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We study global anomalies of discrete gauge symmetries in six-dimensional supergravities and their realizations in F-theory. We explicitly construct a discrete Green-Schwarz mechanism that depends on the choice of a coupling constant and on a certain quadratic refinement in differential cohomology. By geometrically engineering theories with G = ℤ3 gauge symmetry and no tensor multiplets, we observe that a particular choice of the quadratic refinement is singled out in F-theory. This implies new Swampland constraints on the discrete charge spectra of 6d supergravities. On the other hand, the discrete Green-Schwarz coupling depends on the geometry of the Calabi-Yau. We use anomaly inflow to relate this to a 't Hooft anomaly of the induced global symmetry in the worldsheet theories of non-critical strings. Using topological symmetry lines, we further relate this anomaly to the modular properties of twisted-twined elliptic genera. We then argue that the latter are encoded in the A-model topological string partition functions on different torus fibrations that are equipped with a flat torsional B-field. This allows us to derive a geometric expression for the global discrete anomaly in terms of the height-pairing of a multi-section on a genus one fibered Calabi-Yau. [ABSTRACT FROM AUTHOR]

We test the gauge/gravity duality between the matrix model and type IIA string theory at low temperatures with unprecedented accuracy. To this end, we perform lattice Monte Carlo simulations of the Berenstein-Maldacena-Nastase (BMN) matrix model, which is the one-parameter deformation of the Banks-Fischler-Shenker-Susskind (BFSS) matrix model, taking both the large N and continuum limits. We leverage the fact that sufficiently small flux parameters in the BMN matrix model have a negligible impact on the energy of the system while stabilizing the flat directions so that simulations at smaller N than in the BFSS matrix model are possible. Hence, we can perform a precision measurement of the large N continuum energy at the lowest temperatures to date. The energy is in perfect agreement with supergravity predictions including estimations of α′-corrections from previous simulations. At the lowest temperature where we can simulate efficiently (T = 0.25λ1/3, where λ is the 't Hooft coupling), the difference in energy to the pure supergravity prediction is less than 10%. Furthermore, we can extract the coefficient of the 1/N4 corrections at a fixed temperature with good accuracy, which was previously unknown. [ABSTRACT FROM AUTHOR]

As a continuation of our previous papers arXiv:2109.07639 and arXiv:2202.08196, we study the linearized structure of the manifestly 4D, N = 2 supersymmetric theory of the cubic couplings of the higher spin gauge superfields to the matter hypermultiplets. We consider in detail the superfield equations of motion, construct the conserved hypermultiplet superfield currents, explore their component structure (basically in the bosonic sector) and compare it with the corresponding currents in the conventional higher-spin bosonic theory. We thoroughly study the N = 2 spin 2 and 3 models as instructive examples. [ABSTRACT FROM AUTHOR]

We calculate the logarithmic correction to the entropy of asymptotically flat and AdS black holes (rotating, non-rotating, charged, and uncharged) embedded in Einstein-Maxwell-dilaton (EMD) theories with U(1)-charged. The leading quantum gravitational corrections are achieved in both extremal and non-extremal limits of black hole temperature by designing a common Euclidean gravity setup that evaluates the "logarithmic term" from one-loop effective actions via heat kernel method-based calculations. EMD theories are universal building blocks of compactified string theory or supergravity models in 4D. For a concrete example, we generalize the entire setup and calculate logarithmic corrections for black holes in U(1)2-charged EMD models intersecting with N = 4 ungauged and gauged bosonic supergravity. In contrast to flat backgrounds, all the AdS4 results are found to be non-topological, providing a wider "infrared window" into the microscopic degrees of freedom of black holes in string theory. [ABSTRACT FROM AUTHOR]

We study holographic aspects of 2D dilaton-supergravity in flat space-time using gauge theoretic BF formulation. The asymptotic symmetries in Bondi gauge and at finite temperature span a supersymmetric extension of the warped Virasoro algebra at level zero. The boundary action is determined such that the bulk variational principle is ensured and turns out to be a super-warped Schwarzian theory at the vanishing level. We also study the thermodynamics of the black hole saddle in this model. [ABSTRACT FROM AUTHOR]

We propose additional tests of holography by studying supersymmetric Wilson loops in p+1-dimensional maximally supersymmetric Yang–Mills (SYM) theories on the lattice in the large N limit. In the dual gravity description, this computation involves calculating the area of a fundamental string worldsheet in certain Type II supergravity backgrounds. Though thermodynamic observables have been computed on the lattice using Monte Carlo methods and agree with the supergravity results in various dimensions, not much has been done for the gauge-invariant operators such as the Wilson loop. We provide analytical predictions for these loops for various non-conformal Dp-brane background cases with p ≤ 2 in the large N limit and comment on how these can be computed on non-orthogonal lattices in various models. [ABSTRACT FROM AUTHOR]

