parameter introduced via the dimension zero supertorsion given in its most general form. The theory so obtained is referred to as the deformed theory (to avoid the previously used term "off-shell"). An important by-product of this result is that any higher derivative correction to ordinary supergravity of the same dimension as R^4, but not necessarily containing it, derived e.g. from M-theory, must appear in a form compatible with the equations obtained here. Unfortunately we have not yet much to say about the explicit structure of these corrections in terms of the fields in the massless supermultiplet. Our results are potentially powerful since if the dimension zero torsion could be derived by other means, our reformulation of the Bianchi identities as a number of algebraic relations implies that the full theory would be known to first order in the deformation, including the dynamics. We mention briefly some methods to derive the information needed to obtain explicit answers both in the context of supergravity and ten-dimensional super-Yang-Mills where the situation is better understood. Other relevant aspects like spinorial cohomology, the role of the 3- and 6-form potentials and the connection of these results to M2 and M5 branes are also commented upon.
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| 27. |
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| 28. |
|
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| 29. |
|
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| 30. |
- Chu, X., et al.
(författare)
-
Higgsing M2 to D2 with gravity: N=6 chiral supergravity from topologically gauged ABJM theory
- 2011
-
Ingår i: Journal of High Energy Physics. - 1029-8479 .- 1126-6708. ; 2011:4, s. Art. no 040-
-
Tidskriftsartikel (refereegranskat)abstract
- We present the higgsing of three-dimensional N = 6 superconformal ABJM type theories coupled to conformal supergravity, so called topologically gauged ABJM theory, thus providing a gravitational extension of previous work on the relation between N M2 and N D2-branes. The resulting N = 6 supergravity theory appears at a chiral point similar to that of three-dimensional chiral gravity introduced recently by Li, Song and Strominger, but with the opposite sign for the Ricci scalar term in the lagrangian. We identify the supersymmetry in the broken phase as a particular linear combination of the supersymmetry and special conformal supersymmetry in the original topologically gauged ABJM theory. We also discuss the higgsing procedure in detail paying special attention to the role played by the U(1) factors in the original ABJM model and the U(1) introduced in the topological gauging.
|
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| 31. |
- Chu, X., et al.
(författare)
-
Three-dimensional topologically gauged N=6 ABJM type theories
- 2010
-
Ingår i: Journal of High Energy Physics. - 1029-8479 .- 1126-6708. ; 2010:6, s. Art. no 057-
-
Tidskriftsartikel (refereegranskat)abstract
- In this paper we construct the N = 6 conformal supergravity in three dimensions from a set of Chern-Simons-like terms one for each of the graviton, gravitino, and R-symmetry gauge field and then couple this theory to the N = 6 superconformal ABJM theory. In a first step part of the coupled Lagrangian for this topologically gauged ABJM theory is derived by demanding that all terms of third and second order in covariant derivatives cancel in the supersymmtry variation of the Lagrangian. To achieve this the transformation rules of the two separate sectors must be augmented by new terms. In a second step we analyze all terms in delta L that are of first order in covariant derivatives. The cancelation of these terms require additional terms in the transformation rules as well as a number of new terms in the Lagrangian. As a final step we check that all remaining terms in dL which are bilinear in fermions cancel which means that the presented Lagrangian and transformation rules constitute the complete answer. In particular we find in the last step new terms in the scalar potential containing either one or no structure constant. The non-derivative higher fermion terms in delta L that have not yet been completely analyzed are briefly discussed in the Conclusions. A possible connection to chiral gravity is also mentioned there.
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| 32. |
- Ekhammar, Simon, et al.
(författare)
-
On the squashed seven-sphere operator spectrum
- 2021
-
Ingår i: Journal of High Energy Physics. - : Springer Nature. - 1029-8479 .- 1126-6708. ; 2021:12
-
Tidskriftsartikel (refereegranskat)abstract
- We derive major parts of the eigenvalue spectrum of the operators on the squashed seven-sphere that appear in the compactification of eleven-dimensional supergravity. These spectra determine the mass spectrum of the fields in AdS4 and are important for the corresponding N = 1 supermultiplet structure. This work is a continuation of the work in [1] where the complete spectrum of irreducible isometry representations of the fields in AdS4 was derived for this compactification. Some comments are also made concerning the G2 holonomy and its implications on the structure of the operator equations on the squashed seven-sphere.
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| 33. |
- Gran, Ulf, 1973, et al.
