532 results on '"ZAFFARONI, ALBERTO"'
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2. Equivariant volume extremization and holography
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Colombo, Edoardo, Faedo, Federico, Martelli, Dario, and Zaffaroni, Alberto
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High Energy Physics - Theory ,Mathematical Physics ,Mathematics - Differential Geometry - Abstract
In a previous paper two of us (D.M. and A.Z.) proposed that a vast class of gravitational extremization problems in holography can be formulated in terms of the equivariant volume of the internal geometry, or of the cone over it. We substantiate this claim by analysing supergravity solutions corresponding to branes partially or totally wrapped on a four-dimensional orbifold, both in M-theory as well as in type II supergravities. We show that our approach recovers the relevant gravitational central charges/free energies of several known supergravity solutions and can be used to compute these also for solutions that are not known explicitly. Moreover, we demonstrate the validity of previously conjectured gravitational block formulas for M5 and D4 branes. In the case of M5 branes we make contact with a recent approach based on localization of equivariant forms, constructed with Killing spinor bilinears., Comment: 62 pages. v2: minor changes, subsection and appendix added, references added. v3: minor changes, published version
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- 2023
3. Equivariant localization and holography
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Martelli, Dario and Zaffaroni, Alberto
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High Energy Physics - Theory ,Mathematical Physics - Abstract
We discuss the theory of equivariant localization focussing on applications relevant for holography. We consider geometries comprising compact and non-compact toric orbifolds, as well as more general non-compact toric Calabi-Yau singularities. A key object in our constructions is the equivariant volume, for which we describe two methods of evaluation: the Berline-Vergne fixed-point formula and the Molien-Weyl formula, supplemented by the Jeffrey-Kirwan prescription. We present two applications in supersymmetric field theories. Firstly, we describe a method for integrating the anomaly polynomial of SCFTs on compact toric orbifolds. Secondly, we discuss equivariant orbifold indices that are expected to play a key role in the computation of supersymmetric partition functions. In the context of supergravity, we propose that the equivariant volume can be used to characterise universally the geometry of a large class of supersymmetric solutions. As an illustration, we employ equivariant localization to prove the factorization in gravitational blocks of various supergravity free energies, recovering previous results as well as obtaining generalizations., Comment: 69 pages, 10 figures; published version, few typos corrected
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- 2023
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4. The large $N$ limit of topologically twisted indices: a direct approach
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Hosseini, Seyed Morteza and Zaffaroni, Alberto
- Subjects
High Energy Physics - Theory - Abstract
We study the large $N$ limit of the refined topologically twisted index of three-dimensional $\mathcal{N} = 2$ gauge theories with a holographic dual, which is relevant for counting the number of microstates of rotating, magnetically charged and twisted AdS$_4$ black holes. As a difference with previous computations, we perform a direct saddle point analysis of the relevant matrix model. Among other things we explicitly identify the distribution of gauge magnetic fluxes that contributes at large $N$. The index exhibits a large $N$ factorized form in agreement with the supergravity expectations based on gravitational blocks and correctly reproduces the entropy of magnetically charged rotating AdS$_4 \times S^7$ black holes., Comment: 47 pages, 4 figures
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- 2022
5. The joy of factorization at large $N$: five-dimensional indices and AdS black holes
- Author
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Hosseini, Seyed Morteza, Yaakov, Itamar, and Zaffaroni, Alberto
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High Energy Physics - Theory - Abstract
We discuss the large $N$ factorization properties of five-dimensional supersymmetric partition functions for CFT with a holographic dual. We consider partition functions on manifolds of the form $\mathcal{M}= \mathcal{M}_3 \times S^2_\epsilon$, where $\epsilon$ is an equivariant parameter for rotation. We show that, when $\mathcal{M}_3$ is a squashed three-sphere, the large $N$ partition functions can be obtained by gluing elementary blocks associated with simple physical quantities. The same is true for various observables of the theories on $\mathcal{M}_3=\Sigma_\mathfrak{g} \times S^1$, where $\Sigma_\mathfrak{g}$ is a Riemann surface of genus $\mathfrak{g}$, and, with a natural assumption on the form of the saddle point, also for the partition function, corresponding to either the topologically twisted index or a mixed one. This generalizes results in three and four dimensions and correctly reproduces the entropy of known black objects in AdS$_6 \times_{w} S^4$ and AdS$_7\times S^4$. We also provide the supersymmetric background and explicitly perform localization for the mixed index on $\Sigma_\mathfrak{g} \times S^1 \times S^2_\epsilon$, filling a gap in the literature., Comment: 76 pages
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- 2021
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6. Equivariant localization and holography
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Martelli, Dario and Zaffaroni, Alberto
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- 2024
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7. Equivariant volume extremization and holography
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Colombo, Edoardo, Faedo, Federico, Martelli, Dario, and Zaffaroni, Alberto
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- 2024
- Full Text
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8. D-Branes for Gauge Theories
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Mekareeya, Noppadol, primary and Zaffaroni, Alberto, additional
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- 2023
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9. Rotating multi-charge spindles and their microstates
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Hosseini, Seyed Morteza, Hristov, Kiril, and Zaffaroni, Alberto
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High Energy Physics - Theory - Abstract
Some AdS$_3 \times M_7$ type IIB vacua have been recently proposed to arise from D3-branes wrapped on a spindle, a sphere with conical singularities at the poles. We explicitly construct a generalization of these solutions corresponding to a class of electrically charged and rotating supersymmetric black strings in AdS$_5 \times S^5$ with general magnetic fluxes on the spindle. We then perform a counting of their microstates using the charged Cardy formula. To this purpose, we derive the general form of the anomaly polynomial of the dual $\mathcal{N} = (0 , 2)$ CFT in two dimensions and we show that it can be obtained via a simple gluing procedure., Comment: 39 pages, v2: references added