Introduction/purpose: Supersymmetry is a symmetry of the Lagrangian that goes beyond Lie groups. It allows the exchange of bosons and fermions. The most important model is the Minimal Supersymmetric Standard Model, or MSSM. Methods: Supercharge algebra, superfields, Grassmann numbers, Berezin integral. Results: Supersymmetric transformations are global, they do not depend on spacetime coordinates. In the case of Supergravity, they are local. Conclusion: Supersymmetric models, and MSSM in particular, could describe more physics and more particles beyond the Standard Model. [ABSTRACT FROM AUTHOR]

We consider a double scaling limit of the plane wave matrix model (PWMM), in which the gravity dual geometry of PWMM reduces to a class of spherical NS5-brane solutions. We identify the form of the scaling limit for the dual geometry of PWMM around a general vacuum and then translate the limit into field-theoretic language. We also show that the limit indeed exists at least in a certain planar quarter-BPS sector of PWMM by using the localization computation analytically. In addition, we employ the hybrid Monte Carlo method to compute the matrix integral obtained by the localization method, near the parameter region where the supergravity approximation is valid. Our numerical results, which are considered to be the first computation of a quantum loop correction to the Lin–Maldacena geometry, suggest that the double scaling limit exists beyond the planar sector. [ABSTRACT FROM AUTHOR]

Herein, we report that the influence of annealing time on the microstructure and mechanical properties of Al-14.5Si alloys solidified under a super-gravity field. The results indicate that the coarsening of metastable eutectic Si and formation of precipitated Si could be observed at the early stage of annealing. A slight increase in yield strength and tensile strength could be observed in the sample annealed for 0.25 h, which can be ascribed to the formation of precipitated Si with limited size during the early stage of annealing. The intensified diffusion of Si atoms during annealing led to the coarsening and coalescence of the eutectic Si, as well as the coarsening of precipitated Si with further extension of the annealing time. [ABSTRACT FROM AUTHOR]

In a vacuum environment, large and near-net-shaped 2060 Al–Li alloy tubes were fabricated by centrifugal casting for the first time, and a heat-flow simulation model was established to study process parameters and the solidification behavior. The microstructure and mechanical properties of the alloy were investigated. It was found that in the forming range, the texture was gradually dominated by fine and homogeneous equiaxed grains (average grain size = ∼64 μm) with the decrease in pouring temperature, and segregation decreased because solute particles moved in orientation for less time under the physical field. The tensile strength of the T8 state reached 541 MPa under the process parameters of pouring temperature = 680 °C and rotational speed = 900 r/min. With the increase in rotational speed, the filling capacity was improved and shrinkage defects were reduced; thus, the alloy exhibited excellent strength. The tensile strength of the T8 state reached 516 MPa under the process parameters of pouring temperature = 760 °C and rotational speed = 1000 r/min.

We extend the Cecotti–Kallosh model of Starobinsky inflation in supergravity by adding a holomorphic function to the superpotential in order to generate a large peak in the power spectrum of scalar (curvature) perturbations. In our approach, the singular non-canonical kinetic terms are largely responsible for inflation (as an attractor solution), whereas the superpotential is engineered to generate a production of PBH. We study the cases with (a) a linear holomorphic function, (b) a quadratic holomorphic function, and (c) an exponential holomorphic function, as regards the dependence of inflation and PBH production upon parameters of those functions and initial conditions, as well as verify viability of inflation with our superpotentials. We find that an efficient production of PBH consistent with cosmic microwave background measurements is only possible in the second (b) case. We calculate the masses of the produced PBH and find that they are below the Hawking (black hole) evaporation limit, so that they cannot be part of the current dark matter in our Universe. [ABSTRACT FROM AUTHOR]

In consideration of the characteristics of supergravity to strengthen solidification structures, the effect of the supergravity field (SGF) on the grain refinement and mechanical properties of Cu-0.5Sn alloys was investigated in this paper. Firstly, it was experimentally verified that the addition of Sn could effectively refine the grain. Subsequently, the variations in grain size, tensile strength, and plasticity of the Cu-0.5Sn alloy were compared in normal and SGF conditions. The results revealed that the tensile strength and plasticity of the alloy increased with the increase in gravity coefficient. The ultimate tensile strength of the Cu-0.5Sn alloy in a normal gravity field was 145.2 MPa, while it was 160.2, 165.3, 167.9, and 182.0 MPa in an SGF with G = 100, 300, 500, and 1000, respectively, and there was almost no effect on conductivity. Finally, it was clarified that the mechanism of grain refinement by SGF was that the intense convection caused the fracture of the dendrites to become new nucleating particles. The increased viscosity under SGF hindered the diffusion of atoms in the melt and slowed down the movement of atoms toward the nucleus, leading to a decrease in grain size. [ABSTRACT FROM AUTHOR]