(författare)
-
Off-shell structure of twisted (2,0) theory
- 2014
-
Ingår i: Journal of High Energy Physics. - 1029-8479 .- 1126-6708. ; 2014:11
-
Tidskriftsartikel (refereegranskat)abstract
- A $Q$-exact off-shell action is constructed for twisted abelian (2,0) theory on a Lorentzian six-manifold of the form $M_{1,5} = C\times M_4$, where $C$ is a flat two-manifold and $M_4$ is a general Euclidean four-manifold. The properties of this formulation, which is obtained by introducing two auxiliary fields, can be summarised by a commutative diagram where the Lagrangian and its stress-tensor arise from the $Q$-variation of two fermionic quantities $V$ and $\lambda^{\mu\nu}$. This completes and extends the analysis in [arXiv:1311.3300].
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| 34. |
- Gran, Ulf, 1973, et al.
(författare)
-
On relating multiple M2 and D2-branes
- 2008
-
Ingår i: Journal of High Energy Physics. - : Springer Science and Business Media LLC. - 1029-8479 .- 1126-6708. ; 2008:10
-
Tidskriftsartikel (refereegranskat)abstract
- Due to the difficulties of finding superconformal Lagrangian theories for multiple M2-branes, we will in this paper instead focus on the field equations. By relaxing the requirement of a Lagrangian formulation we can explore the possibility of having structure constants fABCD satisfying the fundamental identity but which are not totally antisymmetric. We exemplify this discussion by making use of an explicit choice of a non-antisymmetric fABCD constructed from the Lie algebra structure constants fabc of an arbitrary gauge group. Although this choice of fABCD does not admit an obvious Lagrangian description, it does reproduce the correct SYM theory for a stack of N D2-branes to leading order in gYM−1 upon reduction and, moreover, it sheds new light on the centre of mass coordinates for multiple M2-branes.
|
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| 35. |
- Gran, Ulf, 1973, et al.
(författare)
-
Three-dimensional N=8 superconformal gravity and its coupling to BLG M2-branes
- 2009
-
Ingår i: Journal of High Energy Physics. - : Springer Science and Business Media LLC. - 1029-8479 .- 1126-6708. ; 2009:3
-
Tidskriftsartikel (refereegranskat)abstract
- This paper is concerned with the problem of coupling the N=8 superconformal Bagger-Lambert-Gustavsson (BLG) theory to N=8 conformal supergravity in three dimensions. We start by constructing the on-shell N=8 conformal supergravity in three dimensions consisting of a Chern-Simons type term for each of the gauge fields: the spin connection, the SO(8) R-symmetry gauge field and the spin 3/2 Rarita-Schwinger (gravitino) field. We then describe how to couple this minimally to the BLG theory. The final theory should have the same physical content, i.e., degrees of freedom, as the ordinary BLG theory. We discuss briefly the properties of this "topologically gauged" BLG theory and why this theory may be useful.
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| 36. |
- Gran, Ulf, 1973, et al.
(författare)
-
Topologically gauged superconformal Chern-Simons matter theories
- 2012
-
Ingår i: Journal of High Energy Physics (JHEP). - 1126-6708 .- 1029-8479. ; :12, s. 046-
-
Tidskriftsartikel (refereegranskat)abstract
- By coupling N = 8 superconformal matter to N = 8 superconformal Chern-Simons gravity in three dimensions we obtain theories with novel terms in the scalar potential leading to AdS(3) solutions and superconformal symmetry breaking. If we start from the theory derived by Bagger, Lambert and Gustavsson, our coupled theory either inherits the SO(4) gauge group or reduces it to SO(3). If the construction is instead based on a free matter theory we find that the gravitational topological gauging also requires the introduction of a Chern-Simons gauge sector resulting in a consistent theory for any SO(N) gauge group.
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| 37. |
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| 38. |
- Linander, Hampus, 1985, et al.
