We consider three dimensional N = 4 flat supergravity, with an abelian R-symmetry enhancing the g... more We consider three dimensional N = 4 flat supergravity, with an abelian R-symmetry enhancing the gravitational phase space. We obtain the field configuration whose asymptotic symmetries at null infinity coincide with the centrally extended N = 4 super Bondi-Metzner-Sachs (BMS) algebra. The killing spinors for this generic configuration are obtained together with the energy bounds imposed by supersymmetry. It is explicitly shown that the same algebra can be obtained as a flat (AdS radius → ∞ ) limit of the combined (2, 0) and (0, 2) sectors of AdS supergravity.
We write down the 48+48 component multiplet of supercurrents for a rigid N=2 tensor multiplet in ... more We write down the 48+48 component multiplet of supercurrents for a rigid N=2 tensor multiplet in four spacetime dimensions along with its supersymmetry transformation law. This gives us the transformation of the linearized supergravity multiplet which couples to this supercurrent multiplet. At the linearized level, this 48+48 component supergravity multiplet decouples into the 24+24 component linearized standard Weyl multiplet known in the literature and a new 24+24 component irreducible multiplet that contains a dilaton and dilatino. By a consistent application of the supersymmetry algebra with field dependent structure constants appropriate to N=2 conformal supergravity, we find the full transformation law for this newly found multiplet. We present a set of constraints which can be consistently imposed on the new multiplet to obtain a restricted minimal 8+8 off-shell matter multiplet. We also show as an example the precise embedding of the tensor multiplet inside the new multiplet.
We consider three dimensional N = 4 flat supergravity, with an abelian R-symmetry enhancing the g... more We consider three dimensional N = 4 flat supergravity, with an abelian R-symmetry enhancing the gravitational phase space. We obtain the field configuration whose asymptotic symmetries at null infinity coincide with the centrally extended N = 4 super Bondi-Metzner-Sachs (BMS) algebra. The killing spinors for this generic configuration are obtained together with the energy bounds imposed by supersymmetry. It is explicitly shown that the same algebra can be obtained as a flat (AdS radius → ∞ ) limit of the combined (2, 0) and (0, 2) sectors of AdS supergravity. nabamita@iiserpune.ac.inivano@iiserpune.ac.inturmoli.neogi@students.iiserpune.ac.in
We consider the maximal $\cal{N}-$extended supergravity theory in 3 dimensions with fermionic gen... more We consider the maximal $\cal{N}-$extended supergravity theory in 3 dimensions with fermionic generators transforming under real but non necessarily irreducible representations of the internal algebra. We obtain the symmetry algebra at null infinity preserving boundary conditions of asymptotically flat solutions, i.e. the maximal $\cal{N}-$extended super-BMS$_3$ algebra, which possesses non-linear correction in the anti-commutators of supercharges. We present the supersymmetric energy bound and derive the explicit form of the asymptotic Killing spinors. We also find the most generic circular symmetric ground state of the theory, which corresponds to a non-supersymmetric cosmological solutions and derive their entropy.
Starting from the 48 þ 48 component multiplet of supercurrents for a rigid N ¼ 2 tensor multiplet... more Starting from the 48 þ 48 component multiplet of supercurrents for a rigid N ¼ 2 tensor multiplet in four spacetime dimensions, we obtain the transformation of the linearized supergravity multiplet which couples to this supercurrent multiplet. At the linearized level, this 48 þ 48 component supergravity multiplet decouples into the 24 þ 24 component linearized standard Weyl multiplet and a 24 þ 24 component irreducible matter multiplet containing a real scalar field. By a consistent application of the supersymmetry algebra with field-dependent structure constants appropriate to N ¼ 2 conformal supergravity, we find the full transformation law for this multiplet in a conformal supergravity background. By performing a suitable field redefinition, we find that the multiplet is a generalization of the flat space multiplet, obtained by Howe et al. in Nucl. Phys. B214, 519 (1983), to a conformal supergravity background. We also present a set of constraints which can be consistently imposed on this multiplet to obtain a restricted minimal 8 þ 8 off-shell matter multiplet. We also show, as an example, the precise embedding of the tensor multiplet inside this multiplet.
We continue the effort of defining and evaluating the quantum entropy function for supersymmetric... more We continue the effort of defining and evaluating the quantum entropy function for supersymmetric black holes in 4d $$ \mathcal{N} $$ N = 2 gauged supergravity, initiated in [1]. The emphasis here is on the missing steps in the previous localization analysis, mainly dealing with one-loop determinants for abelian vector multiplets and hypermultiplets on the non-compact space ℍ2× Σg with particular boundary conditions. We use several different techniques to arrive at consistent results, which have a most direct bearing on the logarithmic correction terms to the Bekenstein-Hawking entropy of said black holes.