We revisit the work by Volkov and Soroka on spontaneously broken local supersymmetry. It is demonstrated for the first time that, for specially chosen parameters of the theory, the Volkov–Soroka action is invariant under two different local supersymmetries. One of them is present for arbitrary values of the parameters and acts on the Goldstino, while the other supersymmetry emerges only in a special case and leaves the Goldstino invariant. The former can be used to gauge away the Goldstino, and then the resulting action coincides with that proposed by Deser and Zumino for consistent supergravity in the first-order formalism. In this sense, pure N=1 supergravity is a special case of the Volkov–Soroka theory, although it was not discovered by these authors. We also explain how the Volkov–Soroka approach allows one to naturally arrive at the 1.5 formalism. Our analysis provides a nonlinear realization approach to construct unbroken N=1 Poincaré supergravity. [ABSTRACT FROM AUTHOR]

We investigate inflationary models in f (R , T) modified gravity with a kinetic coupling term ω 2 G μ ν ∂ μ ϕ ∂ ν ϕ having a positive factor needed to remove the ghosts. Taking f (R , T) = R + 2 β T , we calculate and analyze the relevant observable quantities including the spectral index n s and the tensor-to-scalar ratio r using the slow-roll approximations. Concretely, we consider two scenarios described by the decoupling and the coupling behaviors between the scalar potential and the f (R , T) gravity via the moduli space by dealing with two potentials being the quartic one V (ϕ) = λ ϕ 4 and the small field inflation V (ϕ) = V 0 (1 − (ϕ μ) α). For the quartic inflation model, we consider a decoupling behavior. For the small field inflation, however, we present the parameter decoupling and coupling scenarios. For both scenarios, we compute and inspect n s and r showing interesting results. For three different values of the number of e-folds N = 6 0 , 6 5 and 70, we find that the coupling between f (R , T) and the scalar potential via the moduli space provides an excellent agreement with the observational findings. In the last part of this work, we provide a possible discussion on the amplitude of the scalar power spectrum needed to provide a viability of the proposed theory. Considering the second potential form in the parameter coupling scenario, we find acceptable values in certain points of the moduli space. [ABSTRACT FROM AUTHOR]

Warm inflation, its different particle physics model implementations, and the implications of dissipative particle production for its cosmology are reviewed. First, we briefly present the background dynamics of warm inflation and contrast it with the cold inflation picture. An exposition of the space of parameters for different well-motivated potentials, which are ruled out, or severely constrained in the cold inflation scenario, but not necessarily in warm inflation, is provided. Next, the quantum field theory aspects in realizing explicit microscopic models for warm inflation are given. This includes the derivation of dissipation coefficients relevant in warm inflation for different particle field theory models. The dynamics of cosmological perturbations in warm inflation are then described. The general expression for the curvature scalar power spectrum is shown. We then discuss in detail the relevant regimes of warm inflation, the weak and strong dissipative regimes. We also discuss the results predicted in these regimes of warm inflation and how they are confronted with the observational data. We explain how the dissipative dynamics in warm inflation can address several long-standing issues related to (post-) inflationary cosmology. This includes recent discussions concerning the so-called swampland criteria and how warm inflation can belong to the landscape of string theory. [ABSTRACT FROM AUTHOR]

The removing of suspended dross in galvanized zinc is the key point to obtain defect free coatings and inhibit the generation of solid wastes including surface and bottom dross which are detrimental to preserving environment. A supergravity technology was used to induce the galvanized zinc liquid to be purifying through ceramic foam filter (Al 2 O 3 CFF). Al-Fe intermetallic were the dominant inclusions and precipitated in the galvanized zinc liquid as suspended dross. During the processing of purifying galvanized zinc liquid, inclusions were intercepted on the surface of Al 2 O 3 CFF as residue by the way of being wrapped in oxide film, and some fine inclusions were captured in the filter. The removal ratio of Fe (R Fe), loss percentage of Al (L Al) and the yield of zinc (Y Zn) respectively reached 76%, 63% and 96% at T = 450 °C and G= 50 through the Al 2 O 3 CFF with pore size of 170 ppi and thickness of 20 mm. According to the exploratory experiment on the purification, a continuous purification was further performed for completing engineering scale purification of galvanized zinc liquid. R Fe of 73% and L Al of 59% were obtained after the process of continuously purifying 8 kg molten galvanized zinc. [Display omitted] [ABSTRACT FROM AUTHOR]