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- 2021
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10. Universal AdS black holes in theories with sixteen supercharges and their microstates
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Hosseini, Seyed Morteza and Zaffaroni, Alberto
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High Energy Physics - Theory - Abstract
We provide a universal microscopic counting for the microstates of the asymptotically AdS black holes and black strings that arise as solutions of the half-maximal gauged supergravity in four and five dimensions. These solutions can be embedded in all M-theory and type II string backgrounds with an AdS vacuum and sixteen supercharges and provide an infinite set of examples dual to $\mathcal{N}=2$ and $\mathcal{N}=4$ conformal field theories in four and three dimensions, respectively. The counting is universal and it is performed by either studying the large $N$ limit of the relevant supersymmetric index of the dual field theory or by using the charged Cardy formula., Comment: 6 pages, v2: references added
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- 2020
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11. Anomalies, Black strings and the charged Cardy formula
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Hosseini, Seyed Morteza, Hristov, Kiril, Tachikawa, Yuji, and Zaffaroni, Alberto
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High Energy Physics - Theory - Abstract
We derive the general anomaly polynomial for a class of two-dimensional CFTs arising as twisted compactifications of a higher-dimensional theory on compact manifolds $\mathcal{M}_d$, including the contribution of the isometries of $\mathcal{M}_d$. We then use the result to perform a counting of microstates for electrically charged and rotating supersymmetric black strings in AdS$_5\times S^5$ and AdS$_7\times S^4$ with horizon topology BTZ$ \ltimes S^2$ and BTZ$ \ltimes S^2 \times \Sigma_\mathfrak{g}$, respectively, where $\Sigma_\mathfrak{g}$ is a Riemann surface. We explicitly construct the latter class of solutions by uplifting a class of four-dimensional rotating black holes. We provide a microscopic explanation of the entropy of such black holes by using a charged version of the Cardy formula., Comment: 42 pages, 1 figure; v2: crucial references added; v3: typos corrected
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- 2020
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12. Superconformal indices at large $N$ and the entropy of AdS$_5$ $\times$ SE$_5$ black holes
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Benini, Francesco, Colombo, Edoardo, Soltani, Saman, Zaffaroni, Alberto, and Zhang, Ziruo
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High Energy Physics - Theory ,General Relativity and Quantum Cosmology - Abstract
The large $N$ limit of the four-dimensional superconformal index was computed and successfully compared to the entropy of a class of AdS$_5$ black holes only in the particular case of equal angular momenta. Using the Bethe Ansatz formulation, we compute the index at large $N$ with arbitrary chemical potentials for all charges and angular momenta, for general $\mathcal{N}=1$ four-dimensional conformal theories with a holographic dual. We conjecture and bring some evidence that a particular universal contribution to the sum over Bethe vacua dominates the index at large $N$. For $\mathcal{N}=4$ SYM, this contribution correctly leads to the entropy of BPS Kerr-Newman black holes in AdS$_5 \times S^5$ for arbitrary values of the conserved charges, thus completing the microscopic derivation of their microstates. We also consider theories dual to AdS$_5 \times \mathrm{SE}_5$, where SE$_5$ is a Sasaki-Einstein manifold. We first check our results against the so-called universal black hole. We then explicitly construct the near-horizon geometry of BPS Kerr-Newman black holes in AdS$_5 \times T^{1,1}$, charged under the baryonic symmetry of the conifold theory and with equal angular momenta. We compute the entropy of these black holes using the attractor mechanism and find complete agreement with the field theory predictions., Comment: 36 pages + appendices; v2: typos corrected, references added
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- 2020
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13. Gluing gravitational blocks for AdS black holes
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Hosseini, Seyed Morteza, Hristov, Kiril, and Zaffaroni, Alberto
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High Energy Physics - Theory - Abstract
We provide a unifying entropy functional and an extremization principle for black holes and black strings in AdS$_4\times S^7$ and AdS$_5\times S^5$ with arbitrary rotation and generic electric and magnetic charges. This is done by gluing gravitational blocks, basic building blocks that are directly inspired by the holomorphic blocks appearing in the factorization of supersymmetric partition functions in three and four dimensions. We also provide an explicit realization of the attractor mechanism by identifying the values of the scalar fields at the horizon with the critical points of the entropy functional. We give examples based on dyonic rotating black holes with a twist in AdS$_4\times S^7$, rotating black strings in AdS$_5\times S^5$, dyonic Kerr-Newman black holes in AdS$_4\times S^7$ and Kerr-Newman black holes in AdS$_5\times S^5$. In particular, our entropy functional extends existing results by adding rotation to the twisted black holes in AdS$_4$ and by adding flavor magnetic charges for the Kerr-Newman black holes in AdS$_4$. We also discuss generalizations to higher-dimensional black objects., Comment: 44 pages, v2: Published version, (6.17) corrected; v3: typos corrected
- Published
- 2019
- Full Text
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14. Microstates of rotating AdS$_5$ strings
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Hosseini, Seyed Morteza, Hristov, Kiril, and Zaffaroni, Alberto
- Subjects
High Energy Physics - Theory - Abstract
We provide a general formula for the refined topologically twisted index of $\mathcal{N}=1$ gauge theories living on the world-volume of D3-branes at conical Calabi-Yau singularities in the Cardy limit. The index is defined as the partition function on $T^2 \times S^2_\omega$, with a partial topological twist and a $\Omega$-deformation along $S^2$, in the presence of background magnetic fluxes and fugacities for the global symmetries and can be used to study the properties of a class of BPS black strings. To this purpose, we find rotating domain-wall solutions of five-dimensional gauged supergravity interpolating between AdS$_5$ and a near horizon region consisting of a warped fibration of BTZ over a sphere. We explicitly construct rotating domain-walls that can be embedded in AdS$_5 \times S^5$ by uplifting a class of four-dimensional rotating black holes. We then provide a microscopic explanation of the entropy of such black holes by using the refined topologically twisted index of $\mathcal{N}=4$ super Yang-Mills., Comment: 31 pages; v2: typos corrected
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- 2019
