| 1. |
- Ananth, S., et al.
(author)
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A hidden symmetry in quantum gravity
- 2018
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In: Journal of High Energy Physics. - 1029-8479 .- 1126-6708. ; 2018:11
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Journal article (peer-reviewed)abstract
- The action integral contains more information than the equations of motion. Since it is an integral, changes of the integration variables occasionally also expose symmetries more easily than working directly with the equations of motion. We have previously shown that there are signs of an extended exceptional symmetry for N= 8 supergravity in four dimensions. The symmetry is such that the fields used in the Lagrangian are not representations of the symmetry. Instead one has to add representations to obtain a representation of the extended symmetry group. In this paper we discuss an extended symmetry in four-dimensional gravity which is the “Ehlers Symmetry” in three dimensions. It cannot be spanned by the helicity states of four-dimensional gravity but it can be realised once we treat the helicity states just as field variables of the functional integral, which can be changed like variables in any integral. We also explain how this symmetry is inherent in formulations of N= 8 supergravity in four dimensions through a truncation in the field space to pure gravity. The establishment of these “hidden” symmetries should play an important role in the perturbative behaviour of the quantum theories. Since the method used n this paper is purely algebraic we will not provide any information on the geometric role of these symmetries.
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| 2. |
- Ananth, Sudarshan, et al.
(author)
-
BMS algebra from residual gauge invariance in light-cone gravity
- 2021
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In: Journal of High Energy Physics. - 1029-8479 .- 1126-6708. ; 2021:11
-
Journal article (peer-reviewed)abstract
- We analyze the residual gauge freedom in gravity, in four dimensions, in the light-cone gauge, in a formulation where unphysical fields are integrated out. By checking the invariance of the light-cone Hamiltonian, we obtain a set of residual gauge transformations, which satisfy the BMS algebra realized on the two physical fields in the theory. Hence, the BMS algebra appears as a consequence of residual gauge invariance in the bulk and not just at the asymptotic boundary. We highlight the key features of the light-cone BMS algebra and discuss its connection with the quadratic form structure of the Hamiltonian.
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| 3. |
- Ananth, S., et al.
(author)
-
Bondi-Metzner-Sachs algebra as an extension of the Poincaré symmetry in light-cone gravity
- 2021
-
In: Journal of High Energy Physics. - 1029-8479 .- 1126-6708. ; 2021:7
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Journal article (peer-reviewed)abstract
- We analyze possible local extensions of the Poincaré symmetry in light-cone gravity in four dimensions. We use a formalism where we represent the algebra on the two physical degrees of freedom, one with helicity 2 and the other with helicity −2. The representation is non-linearly realized and one of the light-cone momenta is the Hamiltonian, which is hence a non-linear generator of the algebra. We find that this can be locally realized and the Poincaré algebra extended to the BMS symmetry without any reference to asymptotic limits.
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| 4. |
- Ananth, S., et al.
(author)
-
E 8 in N= 8 supergravity in four dimensions
- 2018
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In: Journal of High Energy Physics. - 1029-8479 .- 1126-6708. ; 2018:1
-
Journal article (peer-reviewed)abstract
- We argue that N= 8 supergravity in four dimensions exhibits an exceptional E 8(8) symmetry, enhanced from the known E 7(7) invariance. Our procedure to demonstrate this involves dimensional reduction of the N= 8 theory to d = 3, a field redefinition to render the E 8(8) invariance manifest, followed by dimensional oxidation back to d = 4.
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| 5. |
- Ananth, S., et al.
(author)
-
Eleven-dimensional supergravity in light-cone superspace
- 2005
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In: Journal of High Energy Physics. - : Springer Science and Business Media LLC. - 1029-8479 .- 1126-6708. ; 5:5, s. 56-71
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Journal article (peer-reviewed)abstract
- We show that Supergravity in eleven dimensions can be described in terms of a constrained superfield on the light-cone, without the use of auxiliary fields. We build its action to first order in the gravitational coupling constant \kappa, by "oxidizing" (N=8,d=4) Supergravity. This is simply achieved, as for N=4 Yang-Mills, by extending the transverse derivatives into superspace. The eleven-dimensional SuperPoincare algebra is constructed and a fourth order interaction is conjectured.