We use the counterterms subtraction method to calculate various thermodynamical quantities for charged rotating black holes in five-dimensional minimal gauged supergravity (Chong et al. in Phys Rev Lett 95:161301, 2005, https://doi.org/10.1103/PhysRevLett.95.161301, arXiv:hep-th/0506029). Specifically, we analyze certain issues related to the first law and Smarr's relation in the presence of a conformal anomaly. Among the bulk quantities calculated are the on-shell action, total mass, and angular momenta of the solution. All these quantities are consistent with previous calculations made using other methods. For the boundary theory, we calculate the renormalized stress tensor, conformal anomaly, and Casimir energy. Using the Papadimitriou–Skenderis analysis (Papadimitriou and Skenderis in J High Energy Phys 08:004, 2005), we show that the mass calculated via the counterterms method satisfies the first law of black hole thermodynamics. To discuss extended thermodynamics, we extend the definition of the thermodynamic volume to cases with conformal anomalies using a procedure similar to that of Papadimitriou–Skenderis. We show that this volume correctly accounts for extra terms due to boundary metric variation. This shows that the mass and volume calculated using counterterms satisfy Smarr's relation as well as the first law. [ABSTRACT FROM AUTHOR]

We perform the maximal twist of eleven-dimensional supergravity. This twist is partially topological and exists on manifolds of G 2 × S U (2) holonomy. Our derivation starts with an explicit description of the Batalin–Vilkovisky complex associated to the three-form multiplet in the pure spinor superfield formalism. We then determine the L ∞ module structure of the supersymmetry algebra on the component fields. We twist the theory by modifying the differential of the Batalin–Vilkovisky complex to incorporate the action of a scalar supercharge. We find that the resulting free twisted theory is given by the tensor product of the de Rham and Dolbeault complexes of the respective G 2 and SU(2) holonomy manifolds as conjectured by Costello. [ABSTRACT FROM AUTHOR]

We explore type II supersymmetric double field theory in superspace. The double supervielbein is an element of the orthosymplectic group OSp(10, 10|64), which also governs the structure of generalized superdiffeomorphisms. Unlike bosonic double field theory, the local tangent space must be enhanced from the double Lorentz group in order to eliminate unphysical components of the supervielbein and to define covariant torsion and curvature tensors. This leads to an infinite hierarchy of local tangent space symmetries, which are connected to the super-Maxwell∞ algebra. A novel feature of type II is the Ramond-Ramond sector, which can be encoded as an orthosymplectic spinor (encoding the complex of super p-forms in conventional superspace). Its covariant field strength bispinor itself appears as a piece of the supervielbein. We provide a concise discussion of the superspace Bianchi identities through dimension two and show how to recover the component supersymmetry transformations of type II DFT. In addition, we show how the democratic formulation of type II superspace may be recovered by gauge-fixing. [ABSTRACT FROM AUTHOR]

A reheating phase in the early universe is an essential part of all inflationary models during which not only the Standard Model (SM) quanta are produced but it can also shed light on the production of dark matter. In this work, we explore a class of reheating models where the reheating is induced by a cubic interaction of the inflaton ϕ to the SM Higgs boson h of the form ghϕMPlϕ|h|2 adopting the α-attractor T-model of inflation. Assuming inflaton as a background field such interaction implies a ϕ-dependent mass term of the Higgs boson and a non-trivial phase-space suppression of the reheating efficiency. As a consequence, the reheating is prolonged and the maximal temperature of the SM thermal bath is reduced. In particular, due to oscillations of the inflaton field the ϕ-dependent Higgs boson mass results in periodic transitions between phases of broken and unbroken electroweak gauge symmetry. The consequences of these rapid phase transitions have been studied in detail. A purely gravitational reheating mechanism in the presence of the inflaton background, i.e., for ghϕ = 0, has also been investigated. It turned out that even though it may account for the total production of SM radiation in the absence of ghϕ, its contribution to the reheating is subdominant for the range of ghϕ considered in this work. Approximate analytical solutions of Boltzmann equations for energy densities of the inflaton and SM radiation have been obtained. As a dark matter candidate a massive Abelian vector boson, Xμ, has been considered. Various production mechanisms of Xμ have been discussed including (i) purely gravitational production from the inflaton background, (ii) gravitational freeze-in from the SM quanta, (iii) inflaton decay through a dim-5 effective operator, and (iv) Higgs portal freeze-in and Higgs decay through a dim-6 effective operator. Parameters that properly describe the observed relic abundance have been determined. [ABSTRACT FROM AUTHOR]

We construct a new family of AdS2× S2× S2 solutions to Type IIA supergravity with 4 supercharges acting with non-Abelian T-duality on the recent class constructed in [1]. We focus on a particular solution in this class asymptoting locally to an AdS5 Gaiotto-Maldacena geometry. This solution allows for a line defect interpretation within the 4d N = 2 SCFT dual to this geometry, that we study in detail. We show that the defect branes, consisting on a non-trivial intersection of D2-D4-NS5-F1 branes, can be interpreted as baryon vertices within the 4d N = 2 SCFT, whose backreaction gives rise to the AdS2 solution. We construct the explicit quiver quantum mechanics that flows in the IR to the dual SCQM, and show that it can be embedded within the quiver CFT associated to the AdS5 solution. The quiver quantum mechanics arises from a brane box set-up of D2-branes stretched between perpendicular NS5-branes, that we construct from the AdS2 solution. We provide non-trivial checks of our proposed duality. Our construction provides one further example of the successful applications of non-Abelian T-duality to holography, in this case in providing a very non-trivial connection between AdS2 solutions, line defects and brane boxes. [ABSTRACT FROM AUTHOR]