(författare)
-
The non-linear coupled spin 2 - spin 3 Cotton equation in three dimensions
- 2016
-
Ingår i: Journal of High Energy Physics. - 1029-8479 .- 1126-6708. ; 2016:7
-
Tidskriftsartikel (refereegranskat)abstract
- In the context of three-dimensional conformal higher spin theory we derive, in the frame field formulation, the full non-linear spin 3 Cotton equation coupled to spin 2. This is done by solving the corresponding Chern-Simons gauge theory system of equations, that is, using F=0 to eliminate all auxiliary fields and thus expressing the Cotton equation in terms of just the spin 3 frame field and spin 2 covariant derivatives and tensors (Schouten). In this derivation we neglect the spin 4 and higher spin sectors and approximate the star product commutator by a Poisson bracket. The resulting spin 3 Cotton equation is complicated but can be related to linearized versions in the metric formulation obtained previously by other authors. The expected symmetry (spin 3 "translation", "Lorentz" and "dilatation") properties are verified for Cotton and other relevant tensors but some perhaps unexpected features emerge in the process, in particular in relation to the non-linear equations. We discuss the structure of this non-linear spin 3 Cotton equation but its explicit form is only presented here, in an exact but not completely refined version, in appended files obtained by computer algebra methods. Both the frame field and metric formulations are provided.
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| 39. |
- Nilsson, Bengt E W, 1952
(författare)
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Aspects of topologically gauged M2-branes with six supersymmetries: towards a 'sequential AdS/CFT'?
- 2012
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Abstract: In this note we review the construction of topologically gauged M2 branes with 6 supersymmetries and discuss some of its properties. This is done using the 3- algebra formulation thereby covering all possible gauge groups. We will elaborate upon 1) the fundamental identity and its solutions noting, provided these gauged theories describe stacks of branes, the case of a single brane, 2) the chiral point solution to the field equations (occuring even for a single brane) that breaks the superconformal symmetries down to those of AdS3 (TMG) supergravity, 3) physical parameters and how they scale in the compactification from 11d to 10d and give rise to matter theories in curved space-times, and finally 4) a more speculative comment on ”sequential AdS/CFT”. Here we propose that the superconformal symmetry breaking in topologically gauged theories leads to the sequence AdS4/CFT3 → AdS3/CFT2 and that the higgsing in the 3d boundary theory is related to a change of foliation in the AdS4 bulk theory.
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| 40. |
- Nilsson, Bengt E W, 1952
(författare)
-
Critical solutions of topologically gauged N = 8 CFTs in three dimensions
- 2013
-
Ingår i: ArXiv/hepth. ; , s. 1304.2270-
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Abstract:In this paper we discuss some special (critical) background solutions that arise in topological gauged N = 8 three-dimensional CFTs with SO(N) gauge group. Depending on how many scalar fields are given a VEV the theory has background solutions for certain values of μl, where μ and l are parameters in the T M G Lagrangian. Apart from Minkowski, chiral round AdS3 and null-warped AdS3 (or Schro ̈dinger(z = 2)) we identify also a more exotic solution recently found in TMG by Ertl, Grumiller and Johansson. We also discuss the spectrum, symmetry breaking pattern and the supermultiplet structure in the various backgrounds and argue that some properties are due to their common origin in a conformal phase. Some of the scalar fields, including all higgsed ones, turn out to satisfy three-dimensional field equations similar to those of the singleton. Finally, we note that topologically gauged N = 6 ABJ(M) theories have a similar, but more restricted, set of background solutions.
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| 41. |
- Nilsson, Bengt E W, 1952
(författare)
-
Critical solutions of topologically gauged N=8 CFTs in three dimensions
- 2014
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Ingår i: Journal of High Energy Physics. - : Springer Science and Business Media LLC. - 1029-8479 .- 1126-6708. ; 2014:4
-
Tidskriftsartikel (refereegranskat)abstract
- In this paper we discuss some special (critical) background solutions that arise in topological gauged N = 8 three-dimensional CFTs with SO(N) gauge group. Depending on how many scalar fields are given a VEV the theory has background solutions for certain values of mu l, where mu and l are parameters in the T M G Lagrangian. Apart from Minkowski, chiral round AdS(3) and null-warped AdS(3) (or Schrodinger(z = 2)) we identify also a more exotic solution recently found in TMG by Ertl, Grumiller and Johansson. We also discuss the spectrum, symmetry breaking pattern and the supermultiplet structure in the various backgrounds and argue that some properties are due to their common origin in a conformal phase. Some of the scalar fields, including all higgsed ones, turn out to satisfy three-dimensional field equations similar to those of the singleton. Finally, we note that topologically gauged N = 6 ABJ(M) theories have a similar, but more restricted, set of background solutions.
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| 42. |
- Nilsson, Bengt E W, 1952, et al.
(författare)
-
Higgsing M2 to D2 with gravity: N=6 chiral supergravity from topologically gauged ABJM theory
- 2010
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Ingår i: arXiv:1012.5969 [hep-th].