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15. Geometry of $\mathcal{I}$-extremization and black holes microstates
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Hosseini, Seyed Morteza and Zaffaroni, Alberto
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High Energy Physics - Theory - Abstract
The entropy of a class of asymptotically AdS$_4$ magnetically charged BPS black holes can be obtained by extremizing the topologically twisted index of the dual three-dimensional field theory. This principle is known as $\mathcal{I}$-extremization. A gravitational dual of $\mathcal{I}$-extremization for a class of theories obtained by twisted compactifications of M2-branes living at a Calabi-Yau four-fold has been recently proposed. In this paper we investigate the relation between the two extremization principles. We show that the two extremization procedures are equivalent for theories without baryonic symmetries, which include ABJM and the theory dual to the non-toric Sasaki-Einstein manifold $V^{5,2}$. We then consider a class of quivers dual to M2-branes at toric Calabi-Yau four-folds for which the $\mathcal{I}$-functional can be computed in the large $N$ limit, and depends on three mesonic fluxes. We propose a gravitational dual for this construction, that we call mesonic twist, and we show that the gravitational extremization problem and $\mathcal{I}$-extremization are equivalent. We comment on more general cases., Comment: 55 pages
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- 2019
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16. Lectures on AdS Black Holes, Holography and Localization
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Zaffaroni, Alberto
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High Energy Physics - Theory - Abstract
In these lectures I review some recent progresses in counting the number of microstates of AdS supersymmetric black holes in dimensions equal or greater than four using holography. The counting is obtained by applying localization and matrix model techniques to the dual field theory. I cover in details the case of dyonic AdS$_4$ black holes, corresponding to a twisted compactification of the dual field theory, and I discuss the state of the art for rotating AdS$_5$ black holes., Comment: 83 pages, 2 figures; based on lectures given at CERN Winter School 2017 and ICTP School on Supersymmetric Localization, Holography and Related Topics 2018. v3: version to appear on Living Reviews in Relativity
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- 2019
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17. Proving the equivalence of $c$-extremization and its gravitational dual for all toric quivers
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Hosseini, Seyed Morteza and Zaffaroni, Alberto
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High Energy Physics - Theory - Abstract
The gravitational dual of $c$-extremization for a class of $(0,2)$ two-dimensional theories obtained by twisted compactifications of D3-brane gauge theories living at a toric Calabi-Yau three-fold has been recently proposed. The equivalence of this construction with $c$-extremization has been checked in various examples and holds also off-shell. In this note we prove that such equivalence holds for an arbitrary toric Calabi-Yau. We do it by generalizing the proof of the equivalence between $a$-maximization and volume minimization for four-dimensional toric quivers. By an explicit parameterization of the R-charges we map the trial right-moving central charge $c_r$ into the off-shell functional to be extremized in gravity. We also observe that the similar construction for M2-branes on $\mathbb{C}^4$ is equivalent to the $\mathcal{I}$-extremization principle that leads to the microscopic counting for the entropy of magnetically charged black holes in AdS$_4\times S^7$. Also this equivalence holds off-shell., Comment: 35 pages
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- 2019
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18. 6D attractors and black hole microstates
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Hosseini, Seyed Morteza, Hristov, Kiril, Passias, Achilleas, and Zaffaroni, Alberto
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High Energy Physics - Theory - Abstract
We find a family of AdS$_2\times \mathcal{M}_4$ supersymmetric solutions of the six-dimensional $\mathrm{F}(4)$ gauged supergravity coupled to one vector multiplet that arises as a low energy description of massive type IIA supergravity on (warped) AdS$_6\times S^4$. $\mathcal{M}_4$ is either a K\"ahler-Einstein manifold or a product of two Riemann surfaces with a constant curvature metric. These solutions correspond to the near-horizon region of a family of static magnetically charged black holes. In the case where $\mathcal{M}_4$ is a product of Riemann surfaces, we successfully compare their entropy to a microscopic counting based on the recently computed topologically twisted index of the five-dimensional $\mathcal{N}=1$ $\mathrm{USp}(2 N)$ theory with $N_f$ fundamental flavors and an antisymmetric matter field. Furthermore, our results suggest that the near-horizon regions exhibit an attractor mechanism for the scalars in the matter coupled $\mathrm{F}(4)$ gauged supergravity, and we give a proposal for it., Comment: 19 pages, v2: minor corrections
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- 2018
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19. Topologically twisted indices in five dimensions and holography
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Hosseini, Seyed Morteza, Yaakov, Itamar, and Zaffaroni, Alberto
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High Energy Physics - Theory - Abstract
We provide a formula for the partition function of five-dimensional $\mathcal{N}=1$ gauge theories on $\mathcal{M}_4 \times S^1$, topologically twisted along $\mathcal{M}_4$ in the presence of general background magnetic fluxes, where $\mathcal{M}_4$ is a toric K\"ahler manifold. The result can be expressed as a contour integral of the product of copies of the K-theoretic Nekrasov's partition function, summed over gauge magnetic fluxes. The formula generalizes to five dimensions the topologically twisted index of three- and four-dimensional field theories. We analyze the large $N$ limit of the partition function and some related quantities for two theories: $\mathcal{N}=2$ SYM and the $\mathrm{USp}(2N)$ theory with $N_f$ flavors and an antisymmetric matter field. For $\mathbb{P}^1 \times \mathbb{P}^1 \times S^1$, which can be easily generalized to $\Sigma_{\mathfrak{g}_2} \times \Sigma_{\mathfrak{g}_1} \times S^1$, we conjecture the form of the relevant saddle point at large $N$. The resulting partition function for $\mathcal{N}=2$ SYM scales as $N^3$ and is in perfect agreement with the holographic results for domain walls in AdS$_7 \times S^4$. The large $N$ partition function for the $\mathrm{USp}(2N)$ theory scales as $N^{5/2}$ and gives a prediction for the entropy of a class of magnetically charged black holes in massive type IIA supergravity., Comment: 80 pages. v3: minor corrections, published version
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- 2018
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20. A note on the entropy of rotating BPS AdS$_7\times S^4$ black holes