In this paper we use the superconformal approach to derive the higher derivative action for 풩 = 3 Poincaré supergravity in four space-time dimensions. We first study the coupling of 풩 = 3 vector multiplets to conformal supergravity. Thereafter we combine it with the pure 풩 = 3 conformal supergravity action and use a minimum of three vector multiplets as compensators to arrive at Poincaré supergravity with higher derivative corrections. We give a general prescription on how to eliminate the auxiliary fields in an iterative manner and obtain the supergravity action order by order in derivatives. We also show that the truncation of the action at fourth order in derivatives is a consistent truncation. [ABSTRACT FROM AUTHOR]

In 26 + 1 space–time dimensions, we introduce a gravity theory whose massless spectrum can be acted upon by the Monster group when reduced to 25 + 1 dimensions. This theory generalizes M-theory in many respects, and we name it Monstrous M-theory, or M 2 -theory. Upon Kaluza–Klein reduction to 25 + 1 dimensions, the M 2 -theory spectrum irreducibly splits as 1 ⊕ 196,883, where 1 is identified with the dilaton, and 196,883 is the dimension of the smallest non-trivial representation of the Monster. This provides a field theory explanation of the lowest instance of the Monstrous Moonshine, and it clarifies the definition of the Monster as the automorphism group of the Griess algebra by showing that such an algebra is not merely a sum of unrelated spaces, but descends from massless states for M 2 -theory, which includes Horowitz and Susskind's bosonic M-theory as a subsector. Further evidence is provided by the decomposition of the coefficients of the partition function of Witten's extremal Monster SCFT in terms of representations of S O 24 , the massless little group in 25 + 1 ; the purely bosonic nature of the involved S O 24 -representations may be traced back to the unique feature of 24 dimensions, which allow for a non-trivial generalization of the triality holding in 8 dimensions. Last but not least, a certain subsector of M 2 -theory, when coupled to a Rarita–Schwinger massless field in 26 + 1 , exhibits the same number of bosonic and fermionic degrees of freedom; we cannot help but conjecture the existence of a would-be N = 1 supergravity theory in 26 + 1 space–time dimensions. [ABSTRACT FROM AUTHOR]

We explore the swampland conjectures of quintessence and tachyon scalar field models in f (T) and Einstein gravities, respectively. In f (T) gravity, we consider cold and warm (by assuming generalized dissipative coefficient) inflationary scenarios and develop constraints on de-Sitter conjectures through Bekenstein entropy relation. In usual inflation, the de-Sitter conjecture constraint becomes constant (in terms of models constant parameters) which can be easily analyzed for its validity (i.e., | V ′ | V ≤ O (1)). However, in warm inflation, we analyze the de-Sitter conjecture constraint through τ ′ V τ V ′ , i.e., if τ ′ V τ V ′ < 1 then | V ′ | V ≤ O (1) and hence we can obtain the required result. For evaluating this condition, we choose three well-known potentials such as monomial chaotic, hilltop and generalized exponential. It is observed that the condition τ ′ V τ V ′ < 1 satisfied for all three potentials in both regimes of dissipative coefficient for specific choice of constants. We also obtain satisfactory results of de-Sitter conjecture for tachyon and polytropic (with quintessence scalar field) in general relativity. We investigate the consistency of assumed potentials through inflationary parameters n s and r comparing with Planck's observational data 2018 and found them compatible with the recent observations. [ABSTRACT FROM AUTHOR]

We present non- and ultra-relativistic Jackiw–Teitelboim (JT) supergravity as metric BF theories based on the extended Newton–Hooke and extended AdS Carroll superalgebras in two spacetime dimensions, respectively. The extended Newton–Hooke structure, and, in particular, the invariant metric necessary for the BF construction of non-relativistic JT supergravity, is obtained by performing an expansion of the N = 2 AdS 2 superalgebra. Subsequently, we introduce the extended AdS 2 Carroll superalgebra, and the associated invariant metric, as a suitable redefinition of the extended Newton–Hooke superalgebra. The mapping involved can be seen as the supersymmetric extension of the duality existing at the purely bosonic level between the extended Newton–Hooke algebra with (positive) negative cosmological constant and the extended (A)dS Carroll algebra in two dimensions. Finally, we provide the Carrollian JT supergravity action in the BF formalism. Moreover, we show that both the non-relativistic and the ultra-relativistic theories presented can also be obtained by direct expansion of N = 2 JT supergravity. [ABSTRACT FROM AUTHOR]