We construct the dilaton Weyl multiplet for N = 2 conformal supergravity in four dimensions. Begi... more We construct the dilaton Weyl multiplet for N = 2 conformal supergravity in four dimensions. Beginning from an on-shell vector multiplet coupled to the standard Weyl multiplet, the equations of motion can be used to eliminate the supergravity auxiliary fields, following a similar pattern as in five and six dimensions. The resulting 24+24 component multiplet includes two gauge vectors and a gauge two-form and provides a variant formulation of N = 2 conformal supergravity. We also show how this dilaton Weyl multiplet is contained in the minimal 32+32 Poincaré supergravity multiplet introduced by Müller [1] in superspace.
We consider the maximal $$ \mathcal{N} $$ N -extended supergravity theory in 3 dimensions with fe... more We consider the maximal $$ \mathcal{N} $$ N -extended supergravity theory in 3 dimensions with fermionic generators transforming under real but non necessarily irreducible representations of the internal algebra. We obtain the symmetry algebra at null infinity preserving boundary conditions of asymptotically flat solutions, i.e. the maximal $$ \mathcal{N} $$ N -extended super-BMS3 algebra, which possesses non-linear correction in the anti-commutators of supercharges. We present the supersymmetric energy bound and derive the explicit form of the asymptotic Killing spinors. We also find the most generic circular symmetric ground state of the theory, which corresponds to a non-supersymmetric cosmological solutions and derive their entropy.
We analyze BPS black hole attractors in 4d gauged supergravity in the presence of higher derivati... more We analyze BPS black hole attractors in 4d gauged supergravity in the presence of higher derivative supersymmetric terms, including a Weyl-squared-type action, and determine the resulting corrections to the Bekenstein-Hawking entropy. The near-horizon geometry AdS 2 ×S 2 (or other Riemann surface) preserves half of the supercharges in N = 2 supergravity with Fayet-Iliopoulos gauging. We derive a relation between the entropy and the black hole charges that suggests via AdS/CFT how subleading corrections contribute to the supersymmetric index in the dual microscopic picture. Depending on the model, the attractors are part of full black hole solutions with different asymptotics, such as Minkowski, AdS 4 , and hvLif 4 . We give explicit examples for each of the asymptotic cases and comment on the implications. Among other results, we find that the Weyl-squared terms spoil the exact two-derivative relation to non-BPS asymptotically flat black holes in ungauged supergravity.
We consider three dimensional N = 4 flat supergravity, with an abelian R-symmetry enhancing the g... more We consider three dimensional N = 4 flat supergravity, with an abelian R-symmetry enhancing the gravitational phase space. We obtain the field configuration whose asymptotic symmetries at null infinity coincide with the centrally extended N = 4 super Bondi-Metzner-Sachs (BMS) algebra. The killing spinors for this generic configuration are obtained together with the energy bounds imposed by supersymmetry. It is explicitly shown that the same algebra can be obtained as a flat (AdS radius → ∞ ) limit of the combined (2, 0) and (0, 2) sectors of AdS supergravity.
We study N = (2, 4, 8) supersymmetric extensions of the three dimensional BMS algebra (BMS 3 ) wi... more We study N = (2, 4, 8) supersymmetric extensions of the three dimensional BMS algebra (BMS 3 ) with most generic possible central extensions. We find that Nextended supersymmetric BMS 3 algebras can be derived by a suitable contraction of two copies of the extended superconformal algebras. Extended algebras from all the consistent contractions are obtained by scaling left-moving and right-moving supersymmetry generators symmetrically, while Virasoro and R-symmetry generators are scaled asymmetrically. On the way, we find that the BMS/GCA correspondence does not in general hold for supersymmetric systems. Using the β-γ and the b-c systems, we construct free field realisations of all the extended super-BMS 3 algebras.
We show the equality between macroscopic and microscopic (statistical) black hole entropy for a c... more We show the equality between macroscopic and microscopic (statistical) black hole entropy for a class of four dimensional non-supersymmetric black holes in N = 2 supergravity theory, up to the first subleading order in their charges. This solves a long standing entropy puzzle for this class of black holes. The macroscopic entropy has been computed in the presence of a newly derived higher-derivative supersymmetric invariant of [1], connected to the five dimensional supersymmetric Weyl squared Lagrangian. Microscopically, the crucial role in obtaining the equivalence is played by the anomalous gauge gravitational Chern-Simons term.