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Abstract: We present the higgsing of three-dimensional N = 6 superconformal ABJM type theories coupled to conformal supergravity, so called topologically gauged ABJM theory, thus providing a gravitational extension of previous work on the relation between N M2 and N D2-branes. The resulting N = 6 supergravity theory appears at a chiral point similar to that of three-dimensional chiral gravity introduced recently by Li, Song and Strominger, but with the opposite sign for the Ricci scalar term in the lagrangian. We identify the supersymmetry in the broken phase as a particular linear combination of the supersymmetry and special conformal supersymmetry in the original topologically gauged ABJM theory. We also discuss the higgsing procedure in detail paying special attention to the role played by the U(1) factors in the original ABJM model and the U(1) introduced in the topological gauging
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| 43. |
- Nilsson, Bengt E W, 1952, et al.
(författare)
-
Instanton Corrections to the Universal Hypermultiplet and Automorphic Forms on SU(2,1).
- 2010
-
Ingår i: Communications in Number Theory and Physics. - 1931-4531 .- 1931-4523. ; 4:1, s. 187-266
-
Tidskriftsartikel (refereegranskat)abstract
- Abstract: The hypermultiplet moduli space in Type IIA string theory compactified on a rigid Calabi-Yau threefold X , corresponding to the “universal hypermultiplet”, is described at tree-level by the symmetric space SU(2,1)/(SU(2)×U(1)). To determine the quantum corrections to this metric, we posit that a discrete subgroup of the continuous tree-level isometry group SU(2,1), namely the Picard modular group SU(2,1;Z[i]), must remain un- broken in the exact metric – including all perturbative and non-perturbative quantum cor- rections. This assumption is expected to be valid when X admits complex multiplication by Z[i]. Based on this hypothesis, we construct an SU(2,1;Z[i])-invariant, non-holomorphic Eisenstein series, and tentatively propose that this Eisenstein series provides the exact contact potential on the twistor space over the universal hypermultiplet moduli space. We analyze its non-Abelian Fourier expansion, and show that the Abelian and non-Abelian Fourier coefficients take the required form for instanton corrections due to Euclidean D2- branes wrapping special Lagrangian submanifolds, and to Euclidean NS5-branes wrapping the entire Calabi-Yau threefold, respectively. While this tentative proposal fails to repro- duce the correct one-loop correction, the consistency of the Fourier expansion with physics expectations provides strong support for the usefulness of the Picard modular group in constraining the quantum moduli space.
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| 44. |
- Nilsson, Bengt E W, 1952
(författare)
-
Light-cone analysis of ungauged and topologically gauged BLG theories
- 2009
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Ingår i: Classical and Quantum Gravity. - : IOP Publishing. - 0264-9381 .- 1361-6382. ; 26:17
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Tidskriftsartikel (refereegranskat)abstract
- We consider three-dimensional maximally superconformal Bagger-Lambert-Gustavsson (BLG) theory and its topologically gauged version (constructed recently in Gran and Nilsson (2009 J. High Energy Phys. JHEP03(2009) 074 (arXiv:0809.4478 [hep-th]))) in the light-cone gauge. After eliminating the entire Chern-Simons gauge field, the ungauged BLG light-cone theory looks more conventional and, apart from the order of the interaction terms, resembles N = 4 super-Yang-Mills theory in four dimensions. The light-cone superspace version of the BLG theory is given at the quadratic order together with a suggested form for the quartic terms. Some problems with constructing the sixth-order interaction terms are also discussed. In the topologically gauged case, we analyze the field equations related to the three Chern-Simons-type terms of N = 8 conformal supergravity and discuss some of the special features of this theory and its couplings to BLG.
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| 45. |
- Nilsson, Bengt E W, 1952
(författare)
-
On the conformal higher spin unfolded equation for a three-dimensional self-interacting scalar field
- 2016
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Ingår i: Journal of High Energy Physics. - 1029-8479 .- 1126-6708. ; 2016:8, s. 142-
-
Tidskriftsartikel (refereegranskat)abstract
- We propose field equations for the conformal higher spin system in three dimensions coupled to a conformal scalar field with a sixth order potential. Both the higher spin equation and the unfolded equation for the scalar field have source terms and are based on a conformal higher spin algebra which we treat as an expansion in multi-commutators. Explicit expressions for the source terms are suggested and subjected to some simple tests. We also discuss a cascading relation between the Chern-Simons action for the higher spin gauge theory and an action containing a term for each spin that generalizes the spin 2 Chern-Simons action in terms of the spin connection expressed in terms of the frame field. This cascading property is demonstrated in the free theory for spin 3 but should work also in the complete higher spin theory.