The Ni-based superalloy is used as the turbine blade, which is subject to the coupling effect of temperature and super-gravity during service. As the Ni-based superalloys are difficult to become homogenous after using the solid solution heat treatment, a study on morphology and composition distribution of Ni-base superalloys with segregation during microstructural degradation is necessary. This study investigates the microstructure of the ex-service turbine blade and cast samples subjected to the high-temperature centrifugal test. The difference in the size and shape factor of the γ′ phase decreased with the stress caused by the super-gravity condition, indicating a higher magnitude of homogenization degree. The higher stress will also promote the merge of the sub-grain boundaries, leading to a lower density and higher orientational deviation of the sub-grain boundaries. [ABSTRACT FROM AUTHOR]

In this work, we propose and investigate an inflationary model with a kinetic coupling term κ G μ ν ∂ μ ϕ ∂ ν ϕ and a combined scalar potential V (ϕ) = α ϕ 2 V 0 + arctan (β ϕ) V 0 . Exploiting the dynamical system analysis, we identify the stationary points and examine their stability showing certain restrictions on the involved parameters α , β and p = κ V 0 . Then, we compute and study the relevant observable quantities such as the spectral index n s and the tensor-to-scalar ratio r from slow-roll approximations. For certain values of the restricted parameters, we find that n s and r are in a good agreement with the current observation data. To support such findings, we consider the limit corresponding to the vanishing kinetic coupling contribution. We find that this limit provides a boomerang-like geometry intersecting almost all Planck contours associated with the (n s − r) curves. [ABSTRACT FROM AUTHOR]

We study the 3-point functions of gauge-invariant scalar operators in four dimensional N = 2 superconformal quiver theories using supersymmetric localization in the planar limit of a large number of colors. By exploiting a web of nontrivial relations, we show that the 3-point functions can be expressed in terms of the 2-point functions through exact Ward-like identities that are valid for all values of the coupling constant. In this way, using recent results about the 2-point functions, we are able to obtain the asymptotic strong-coupling expansion of the 3-point functions and of the corresponding structure constants in the planar limit. Our results extend to sub-leading orders what has been recently found at leading order, where a precise match with calculations within the AdS/CFT correspondence at the supergravity level is possible. Therefore, our findings can be interpreted also as a prediction for the sub-leading string corrections to these holographic calculations. [ABSTRACT FROM AUTHOR]

In Bakhmatov et al. (Phys. Rev. D 105(8): L081904, 2022) we presented a modification of 11-dimensional supergravity field equations which upon dimensional reduction yields generalized supergravity equations in 10-dimensions. In this paper we provide full technical details of that result which is based on SL(5) exceptional field theory. The equations are obtained by making a non-unimodular tri-vector Yang-Baxter deformation which breaks the initial local diffeomorphism symmetry in 11 dimensions down to separate coordinate transformations in external 7 and internal 4 directions. We also give some non-trivial solutions to these equations. [ABSTRACT FROM AUTHOR]

In this paper we study four concrete models, based on no-scale supergravity with SU(2,1)/SU(2) × U(1) symmetry. We modify either the Kähler potential or the superpotential, which are related to the no-scale theory with this symmetry. In this scenario, the induced Gravitational Waves, are calculated to be detectable by the future space-based observations such as LISA, BBO and DECIGO. The models under study are interrelated, as they all yield the Starobinsky effective-like scalar potential in the unmodified case. We evaluate numerically the scalar power spectrum and the stochastic background of the Gravitational Waves, satisfying the observational Planck cosmological constraints for inflation. [ABSTRACT FROM AUTHOR]

Recently, the purification technology for high-purity aluminum (Al) has become the focus and difficulty of the majority of researchers. In this study, a novel approach for removing iron (Fe) impurities from pure Al via combining the supergravity field and semi-solid refining was proposed. Various separation temperatures (T), holding times (th), and separation times (ts) were applied within a gravitational field to explore their impact on the purification process and its underlying mechanisms. The optimal conditions were achieved at T = 653 °C, th = 40 min, ts = 3 min, and a gravity coefficient G = 1000, with the loss rate of purified Al reaching up to 4.1% and the removal rate of Fe reaching 81.9%. The Fe content in pure Al was reduced from 0.32 wt.% to 0.06 wt.%. Moreover, the purified mechanism of supergravity in a semi-solid method was reported for the first time. It was concluded that supergravity could decrease the value of the effective distribution coefficient (ke), thereby promoting the continuous migration of Fe impurities at the solidification interface into the liquid phase. The Fe-rich phase in the Al melt was completely filtered to the lower part of the crucible in the supergravity field, completing the further purification of the pure Al.