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Hosseini, Seyed Morteza, Hristov, Kiril, and Zaffaroni, Alberto
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High Energy Physics - Theory - Abstract
In this note we show that the entropy of BPS, rotating, electrically charged AdS$_7 \times S^4$ black holes can be obtained by an extremization principle involving a particular combination of anomaly coefficients of the six-dimensional $\mathcal{N} = (2, 0)$ theory. This result extends our previous finding for BPS, rotating AdS$_5 \times S^5$ black holes., Comment: 21 pages
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- 2018
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21. The large N limit of topologically twisted indices: a direct approach
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Hosseini, Seyed Morteza and Zaffaroni, Alberto
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- 2022
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22. A Universal Counting of Black Hole Microstates in AdS$_4$
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Azzurli, Francesco, Bobev, Nikolay, Crichigno, P. Marcos, Min, Vincent S., and Zaffaroni, Alberto
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High Energy Physics - Theory ,General Relativity and Quantum Cosmology - Abstract
Many three-dimensional $\mathcal{N}=2$ SCFTs admit a universal partial topological twist when placed on hyperbolic Riemann surfaces. We exploit this fact to derive a universal formula which relates the planar limit of the topologically twisted index of these SCFTs and their three-sphere partition function. We then utilize this to account for the entropy of a large class of supersymmetric asymptotically AdS$_4$ magnetically charged black holes in M-theory and massive type IIA string theory. In this context we also discuss novel AdS$_2$ solutions of eleven-dimensional supergravity which describe the near horizon region of large new families of supersymmetric black holes arising from M2-branes wrapping Riemann surfaces., Comment: 31 pages + appendices; v2: Added a discussion on the relation between black hole entropy and the on-shell action. Additional references
- Published
- 2017
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23. An extremization principle for the entropy of rotating BPS black holes in AdS$_5$
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Hosseini, Seyed Morteza, Hristov, Kiril, and Zaffaroni, Alberto
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High Energy Physics - Theory - Abstract
We show that the Bekenstein-Hawking entropy of a class of BPS electrically charged rotating black holes in AdS$_5\times S^5$ can be obtained by a simple extremization principle. We expect that this extremization corresponds to the attractor mechanism for BPS rotating black holes in five-dimensional gauged supergravity, which is still unknown. The expression to be extremized has a suggestive resemblance to anomaly polynomials and the supersymmetric Casimir energy recently studied for $\mathcal{N}=4$ super Yang-Mills., Comment: 27 pages; v2: refs added; v3: ref added
- Published
- 2017
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24. The Cardy limit of the topologically twisted index and black strings in AdS$_5$
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Hosseini, Seyed Morteza, Nedelin, Anton, and Zaffaroni, Alberto
- Subjects
High Energy Physics - Theory - Abstract
We evaluate the topologically twisted index of a general four-dimensional $\mathcal{N} = 1$ gauge theory in the "high-temperature" limit. The index is the partition function for $\mathcal{N} = 1$ theories on $S^2 \times T^2$, with a partial topological twist along $S^2$, in the presence of background magnetic fluxes and fugacities for the global symmetries. We show that the logarithm of the index is proportional to the conformal anomaly coefficient of the two-dimensional $\mathcal{N} = (0,2)$ SCFTs obtained from the compactification on $S^2$. We also present a universal formula for extracting the index from the four-dimensional conformal anomaly coefficient and its derivatives. We give examples based on theories whose holographic duals are black strings in type IIB backgrounds AdS$_5 \times \text{SE}_5$, where SE$_5$ are five-dimensional Sasaki-Einstein spaces., Comment: 31 pages, V2: minor corrections, refs added, V3: minor corrections, published version, V4: few signs corrected
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- 2016
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25. Exact microstate counting for dyonic black holes in AdS4
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Benini, Francesco, Hristov, Kiril, and Zaffaroni, Alberto
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High Energy Physics - Theory - Abstract
We present a counting of microstates of a class of dyonic BPS black holes in AdS$_4$ which precisely reproduces their Bekenstein-Hawking entropy. The counting is performed in the dual boundary description, that provides a non-perturbative definition of quantum gravity, in terms of a twisted and mass-deformed ABJM theory. We evaluate its twisted index and propose an extremization principle to extract the entropy, which reproduces the attractor mechanism in gauged supergravity., Comment: 4 pages
- Published
- 2016
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26. The moduli spaces of $3d$ ${\cal N} \ge 2$ Chern-Simons gauge theories and their Hilbert series
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Cremonesi, Stefano, Mekareeya, Noppadol, and Zaffaroni, Alberto
- Subjects
High Energy Physics - Theory - Abstract
We present a formula for the Hilbert series that counts gauge invariant chiral operators in a large class of 3d ${\cal N} \ge 2$ Yang-Mills-Chern-Simons theories. The formula counts 't Hooft monopole operators dressed by gauge invariants of a residual gauge theory of massless fields in the monopole background. We provide a general formula for the case of abelian theories, where nonperturbative corrections are absent, and consider a few examples of nonabelian theories where nonperturbative corrections are well understood. We also analyze in detail nonabelian ABJ(M) theories as well as worldvolume theories of M2-branes probing Calabi-Yau fourfold and hyperK\"ahler twofold singularities with ${\cal N} = 2$ and ${\cal N} = 3$ supersymmetry., Comment: 72 pages + appendices
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- 2016
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27. Supersymmetric partition functions on Riemann surfaces
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Benini, Francesco and Zaffaroni, Alberto
- Subjects
High Energy Physics - Theory ,Mathematical Physics ,Mathematics - Algebraic Geometry - Abstract
We present a compact formula for the supersymmetric partition function of 2d N=(2,2), 3d N=2 and 4d N=1 gauge theories on $\Sigma_g \times T^n$ with partial topological twist on $\Sigma_g$, where $\Sigma_g$ is a Riemann surface of arbitrary genus and $T^n$ is a torus with n=0,1,2, respectively. In 2d we also include certain local operator insertions, and in 3d we include Wilson line operator insertions along $S^1$. For genus g=1, the formula computes the Witten index. We present a few simple Abelian and non-Abelian examples, including new tests of non-perturbative dualities. We also show that the large N partition function of ABJM theory on $\Sigma_g \times S^1$ reproduces the Bekenstein-Hawking entropy of BPS black holes in AdS$_4$ whose horizon has $\Sigma_g$ topology., Comment: 34 pages, 1 figure
