12 research outputs found

    Dual versions of extended supergravities

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    Recently, using the model of N=2 supergravity -- vector multiplets interaction with the scalar field geometry SU(1,m)/SU(m)U(1)SU(1,m)/SU(m)\otimes U(1) as an example, we have shown that even when the scalar field geometry is fixed, one can have a whole family of the Lagrangians, which differ by vector field duality transformation. In this paper we carry out the construction of such families for the case of N=3 and N=4 supergravities, the scalar field geometry being SU(3,m)/SU(3)SU(m)U(1)SU(3,m)/SU(3)\otimes SU(m)\otimes U(1) and SU(1,1)/U(1)O(6,m)/O(6)O(m)SU(1,1)/U(1)\otimes O(6,m)/O(6)\otimes O(m), correspondingly. Moreover, it turns out that these families contain, as a partial case, the models describing the interaction of arbitrary number of vector multiplets with our hidden sectors, admitting spontaneous supersymmetry breaking without a cosmological term.Comment: 9 pages, plain LaTeX, no figure

    Axion gauge symmetries and generalized Chern-Simons terms in N=1 supersymmetric theories

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    We compute the form of the Lagrangian of N=1 supersymmetric theories with gauged axion symmetries. It turns out that there appear generalized Chern-Simons terms that were not considered in previous superspace formulations of general N=1 theories. Such gaugings appear in supergravities arising from flux compactifications of superstrings, as well as from Scherk-Schwarz generalized dimensional reduction in M-theory. We also present the dual superspace formulation where axion chiral multiplets are dualized into linear multiplets.Comment: References added and few misprints correcte

    N=2 Super-Higgs, N=1 Poincare' Vacua and Quaternionic Geometry

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    In the context of N=2 supergravity we explain the occurrence of partial super-Higgs with vanishing vacuum energy and moduli stabilization in a model suggested by superstring compactifications on type IIB orientifolds with 3-form fluxes. The gauging of axion symmetries of the quaternionic manifold, together with the use of degenerate symplectic sections for special geometry, are the essential ingredients of the construction.Comment: 18 page

    4-D gauged supergravity analysis of Type IIB vacua on K3×T2/Z2K3\times T^2/Z_2

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    We analyze N=2,1,0N=2,1,0 vacua of type IIB string theory on K3×T2/Z2K3\times T^2/Z_2 in presence of three-form fluxes from a four dimensional supergravity viewpoint. The quaternionic geometry of the K3K3 moduli space together with the special geometry of the NS and R-R dilatons and of the T2T^2-complex structure moduli play a crucial role in the analysis. The introduction of fluxes corresponds to a particular gauging of N=2, D=4 supergravity. Our results agree with a recent work of Tripathy and Trivedi. The present formulation shows the power of supergravity in the study of effective theories with broken supersymmetry.Comment: AMS-LaTeX, 29 page

    The minimal N=4 no-scale model from generalized dimensional reduction

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    We consider the generalized dimensional reduction of pure ungauged N=4, D=5 supergravity, where supersymmetry is spontaneously broken to N=2 or N=0 with identically vanishing scalar potential. We explicitly construct the resulting gauged D=4 theory coupled to a single vector multiplet, which provides the minimal N=4 realization of a no-scale model. We discuss its relation with the standard classification of N=4 gaugings, extensions to non-compact twists and to higher dimensions, the N=2 theories obtained via consistent Z_2 orbifold projections and prospects for further generalizations.Comment: 1+28 pages, no figures, JHEP3 LaTeX, published versio

    N=4 Supergravity Lagrangian for Type IIB Orientifold on T^6/Z_2 in Presence of Fluxes and D3-Branes

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    We derive the Lagrangian and the transformation laws of N=4 gauged supergravity coupled to matter multiplets whose sigma-model of the scalars is SU(1,1)/U(1)x SO(6,6+n)/SO(6)xSO(6+n) and which corresponds to the effective Lagrangian of the Type IIB string compactified on the T^6/Z_2 orientifold with fluxes turned on and in presence of n D3-branes. The gauge group is T^12 x G where G is the gauge group on the brane and T^12 is the gauge group on the bulk corresponding to the gauged translations of the R-R scalars coming from the R-R four--form. The N=4 bulk sector of this theory can be obtained as a truncation of the Scherk-Schwarz spontaneously broken N=8 supergravity. Consequently the full bulk spectrum satisfies quadratic and quartic mass sum rules, identical to those encountered in Scherk-Schwarz reduction gauging a flat group. This theory gives rise to a no scale supergravity extended with partial super-Higgs mechanism.Comment: 49 pages, LaTex, 2 figures. Misprints corrected, more comments adde