In this paper, minimal supersymmetric AdS3 solutions on G2‐orientifolds of type IIA and IIB supergravity are studied. These are obtained by techniques of the bispinor formalism. A straightforward argument is derived against AdS3 solutions in massless type IIA string theory on such G2‐backgrounds. Furthermore, it is shown that some of the AdS3 solutions in massive type IIA do admit a separation of scales, whereas the same cannot be said for the type IIB vacua. Finally, a formula for the 3d superpotential in the bispinor language is given that is valid for both type IIA and type IIB configurations. It is shown that the supersymmetry conditions of this superpotential lead back to the bispinor equations. [ABSTRACT FROM AUTHOR]

We analyze conditions for a tri-vector deformation of a supergravity background to preserve some supersymmetry. Working in the formalism of the SL(5) exceptional field theory, we present its supersymmetry transformations and introduce an additional USp(4) transformation to stay in the supergravity frame. This transformation acts on local indices and deforms BPS equations of exceptional field theory. The requirement for the deformation to vanish is the desired condition. The condition is shown to be consistent with previous results on bi-vector deformations. [ABSTRACT FROM AUTHOR]

In this work, we study the inflationary cosmology in modified gravity theory f (R , T) = R + 2 λ T (λ is the modified gravity parameter) with three distinct classes of inflation potentials (i) ϕ p e − α ϕ , (ii) (1 − ϕ p) e − α ϕ and (iii) α ϕ 2 1 + α ϕ 2 where α , p are the potential parameters. We have derived the Einstein equation, potential slow-roll parameters, the scalar spectral index n s , tensor-to-scalar ratio r and tensor spectral index n T in modified gravity theory. We obtain the range of λ using the spectral index constraints in the parameter space of the potentials. Comparing our results with PLANCK 2018 data and WMAP data, we found out the modified gravity parameter λ lies between − 0. 3 7 < λ < 1. 4 8 3. [ABSTRACT FROM AUTHOR]

We study the vacuum structures of four-dimen-sional N = 1 old minimal supergravity with higher derivative corrections. We find that N = 1 supergravity with Riemann curvature square corrections and higher derivative matter chiral multiplets induces a non-trivial de Sitter vacuum, even in the absence of superpotentials. This vacuum generically breaks supersymmetry. We show that the auxiliary fields in the gravity and the chiral multiples play important roles to generate a potential in supersymmetric higher derivative theories. [ABSTRACT FROM AUTHOR]

We classify all warped dS 5 backgrounds in D  = 11 supergravity with enhanced supersymmetry. We show that backgrounds preserving N  = 16 supersymmetries consist of either a stack of M5 branes with transverse space R 5 , or a generalized M5-brane configuration with transverse space R × N 4 , where N 4 is a hyper-Kähler manifold and the M5-brane harmonic function is determined by a hyper-Kähler potential on N 4. Moreover, we find that there are no backgrounds preserving exactly N  = 24 supersymmetries. Backgrounds preserving N  = 32 supersymmetries correspond to either R 1 , 10 or A d S 7 × S 4 . [ABSTRACT FROM AUTHOR]

Starting with Witten's twistor string, chiral string theories have emerged that describe field theory amplitudes without the towers of massive states of conventional strings. These models are known as ambitwistor strings due to their target space; the space of complexified null geodesics, also called ambitwistor space. Correlators in these string theories directly yield compact formulæ for tree-level amplitudes and loop integrands, in the form of worldsheet integrals fully localized on solutions to constraints known as the scattering equations. In this chapter, we discuss two incarnations of the ambitwistor string: a 'vector representation' starting in space–time and structurally resembling the Ramond Neveu–Schwarz (RNS) superstring, and a four-dimensional twistorial version closely related to, but distinct from Witten's original model. The RNS-like models exist for several theories, with 'heterotic' and type II models describing super-Yang–Mills and 10d supergravities respectively, and they manifest the double copy relations directly at the level of the worldsheet models. In the second half of the chapter, we explain how the underlying models lead to diverse applications, ranging from extensions to new sectors of theories, loop amplitudes and to scattering on curved backgrounds. We conclude with a brief discussion of connections to conventional strings and celestial holography. [ABSTRACT FROM AUTHOR]

The post-Minkowskian expansion of Einstein's general theory of relativity has received much attention in recent years due to the possibility of harnessing the computational power of modern amplitude calculations in such a classical context. In this brief review, we focus on the post-Minkowskian expansion as applied to the two-body problem in general relativity without spin, and we describe how relativistic quantum field theory can be used to greatly simplify analytical calculations based on the Einstein–Hilbert action. Subtleties related to the extraction of classical physics from such quantum mechanical calculations highlight the care which must be taken when both positive and negative powers of Planck's constant are at play. In the process of obtaining classical results in both Einstein gravity and supergravity, one learns new aspects of quantum field theory that are obscured when using units in which Planck's constant is set to unity. The scattering amplitude approach provides a self-contained framework for deriving the two-body scattering valid in all regimes of energy. There is hope that the full impact of amplitude computations in this field may significantly alter the way in which gravitational wave predictions will advance in the coming years. [ABSTRACT FROM AUTHOR]