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- 2016
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28. Large $N$ matrix models for 3d ${\cal N}=2$ theories: twisted index, free energy and black holes
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Hosseini, Seyed Morteza and Zaffaroni, Alberto
- Subjects
High Energy Physics - Theory - Abstract
We provide general formulae for the topologically twisted index of a general three-dimensional ${\cal N}\geq 2$ gauge theory with an M-theory or massive type IIA dual in the large $N$ limit. The index is defined as the supersymmetric path integral of the theory on $S^2\times S^1$ in the presence of background magnetic fluxes for the R- and global symmetries and it is conjectured to reproduce the entropy of magnetically charged static BPS AdS$_4$ black holes. For a class of theories with an M-theory dual, we show that the logarithm of the index scales indeed as $N^{3/2}$ (and $N^{5/3}$ in the massive type IIA case). We find an intriguing relation with the (apparently unrelated) large $N$ limit of the partition function on $S^3$. We also provide a universal formula for extracting the index from the large $N$ partition function on $S^3$ and its derivatives and point out its analogy with the attractor mechanism for AdS black holes., Comment: 39 pages; v2: refs added; v3: typos removed
- Published
- 2016
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29. Holographic Effective Field Theories
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Martucci, Luca and Zaffaroni, Alberto
- Subjects
High Energy Physics - Theory - Abstract
We derive the four-dimensional low-energy effective field theory governing the moduli space of strongly coupled superconformal quiver gauge theories associated with D3-branes at Calabi-Yau conical singularities in the holographic regime of validity. We use the dual supergravity description provided by warped resolved conical geometries with mobile D3-branes. Information on the baryonic directions of the moduli space is also obtained by using wrapped Euclidean D3-branes. We illustrate our general results by discussing in detail their application to the Klebanov-Witten model., Comment: 56 pages; v2: minor changes, version published in JHEP
- Published
- 2016
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30. Nonlinear dynamics in asset pricing: the role of a sentiment index
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Campisi, Giovanni, Muzzioli, Silvia, and Zaffaroni, Alberto
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- 2021
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31. Extremal functions in AdS/CFT: black hole entropy, equivariant localization
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Colombo, E, ZAFFARONI, ALBERTO, COLOMBO, EDOARDO, Colombo, E, ZAFFARONI, ALBERTO, and COLOMBO, EDOARDO
- Abstract
In AdS/CFT si incontrano frequentemente problemi di estremizzazione. Osservabili in teoria di campo come cariche centrali e funzioni di partizione sulla sfera possono essere calcolati a partire da funzioni estremali delle soluzioni di supergravità duali. Queste ultime possono essere espresse in termini di quantità topologiche che appaiono naturalmente nel contesto della localizzazione equivariante. Un esempio particolarmente interessante di funzioni estremali sono le funzioni d'entropia di buchi neri supersimmetrici in AdS, la cui trasformata di Legendre riproduce l'entropia di Bekenstein-Hawking. Focalizzandoci sul caso di buchi neri di Kerr-Newman asintoticamente AdS_5 x SE_5, l'indice superconforme della duale teoria quiver N=1 eguaglia la funzione d'entropia nel limite di grande-N. Nella prima parte di questa tesi studiamo l'indice superconforme di teorie quiver N=1 a grande-N per valori generali di cariche elettriche e momenti angolari, usando sia la formulazione Bethe Ansatz che il più recente metodo di estensione ellittica. Siamo particolarmente interessati al caso di momenti angolari diversi, che è stato considerato solo parzialmente nella letteratura. Rivisitiamo il precedente calcolo con la formulazione Bethe Ansatz a momenti angolari generici e lo estendiamo in modo da includere una vasta classe di termini esponenziali in competizione. Nel mentre semplifichiamo anche la derivazione del risultato generale. Consideriamo anche il recente metodo di estensione ellittica; lo applichiamo al caso di momenti angolari diversi, trovando un buon accordo con i risultati di Bethe Ansatz. Investighiamo anche la relazione tra i due diversi approcci trovando in particolare che per ogni sella dell'azione ellittica ci sono termini corrispondenti nella formula Bethe Ansatz che a grande-N li eguagliano. Nella seconda parte di questa tesi studiamo le funzioni estremali di soluzioni in supergravità attraverso le lenti della localizzazione equivariante. Recentemente è stat, Extremization problems are frequently encountered in AdS/CFT. Field theory observables such as central charges and sphere partition functions can be computed from extremal functions of the dual supergravity solution. The latter can be expressed in terms of topological quantities that naturally arise in the context of equivariant localization. A particularly interesting example of extremal functions are the entropy functions of AdS supersymmetric black holes, whose Legendre transform reproduces the Bekenstein-Hawking entropy. Focusing on the case of Kerr-Newman black holes asymptotically AdS_5 x SE_5, the superconformal index of the dual four-dimensional N=1 quiver theory can match the entropy function in the large-N limit. In the first part of this thesis we study the superconformal index of N=1 quiver theories at large-N for general values of electric charges and angular momenta, using both the Bethe Ansatz formulation and the more recent elliptic extension method. We are particularly interested in the case of unequal angular momenta which has only been partially considered in the literature. We revisit the previous computation with the Bethe Ansatz formulation with generic angular momenta and extend it to encompass a large class of competing exponential terms. In the process, we also provide a simplified derivation of the original result. We consider the newly-developed elliptic extension method as well; we apply it to the case of unequal angular momenta, finding a good match with the Bethe Ansatz results. We also investigate the relation between the two different approaches, finding in particular that for every saddle of the elliptic action there are corresponding terms in the Bethe Ansatz formula that match it at large-N. In the second part of this thesis we study extremal functions of supergravity solutions through the lenses of equivariant localization. Recently it has been proposed that a vast class of gravitational extremization problems in holography can be
- Published
- 2024
32. Black hole microstates in AdS$_4$ from supersymmetric localization
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Benini, Francesco, Hristov, Kiril, and Zaffaroni, Alberto
- Subjects
High Energy Physics - Theory ,General Relativity and Quantum Cosmology - Abstract