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| 6. |
- Ananth, S., et al.
(author)
-
Exceptional versus superPoincaré algebra as the defining symmetry of maximal supergravity
- 2016
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In: Journal of High Energy Physics. - 1029-8479 .- 1126-6708. ; 2016:3
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Journal article (peer-reviewed)abstract
- © 2016, The Author(s). We describe how one may use either the superPoincaré algebra or the exceptional algebra to construct maximal supergravity theories in the light-cone formalism. The d = 4 construction shows both symmetries albeit in a non-linearly realized manner. In d = 11, we find that we have to choose which of these two symmetries to use, in constructing the theory. In order to understand the other “unused” symmetry, one has to perform a highly non-trivial field redefinition. We argue that this shows that one cannot trust counterterm arguments that do not take the full symmetry of the theory into account. Finally we discuss possible consequences for Superstring theory and M-theory.
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| 7. |
- Ananth, S., et al.
(author)
-
Gravitation and quadratic forms
- 2017
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In: Journal of High Energy Physics. - : Springer Science and Business Media LLC. - 1029-8479 .- 1126-6708. ; 2017:3
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Journal article (peer-reviewed)abstract
- The light-cone Hamiltonians describing both pure (N = 0) Yang-Mills and N = 4 super Yang-Mills may be expressed as quadratic forms. Here, we show that this feature extends to theories of gravity. We demonstrate how the Hamiltonians of both pure gravity and N = 8 supergravity, in four dimensions, may be written as quadratic forms. We examine the effect of residual reparametrizations on the Hamiltonian and the resulting quadratic form.
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| 8. |
- Ananth, Sudarshan, et al.
(author)
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Maximal supergravity and the quest for finiteness
- 2018
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In: International Journal of Modern Physics D. - 0218-2718. ; 27:14
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Research review (peer-reviewed)abstract
- We show that N = 8 supergravity may possess an even larger symmetry than previously believed. Such an enhanced symmetry is needed to explain why this theory of gravity exhibits ultraviolet behavior reminiscent of the finite N = 4 Yang-Mills theory. We describe a series of three steps that leads us to this result.
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| 9. |
- Ananth, S., et al.
(author)
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Yang-Mills theories and quadratic forms
- 2015
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In: Journal of High Energy Physics. - 1029-8479 .- 1126-6708. ; 2015:8
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Journal article (peer-reviewed)abstract
- Abstract: We show that the Hamiltonian of (N=1, d = 10) super Yang-Mills can be expressed as a quadratic form in a very similar manner to that of the (N=4, d = 4) theory. We find a similar quadratic form structure for pure Yang-Mills theory but this feature, in the non-supersymmetric case, seems to be unique to four dimensions. We discuss some consequences of this feature. © 2015, The Author(s).
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| 10. |
- Antoniadis, I., et al.
(author)
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Extensions of the Poincare group
- 2011
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In: Journal of Mathematical Physics. - : AIP Publishing. - 1089-7658 .- 0022-2488. ; 52:7
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Journal article (peer-reviewed)abstract
- We construct an extension of the Poincare group which involves a mixture of internal and space-time supersymmetries. The resulting group is an extension of the superPoincare group with infinitely many generators which carry internal and space-time indices. It is a closed algebra since all Jacobi identities are satisfied and it has, therefore, explicit matrix representations. We investigate the massless case and construct the irreducible representations of the extended symmetry. They are divided into two sets, longitudinal and transversal representations. The transversal representations involve an infinite series of integer and half-integer helicities. Finally, we suggest an extension of the conformal group along the same line.
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