We classify all N = 2 rigid supersymmetric backgrounds in four dimensions with both Lorentzian an... more We classify all N = 2 rigid supersymmetric backgrounds in four dimensions with both Lorentzian and Euclidean signature that preserve eight real supercharges, up to discrete identifications. Among the backgrounds we find specific warpings of S 3 × R and AdS 3 × R, AdS 2 × S 2 and H 2 × S 2 with generic radii, and some more exotic geometries. We provide the generic two-derivative rigid vector and hypermultiplet actions and analyze the conditions imposed on the special Kähler and hyperkähler target spaces.
The question of the "physical meaning" and "origin" of the Bose-Einstein (BE)... more The question of the "physical meaning" and "origin" of the Bose-Einstein (BE) factor in the fluctuation-dissipation theorem (FDT) is often raised and this term is sometimes interpreted as originating from a real harmonic oscillator composition of the physical system. Such an interpretation, however, is not really founded. Inspired by the famous work of Caldeira and Leggett, we have been able
We discuss the fate of flat directions in higher derivative gravity by studying two explicit exam... more We discuss the fate of flat directions in higher derivative gravity by studying two explicit examples, namely higher derivative gauged supergravity in five dimensions and higher derivative type IIB string theory in ten dimensions. In the first case, the supersymmetric spinning black hole solution in asymptotically AdS spacetime, found by Gutowski and Reall, is analyzed. In this case we find that the flat direction at the two derivative level is not lifted after addition of higher derivative terms, and as it turns out, this result holds even for non-supersymmetric deformations of the higher derivative action. For the rotating D3-brane solutions in type IIB theory, the dilaton parametrizes a flat direction at leading order, but its fate changes upon including order (α ′ ) 3 supersymmetric higher derivative corrections to the type IIB action, i.e. its leading value gets fixed.
The conditions for fully supersymmetric backgrounds of general N = 2 locally supersymmetric theor... more The conditions for fully supersymmetric backgrounds of general N = 2 locally supersymmetric theories are derived based on the off-shell superconformal multiplet calculus. This enables the derivation of a non-renormalization theorem for a large class of supersymmetric invariants with higher-derivative couplings. The theorem implies that the invariant and its first order variation must vanish in a fully supersymmetric background. The conjectured relation of one particular higher-derivative invariant with a specific fivedimensional invariant containing the mixed gauge-gravitational Chern-Simons term is confirmed.
A new class of N = 2 locally supersymmetric higher-derivative invariants is constructed based on ... more A new class of N = 2 locally supersymmetric higher-derivative invariants is constructed based on logarithms of conformal primary chiral superfields. They characteristically involve a coupling to R µν 2 -1 3 R 2 , which equals the non-conformal part of the Gauss-Bonnet term. Upon combining one such invariant with the known supersymmetric version of the square of the Weyl tensor one obtains the supersymmetric extension of the Gauss-Bonnet term. The construction is carried out in the context of both conformal superspace and the superconformal multiplet calculus. The new class of supersymmetric invariants resolves two open questions. The first concerns the proper identification of the 4D supersymmetric invariants that arise from dimensional reduction of the 5D mixed gauge-gravitational Chern-Simons term. The second is why the pure Gauss-Bonnet term without supersymmetric completion has reproduced the correct result in calculations of the BPS black hole entropy in certain models.
The fluctuation-dissipation theorem (FDT) is very general and applies to a broad variety of diffe... more The fluctuation-dissipation theorem (FDT) is very general and applies to a broad variety of different physical phenomena in condensed matter physics. With the help of the FDT and following the famous work of Caldeira and Leggett, we show that, whenever linear response theory applies, any generic bosonic or fermionic system at finite temperature T can be mapped onto a fictitious system of free harmonic oscillators. To the best of our knowledge, this is the first time that such a mapping is explicitly worked out. This finding provides further theoretical support to the phenomenological harmonic oscillator models commonly used in condensed matter. Moreover, our result helps in clarifying an interpretation issue related to the presence and physical origin of the Bose-Einstein factor in the FDT.
We analyze BPS black hole attractors in the conformal 4d gauged supergravity formalism and apply ... more We analyze BPS black hole attractors in the conformal 4d gauged supergravity formalism and apply the technique known as supergravity localization in order to evaluate Sen’s quantum entropy function [1] in the AdS2×S2 near-horizon geometry. Under certain assumptions, we reduce the exact expression of the functional integral to a finite-dimensional integral for a number of supersymmetric black holes in gauged supergravity with AdS asymptotics subject to a holographic description via a dual field theory. Examples include the asymptotically AdS4×S7 Cacciatori-Klemm black holes [2] in M-theory and the asymptotically AdS5×S5 generalizations of Gutowski-Reall black holes [3] and Benini-Bobev black strings [4] in type IIB, as well as the recently constructed asymptotically AdS4×S6 solutions [5, 6] in massive type IIA. Our results provide an important first step towards a gravitational counterpart to the exact evaluation of supersymmetric partition functions at finite N for the holographical...
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