This paper addresses a long standing problem, the counting of the microstates of supersymmetric asymptotically AdS black holes in terms of a holographically dual field theory. We focus on a class of asymptotically AdS$_4$ static black holes preserving two real supercharges which are dual to a topologically twisted deformation of the ABJM theory. We evaluate in the large $N$ limit the topologically twisted index of the ABJM theory and we show that it correctly reproduces the entropy of the AdS$_4$ black holes. An extremization of the index with respect to a set of chemical potentials is required. We interpret it as the selection of the exact R-symmetry of the superconformal quantum mechanics describing the horizon of the black hole., Comment: 35 pages + appendices, 4 figures; v2: refs added
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- 2015
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33. A topologically twisted index for three-dimensional supersymmetric theories
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Benini, Francesco and Zaffaroni, Alberto
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High Energy Physics - Theory ,Mathematics - Algebraic Geometry - Abstract
We provide a general formula for the partition function of three-dimensional $\mathcal{N}=2$ gauge theories placed on $S^2 \times S^1$ with a topological twist along $S^2$, which can be interpreted as an index for chiral states of the theories immersed in background magnetic fields. The result is expressed as a sum over magnetic fluxes of the residues of a meromorphic form which is a function of the scalar zero-modes. The partition function depends on a collection of background magnetic fluxes and fugacities for the global symmetries. We illustrate our formula in many examples of 3d Yang-Mills-Chern-Simons theories with matter, including Aharony and Giveon-Kutasov dualities. Finally, our formula generalizes to $\Omega$-backgrounds, as well as two-dimensional theories on $S^2$ and four-dimensional theories on $S^2 \times T^2$. In particular this provides an alternative way to compute genus-zero A-model topological amplitudes and Gromov-Witten invariants., Comment: 59 pages + appendices; v2: refs added; v3: minor corrections, published version
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- 2015
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34. T^{\sigma}_{\rho}(G) Theories and Their Hilbert Series
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Cremonesi, Stefano, Hanany, Amihay, Mekareeya, Noppadol, and Zaffaroni, Alberto
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High Energy Physics - Theory - Abstract
We give an explicit formula for the Higgs and Coulomb branch Hilbert series for the class of 3d N=4 superconformal gauge theories T^{\sigma}_{\rho}(G) corresponding to a set of D3 branes ending on NS5 and D5-branes, with or without O3 planes. Here G is a classical group, \sigma is a partition of G and \rho a partition of the dual group G^\vee. In deriving such a formula we make use of the recently discovered formula for the Hilbert series of the quantum Coulomb branch of N=4 superconformal theories. The result can be expressed in terms of a generalization of a class of symmetric functions, the Hall-Littlewood polynomials, and can be interpreted in mathematical language in terms of localization. We mainly consider the case G=SU(N) but some interesting results are also given for orthogonal and symplectic groups., Comment: 55 pages and a number of figures
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- 2014
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35. Coulomb branch Hilbert series and Three Dimensional Sicilian Theories
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Cremonesi, Stefano, Hanany, Amihay, Mekareeya, Noppadol, and Zaffaroni, Alberto
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High Energy Physics - Theory - Abstract
We evaluate the Coulomb branch Hilbert series of mirrors of three dimensional Sicilian theories, which arise from compactifying the $6d$ $(2,0)$ theory with symmetry $G$ on a circle times a Riemann surface with punctures. We obtain our result by gluing together the Hilbert series for building blocks $T_{\mathbf{\rho}}(G)$, where $\mathbf{\rho}$ is a certain partition related to the dual group of $G$, which we evaluated in a previous paper. The result is expressed in terms of a class of symmetric functions, the Hall-Littlewood polynomials. As expected from mirror symmetry, our results agree at genus zero with the superconformal index prediction for the Higgs branch Hilbert series of the Sicilian theories and extend it to higher genus. In the $A_1$ case at genus zero, we also evaluate the Coulomb branch Hilbert series of the Sicilian theory itself, showing that it only depends on the number of external legs., Comment: v1: 45 pages and 7 figures; v2: minor revision, version to appear in JHEP
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- 2014
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36. Coulomb branch Hilbert series and Hall-Littlewood polynomials
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Cremonesi, Stefano, Hanany, Amihay, Mekareeya, Noppadol, and Zaffaroni, Alberto
- Subjects
High Energy Physics - Theory - Abstract
There has been a recent progress in understanding the chiral ring of 3d $\mathcal{N}=4$ superconformal gauge theories by explicitly constructing an exact generating function (Hilbert series) counting BPS operators on the Coulomb branch. In this paper we introduce Coulomb branch Hilbert series in the presence of background magnetic charges for flavor symmetries, which are useful for computing the Hilbert series of more general theories through gluing techniques. We find a simple formula of the Hilbert series with background magnetic charges for $T_\rho(G)$ theories in terms of Hall-Littlewood polynomials. Here $G$ is a classical group and $\rho$ is a certain partition related to the dual group of $G$. The Hilbert series for vanishing background magnetic charges show that Coulomb branches of $T_\rho(G)$ theories are complete intersections. We also demonstrate that mirror symmetry maps background magnetic charges to baryonic charges., Comment: v1: 40 pages + appendices, 3 figures; v2: minor revision, version to appear in JHEP
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- 2014
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37. The joy of factorization at large N: five-dimensional indices and AdS black holes
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Hosseini, Seyed Morteza, Yaakov, Itamar, and Zaffaroni, Alberto
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- 2022
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38. Monopole operators and Hilbert series of Coulomb branches of 3d N = 4 gauge theories
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Cremonesi, Stefano, Hanany, Amihay, and Zaffaroni, Alberto
- Subjects
High Energy Physics - Theory - Abstract