    Increasing the corrosion resistance of heat-resistant alloys for parts of power equipment

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    For the manufacture of parts and assemblies of the turbopump unit of details of power equipment, welded joints with corrosion resistant steels and heat-resistant alloys are used, requiring various modes heat treatment to achieve the required level of mechanical properties. In the manufacture of parts and assemblies of details of power equipment at the machine-building enterprises of Ukraine, it became necessary to replace semi-finished products. It is necessary to replace sheet products from high-alloy alloys ХН67МВТЮ and 06Х15Н6МВФБ with one alloy with a high complex of physical and mechanical characteristics. In the work, as a replacement for the applied heat-resistant alloys, Inconel 718 alloy welded to 316L steel. Samples of welded joints, processed according to the recommended mode, showed increased corrosion resistance.Для виготовлення деталей енергетичного обладнання застосовуються зварні з’єднання з корозійно-стійкими сталями та жароміцними сплавами, що потребують різних режимів термічної обробки для досягнення необхідного рівня механічних властивостей. При виготовленні деталей енергетичного обладнання на машинобудівних підприємствах України виникла потреба заміни напівфабрикатів. Необхідна заміна листового прокату з високолегованих сплавів ХН67МВТЮ та 06Х15Н6МВФБ на один сплав із високим комплексом фізико-механічних характеристик. У роботі в якості заміни жароміцних сплавів обраний сплав Inconel 718 у зварному з’єднанні зі сталлю 316L. Зразки зварних з’єднань, які оброблені за рекомендованим режимом, показали підвищену корозійну стійкість

    Anomalies, Anomalous U(1)'s and generalized Chern-Simons terms

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    A detailed analysis of anomalous U(1)'s and their effective couplings is performed both in field theory and string theory. It is motivated by the possible relevance of such couplings in particle physics, as well as a potential signal distinguishing string theory from other UV options. The most general anomaly related effective action is analyzed and parameterized. It contains Stuckelberg, axionic and Chern-Simons-like couplings. It is shown that such couplings are generically non-trivial in orientifold string vacua and are not in general fixed by anomalies. A similar analysis in quantum field theories provides similar couplings. The trilinear gauge boson couplings are also calculated and their phenomenological relevance is advocated. We do not find qualitative differences between string and field theory in this sector.Comment: 52 pages, 2 eps figures, LaTeX, feynmf & youngtab packages (v2 - Minor corrections, references added

    N=3 Warped Compactifications

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    Orientifolds with three-form flux provide some of the simplest string examples of warped compactification. In this paper we show that some models of this type have the unusual feature of D=4, N=3 spacetime supersymmetry. We discuss their construction and low energy physics. Although the local form of the moduli space is fully determined by supersymmetry, to find its global form requires a careful study of the BPS spectrum.Comment: 27 pages, v2: 32pp., RevTeX4, fixed factors, slightly improved sections 3D and 4B, v3: added referenc

    Holography of D-Brane Reconnection

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    Gukov, Martinec, Moore and Strominger found that the D1-D5-D5' system with the D5-D5' angle at 45 degrees admits a deformation "rho" preserving supersymmetry. Under this deformation, the D5-branes and D5'-branes reconnect along a single special Lagrangian manifold. We construct the near-horizon limit of this brane setup (for which no supergravity solution is currently known), imposing the requisite symmetries perturbatively in the deformation rho. Reducing to the three-dimensional effective gauged supergravity, we compute the scalar potential and verify the presence of a deformation with the expected properties. We compute the conformal dimensions as functions of rho. This spectrum naturally organizes into N=3 supermultiplets, corresponding to the 3/16 preserved by the brane system. We give some remarks on the symmetric orbifold CFT for Q_D5=Q_D5', outline the computation of rho-deformed correlators in this theory, and probe computations in our rho-deformed background.Comment: 33 pages, 5 figure
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