It is well-known that gravitino propagation in standard supergravities is free of any causality problems. However, two issues related to gravitino propagation were recently uncovered in specific supergravities with nonlinear supersymmetry. One of them concerns potential acausality/superluminality, whereas the second one arises from the vanishing of the sound speed at specific points during inflation. The former is famously related to positivity constraints on specific EFT operators, derived from dispersion relations on the energy-growing part of scattering amplitudes, and indeed we show that subluminality constraints for the gravitino are related via the equivalence theorem to positivity bounds in low-energy goldstino actions. However, the former are stronger, in the sense that they apply to functions of the scalar fields not only in the ground state, but for any field values such as those scanned by time-dependent solutions, unlike bounds derived from 2 → 2 scattering amplitudes in the vacuum. We also argue that nontrivial causality constraints arise only in the case where nonlinear supersymmetry in the matter sector is encoded into superfield constraints which do not seem to arise from microscopic two-derivative lagrangians, in particular for the orthogonal constraint used to build minimal models of inflation in supergravity. This allows us to propose simple alternatives which maintain the minimality of the spectra and are causal in all points of the theory parameter space. We also discuss minimal supergravity models of inflation along these lines. [ABSTRACT FROM AUTHOR]

We study graviton scattering on AdS4× S7, which is dual to the stress tensor multiplet four-point function in the maximally supersymmetric 3d U(N)1× U(N)−1 ABJM theory. We compute 1-loop corrections to this holographic correlator coming from Witten diagrams with supergravity R and higher derivative R4 vertices, up to contact term ambiguities, and find that the flat space limit matches the corresponding terms in the 11d M-theory S-matrix. We then use supersymmetric localization to show that all the 1-loop contact terms vanish, as was previously observed for the AdS4× S7/ℤ2 theory dual to U(N)2× U(N)−2 ABJM. Finally, we use the recent localization results of Gaiotto and Abajian, as inspired by twisted M-theory, to compute all the short OPE coefficients in correlators of the stress tensor multiplet and the next lowest half-BPS operator, which we find saturate the bootstrap bounds on these mixed correlators for all N. [ABSTRACT FROM AUTHOR]

The long dissolution time and large dispensed volumes of oil repellent polymers in offshore oil fields lead to a great increase in the volume and number of dissolution and maturation tanks in the polymer formulation system. However, there is limited space and load-bearing capacity at the offshore platform and only a small space is available for the dispensing system. To further optimize the polymer dispensing system and reduce its floor space, the super-gravity technology may be considered as a way to speed up the dissolution of the polymer. The mechanism of super-gravity rapid dissolution was investigated by establishing mathematical models and with indoor experiments. The effects of filler pore size and super-gravity factor on polymer dissolution time and solution viscosity were investigated using the super-gravity rapid dissolution device, then combined with established graded forced stretching devices for field magnification experiments. The results indicated that the super-gravity method can substantially shorten the polymer dissolution time. The basic dissolution time of the polymer AP-P4 was shortened by 35 min compared with the conventional formulation method after use of the super-gravity rapid dissolution device. The optimal process conditions for the preparation of polymer solution by the super-gravity rapid dissolution device were selected as the optimal super-gravity factor range of 1031~1298. [ABSTRACT FROM AUTHOR]

Extra-terrestrial explorations require electrochemical energy storage devices able to operate in gravity conditions different from those of planet earth. In this context, lithium (Li)-based batteries have not been fully investigated, especially cell formation and cycling performances under supergravity (i.e., gravity > 9.8 m s−2) conditions. To shed some light on these aspects, here, we investigate the behavior of non-aqueous Li metal cells under supergravity conditions. The physicochemical and electrochemical characterizations reveal that, distinctly from earth gravity conditions, smooth and dense Li metal depositions are obtained under supergravity during Li metal deposition on a Cu substrate. Moreover, supergravity allows the formation of an inorganic-rich solid electrolyte interphase (SEI) due to the strong interactions between Li+ and salt anions, which promote significant decomposition of the anions on the negative electrode surface. Tests in full Li metal pouch cell configuration (using LiNi0.8Co0.1Mn0.1O2-based positive electrode and LiFSI-based electrolyte solution) also demonstrate the favorable effect of the supergravity in terms of deposition morphology and SEI composition and ability to carry out 200 cycles at 2 C (400 mA g−1) rate with a capacity retention of 96%. The behavior of lithium metal batteries at various gravity levels is not yet clearly understood. Here, the authors demonstrate the beneficial effect of supergravity in terms of battery performance improvement and favorable solid electrolyte interphase formation. [ABSTRACT FROM AUTHOR]

Non-gauge generated exact solutions of simple supergravity field equations that describe pp-waves in Rosen coordinates are presented in the language of complex quaternion valued exterior differential forms. [ABSTRACT FROM AUTHOR]