This paper addresses a long standing problem - to identify the chiral ring and moduli space (i.e. as an algebraic variety) on the Coulomb branch of an N = 4 superconformal field theory in 2+1 dimensions. Previous techniques involved a computation of the metric on the moduli space and/or mirror symmetry. These methods are limited to sufficiently small moduli spaces, with enough symmetry, or to Higgs branches of sufficiently small gauge theories. We introduce a simple formula for the Hilbert series of the Coulomb branch, which applies to any good or ugly three-dimensional N = 4 gauge theory. The formula counts monopole operators which are dressed by classical operators, the Casimir invariants of the residual gauge group that is left unbroken by the magnetic flux. We apply our formula to several classes of gauge theories. Along the way we make various tests of mirror symmetry, successfully comparing the Hilbert series of the Coulomb branch with the Hilbert series of the Higgs branch of the mirror theory., Comment: 39 pages, one appendix; v2: JHEP format, 1+35 pages; v3: published version, 1+36 pages
- Published
- 2013
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39. Extended Supersymmetry on Curved Spaces
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Klare, Claudius and Zaffaroni, Alberto
- Subjects
High Energy Physics - Theory - Abstract
We study N=2 superconformal theories on Euclidean and Lorentzian four-manifolds with a view toward applications to holography and localization. The conditions for supersymmetry are equivalent to a set of differential constraints including a "generalised" conformal Killing spinor equation depending on various background fields. We solve these equations in the general case and give very explicit expressions for the auxiliary fields that we need to turn on to preserve some supersymmetry. As opposed to what has been observed for the N=1 case, the conditions for unbroken supersymmetry turn out to be almost independent of the signature of spacetime, with the exception of few degenerate cases including the topological twist. Generically, the only geometrical constraint coming from supersymmetry is the existence of a conformal Killing vector on the manifold, all other constraints determine the background auxiliary fields., Comment: 31 pages, v2: minor changes and important references added
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- 2013
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40. BPS Black Holes in AdS4 from M-theory
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Halmagyi, Nick, Petrini, Michela, and Zaffaroni, Alberto
- Subjects
High Energy Physics - Theory - Abstract
We study supersymmetric black holes in $AdS_4$ in the framework of four dimensional gauged $\N=2$ supergravity coupled to hypermultiplets. We derive the flow equations for a general electrically gauged theory where the gauge group is Abelian and, restricting them to the fixed points, we derive the gauged supergravity analogue of the attractor equations for theories coupled to hypermultiplets. The particular models we analyze are consistent truncations of M-theory on certain Sasaki-Einstein seven-manifolds. We study the space of horizon solutions of the form $AdS_2\times \Sigma_g$ with both electric and magnetic charges and find a four-dimensional solution space when the theory arises from a reduction on $Q^{111}$. For other $SE_7$ reductions, the solutions space is a subspace of this. We construct explicit examples of spherically symmetric black holes numerically., Comment: 38 page, 4 figures; typos corrected
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- 2013
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41. Supersymmetry on Three-dimensional Lorentzian Curved Spaces and Black Hole Holography
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Hristov, Kiril, Tomasiello, Alessandro, and Zaffaroni, Alberto
- Subjects
High Energy Physics - Theory - Abstract
We study N <= 2 superconformal and supersymmetric theories on Lorentzian threemanifolds with a view toward holographic applications, in particular to BPS black hole solutions. As in the Euclidean case, preserved supersymmetry for asymptotically locally AdS solutions implies the existence of a (charged) "conformal Killing spinor" on the boundary. We find that such spinors exist whenever there is a conformal Killing vector which is null or timelike. We match these results with expectations from supersymmetric four-dimensional asymptotically AdS black holes. In particular, BPS bulk solutions in global AdS are known to fall in two classes, depending on their graviphoton magnetic charge, and we reproduce this dichotomy from the boundary perspective. We finish by sketching a proposal to find the dual superconformal quantum mechanics on the horizon of the magnetic black holes., Comment: 40 pages, no figures; v2 typos corrected
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- 2013
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42. Non-Contact Estimation of Sleep Staging
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Zaffaroni, Alberto, Doheny, Emer P., Gahan, Luke, Ivanov, Yuri, Kilroy, Hannah, O’Mahony, Niall, O’Rourke, Damien, Magjarevic, Ratko, Editor-in-chief, Ładyżyński, Piotr, Series editor, Ibrahim, Fatimah, Series editor, Lacković, Igor, Series editor, Rock, Emilio Sacristan, Series editor, Eskola, Hannu, editor, Väisänen, Outi, editor, Viik, Jari, editor, and Hyttinen, Jari, editor
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- 2018
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43. Supersymmetry in Lorentzian Curved Spaces and Holography
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Cassani, Davide, Klare, Claudius, Martelli, Dario, Tomasiello, Alessandro, and Zaffaroni, Alberto
- Subjects
High Energy Physics - Theory - Abstract
We consider superconformal and supersymmetric field theories on four-dimensional Lorentzian curved space-times, and their five-dimensional holographic duals. As in the Euclidean signature case, preserved supersymmetry for a superconformal theory is equivalent to the existence of a charged conformal Killing spinor. Differently from the Euclidean case, we show that the existence of such spinors is equivalent to the existence of a null conformal Killing vector. For a supersymmetric field theory with an R-symmetry, this vector field is further restricted to be Killing. We demonstrate how these results agree with the existing classification of supersymmetric solutions of minimal gauged supergravity in five dimensions., Comment: 35 pages; v3: minor changes
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- 2012
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44. Supersymmetry on Curved Spaces and Holography
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Klare, Claudius, Tomasiello, Alessandro, and Zaffaroni, Alberto
- Subjects
High Energy Physics - Theory - Abstract
We study superconformal and supersymmetric theories on Euclidean four- and three-manifolds with a view toward holographic applications. Preserved supersymmetry for asymptotically locally AdS solutions implies the existence of a (charged) "conformal Killing spinor" on the boundary. We study the geometry behind the existence of such spinors. We show in particular that, in dimension four, they exist on any complex manifold. This implies that a superconformal theory has at least one supercharge on any such space, if we allow for a background field (in general complex) for the R-symmetry. We also show that this is actually true for any supersymmetric theory with an R-symmetry. We also analyze the three-dimensional case and provide examples of supersymmetric theories on Sasaki spaces., Comment: 27 pages; references added
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- 2012