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| 46. |
- Nilsson, Bengt E W, 1952, et al.
(författare)
-
Rigid Calabi-Yau threefolds, Picard Eisenstein series and instantons
- 2010
-
Ingår i: roceedings of 6th International Symposium on Quantum Theory and Symmetries (QTS6), Lexington, Kentucky, 20-25 Jul 2009..
-
Konferensbidrag (refereegranskat)abstract
- Abstract.Type IIA string theory compactified on a rigid Calabi-Yau threefold gives rise to a classical moduli space that carries an isometric action of U(2,1). Various quantum corrections break this continuous isometry to a discrete subgroup. Focussing on the case where the intermediate Jacobian of the Calabi-Yau admits complex multiplication by the ring of quadratic imaginary integers Od, we argue that the remaining quantum duality group is an arithmetic Picard modular group PU(2,1;Od). Based on this proposal we construct an Eisenstein series invariant under this duality group and study its non-Abelian Fourier expansion. This allows the prediction of non-perturbative effects, notably the contribution of D2- and NS5-brane instantons. The present work extends our previous analysis in 0909.4299 which was restricted to the special case of the Gaussian integers O1 = Z[i].
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| 47. |
- Nilsson, Bengt E W, 1952, et al.
(författare)
-
Superconformal M2-branes and generalized Jordan triple systems
- 2009
-
Ingår i: Classical and Quantum Gravity. - : IOP Publishing. - 0264-9381 .- 1361-6382. ; 26:7, s. Article Number: 075007 -
-
Tidskriftsartikel (refereegranskat)abstract
- Three-dimensional conformal theories with six supersymmetries and SU(4) R-symmetry describing stacks of M2-branes are here proposed to be related to generalized Jordan triple systems. Writing the four-index structure constants in an appropriate form, the Chern-Simons part of the action immediately suggests a connection to such triple systems. In contrast to the previously considered 3-algebras, the additional structure of a generalized Jordan triple system is associated with a graded Lie algebra, which corresponds to an extension of the gauge group. In this paper we show that the whole theory with six manifest supersymmetries can be naturally expressed in terms of such a graded Lie algebra. Also the Bagger, Lambert and Gustavsson theory with eight supersymmetries is included as a special case.
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| 48. |
- Nilsson, Bengt E W, 1952, et al.
(författare)
-
The role of singletons in S 7 compactifications
- 2019
-
Ingår i: Journal of High Energy Physics. - 1029-8479 .- 1126-6708. ; 2019:7
-
Tidskriftsartikel (refereegranskat)abstract
- We derive the isometry irrep content of squashed seven-sphere compactifications of eleven-dimensional supergravity, i.e., the left-squashed (LS7) with N = 1 and right-squashed (RS7) with N = 0 supersymmetry, in a manner completely independent of the round sphere. Then we compare this result with the spectrum obtained by Higgsing the round sphere spectrum. This way we discover features of the spectra which makes it possible to argue that the only way the round spectrum can be related by a Higgs mechanism to the one of LS7 is if the singletons are included in the round sphere spectrum. For this to work also in the RS7 case it seems that the gravitino of the LS7 spectrum must be replaced by a fermionic singleton present in the RS7 spectrum.
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| 49. |
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| 50. |
- Nilsson, Bengt E W, 1952
(författare)
-
Towards an exact frame formulation of conformal higher spins in three dimensions
- 2015
-
Ingår i: Journal of High Energy Physics. - 1029-8479 .- 1126-6708. ; 2015:9, s. Art. no. 78-
-
Tidskriftsartikel (refereegranskat)abstract
- In this note we discuss some aspects of the frame formulation of conformal higher spins in three dimensions. We give some exact formulae for the coupled spin two - spin three part of the full higher spin theory and propose a star product Lagrangian for all spins from two and up. Since there is no consistent Lagrangian formulation based on the Poisson bracket we start the construction from the field equations in this approximation of the star product. The higher spin algebra is then realized in terms of classical variables which leads to certain important simplifications that we take advantage of. The suggested structure of the all-spin Lagrangian given here is, however, obtained using an expansion of the star product beyond the Poisson bracket in terms of multi-commutators and the Lagrangian should be viewed as a starting point for the derivation of the full theory based on a star product. How to do this is explained as well as how to include the coupling to scalar fields. We also comment on the AdS/CFT relation to four dimensions.
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