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45. Non-supersymmetric CS-matter theories with known AdS duals
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Forcella, Davide and Zaffaroni, Alberto
- Subjects
High Energy Physics - Theory - Abstract
We consider three dimensional conformal field theories living on a stack of N anti-M2 branes at the tip of eight-dimensional supersymmetric cones. The corresponding supergravity solution is obtained by changing sign to the four-form in the Freund-Rubin solution representing M2 branes ("skew-whiffing" transformation) and it is known to be stable. The existence of these non supersymmetric, stable field theories, at least in the large N limit, is a peculiarity of the AdS4/CFT3 correspondence with respect to the usual AdS5/CFT4, and it is worthwhile to study it. We analyze in detail the KK spectrum of the skew-whiffed solution associated with S^7/Z_k and we speculate on the natural field content for a candidate non-supersymmetric dual field theory., Comment: 16 pages; Contribution prepared for the AHEP special issue on "Computational Algebraic Geometry in String and Gauge Theory", citations added
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- 2011
46. Non-Relativistic Solutions of N=2 Gauged Supergravity
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Halmagyi, Nick, Petrini, Michela, and Zaffaroni, Alberto
- Subjects
High Energy Physics - Theory - Abstract
We find infinite families of supersymmetric solutions of four dimensional, N=2 gauged supergravity with Lifshitz, Schrodinger and also AdS symmetries. We focus on the canonical example of a single hypermultiplet and a single vector multiplet and find that the spectrum of solutions depends crucially on whether the gaugings are electric or magnetic but to a far milder extent on the strength of the gaugings. For purely electric or purely magnetic gaugings we generically find Lifshitz solutions, while for a mixed gauging we find Schrodinger and AdS solutions. For some of the gaugings the theory has a known lift to string/M-theory thus giving a higher dimensional embedding of our solutions., Comment: 27 pages, v2 refs added, comments regarding string embeddings altered, cleaner discussion of the scaling parameter for Schrodinger solutions; v3 published version, refs added
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- 2011
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47. Parameter spaces of massive IIA solutions
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Tomasiello, Alessandro and Zaffaroni, Alberto
- Subjects
High Energy Physics - Theory - Abstract
We find a new class of N=2 massive IIA solutions whose internal spaces are S^2 fibrations over S^2 x S^2. These solutions appear naturally as massive deformations of the type IIA reduction of Sasaki-Einstein manifolds in M-theory, including Q^{1,1,1} and Y^{p,k}, and play a role in the AdS4/CFT3 correspondence. We use this example to initiate a systematic study of the parameter space of massive solutions with fluxes. We define and study the natural parameter space of the solutions, which is a certain dense subset of R^3, whose boundaries correspond to orbifold or conifold singularities. On a codimension-one subset of the parameter space, where the Romans mass vanishes, it is possible to perform a lift to M-theory; extending earlier work, we produce a family A^{p,q,r} of Sasaki-Einstein manifolds with cohomogeneity one and SU(2) x SU(2) x U(1) isometry. We also propose a Chern-Simons theory describing the duals of the massless and massive solutions., Comment: 35 pages, 5 figures; comments and references added
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- 2010
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48. Massive type IIA string theory cannot be strongly coupled
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Aharony, Ofer, Jafferis, Daniel, Tomasiello, Alessandro, and Zaffaroni, Alberto
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High Energy Physics - Theory - Abstract
Understanding the strong coupling limit of massive type IIA string theory is a longstanding problem. We argue that perhaps this problem does not exist; namely, there may be no strongly coupled solutions of the massive theory. We show explicitly that massive type IIA string theory can never be strongly coupled in a weakly curved region of space-time. We illustrate our general claim with two classes of massive solutions in AdS4xCP3: one, previously known, with N = 1 supersymmetry, and a new one with N = 2 supersymmetry. Both solutions are dual to d = 3 Chern-Simons-matter theories. In both these massive examples, as the rank N of the gauge group is increased, the dilaton initially increases in the same way as in the corresponding massless case; before it can reach the M-theory regime, however, it enters a second regime, in which the dilaton decreases even as N increases. In the N = 2 case, we find supersymmetry-preserving gauge-invariant monopole operators whose mass is independent of N. This predicts the existence of branes which stay light even when the dilaton decreases. We show that, on the gravity side, these states originate from D2-D0 bound states wrapping the vanishing two-cycle of a conifold singularity that develops at large N., Comment: 43 pages, 5 figures. v2: added references
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- 2010
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49. N=1 Chern-Simons theories, orientifolds and Spin(7) cones
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Forcella, Davide and Zaffaroni, Alberto
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High Energy Physics - Theory - Abstract
We construct three dimensional N=1 Chern-Simons theories living on M2 branes probing Spin(7) cones. We consider Spin(7) manifolds obtained as quotients of Calabi-Yau four-folds by an anti-holomorphic involution, following a construction by Joyce. The corresponding Chern-Simons theories can be obtained from N=2 theories by an orientifolding procedure. These theories are holographically dual to M theory solutions AdS_4 \times H, where the weak G_2 manifold H is the base of the Spin(7) cone., Comment: 26 pages, 3 figures, reference added.
- Published
- 2009
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50. New families of interpolating type IIB backgrounds
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Minasian, Ruben, Petrini, Michela, and Zaffaroni, Alberto
- Subjects
High Energy Physics - Theory - Abstract
We construct new families of interpolating two-parameter solutions of type IIB supergravity. These correspond to D3-D5 systems on non-compact six-dimensional manifolds which are T^2 fibrations over Eguchi-Hanson and multi-center Taub-NUT spaces, respectively. One end of the interpolation corresponds to a solution with only D5 branes and vanishing NS three-form flux. A topology changing transition occurs at the other end, where the internal space becomes a direct product of the four-dimensional surface and the two-torus and the complexified NS-RR three-form flux becomes imaginary self-dual. Depending on the choice of the connections on the torus fibre, the interpolating family has either N=2 or N=1 supersymmetry. In the N=2 case it can be shown that the solutions are regular., Comment: 20 pages
- Published
- 2009
- Full Text
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