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We revisit the Emergence Proposal in the vector multiplet moduli space of type IIA N = 2 supersymmetric string vacua in four dimensions, for which the string tree-level prepotential and the string one-loop correction are exactly known via mirror symmetry. We argue that there exists an exact notion of emergence, according to which these four-dimensional couplings can be computed exactly in any asymptotic limit in field space. In such limits, a perturbative quantum gravity theory emerges, whose fundamental degrees of freedom include all complete infinite towers of states with typical mass scale not larger than the species scale. For a decompactification limit, this picture is closely related to and in fact motivated by the computation of Gopakumar-Vafa invariants. In addition, in the same limit our results suggest that the emergent theory will also contain asymptotically tensionless wrapped NS5-branes. [ABSTRACT FROM AUTHOR]

It has recently been shown that the leading Wilson coefficient in type II string theory can take (almost) all values allowed by unitarity, crossing symmetry and maximal supersymmetry in D = 10 and D = 9 dimensions. This suggests that string theory might define the unique consistent quantum theory of gravity with maximal supersymmetry. We study the minima of the leading Wilson coefficient in D = 6, 7 and 8 dimensions and find the global minimum at the point in moduli space with maximal symmetry. The minimum value turns out to always be negative for D ≤ 7. [ABSTRACT FROM AUTHOR]

We study the quantum dynamics of a system of n Abelian N = 1 vector multiplets coupled to 1 2 n n + 1 chiral multiplets which parametrise the Hermitian symmetric space Sp(2n, ℝ)/U(n). In the presence of supergravity, this model is super-Weyl invariant and possesses the maximal non-compact duality group Sp(2n, ℝ) at the classical level. These symmetries should be respected by the logarithmically divergent term (the "induced action") of the effective action obtained by integrating out the vector multiplets. In computing the effective action, one has to deal with non-minimal operators for which the known heat kernel techniques are not directly applicable, even in flat (super)space. In this paper we develop a method to compute the induced action in Minkowski superspace. The induced action is derived in closed form and has a simple structure. It is a higher-derivative superconformal sigma model on Sp(2n, ℝ)/U(n). The obtained N = 1 results are generalised to the case of N = 2 local supersymmetry: a system of n Abelian N = 2 vector multiplets coupled to N = 2 chiral multiplets XI parametrising Sp(2n, ℝ)/U(n). The induced action is shown to be proportional to ∫ d 4 x d 4 θ d 4 θ ¯ E K X X ¯ , where K X X ¯ is the Kähler potential for Sp(2n, ℝ)/U(n). We also apply our method to compute DeWitt's a2 coefficients in some non-supersymmetric theories with non-minimal operators. [ABSTRACT FROM AUTHOR]

We propose quantum gravitational constraints on effective four-dimensional theories with N = 1 supersymmetry. These Swampland constraints arise by demanding consistency of the worldsheet theory of a class of axionic, or EFT, strings whose existence follows from the Completeness Conjecture of quantum gravity. Modulo certain assumptions, we derive positivity bounds and quantization conditions for the axionic couplings to the gauge and gravitational sector at the two- and four-derivative level, respectively. We furthermore obtain general bounds on the rank of the gauge sector in terms of the gravitational couplings to the axions. We exemplify how these bounds rule out otherwise consistent effective supergravity theories as theories of quantum gravity. Our derivations of the quantum gravity bounds are tested and further motivated in concrete string theoretic settings. In particular, this leads to a sharper version of the bound on the gauge group rank in F-theory on elliptic four-folds with a smooth base, which improves the known geometrical Kodaira bounds. We furthermore provide a detailed derivation of the EFT string constraints in heterotic string compactifications including higher derivative corrections to the effective action and apply the bounds to M-theory compactifications on G2 manifolds. [ABSTRACT FROM AUTHOR]

The ℤ 2 × ℤ 2 heterotic string orbifold yielded a large space of phenomenological three generation models and serves as a testing ground to explore how the Standard Model of particle physics may be incorporated in a theory of quantum gravity. In this paper, we explore the existence of type 0 models in this class of string compactifications. We demonstrate the existence of type 0 ℤ 2 × ℤ 2 heterotic string orbifolds, and show that there exist a large degree of redundancy in the space of GGSO projection coefficients when the type 0 restrictions are implemented. We explore the existence of such configurations in several constructions. The first correspond to essentially a unique configuration out of a priori 2 2 1 discrete GGSO choices. We demonstrate this uniqueness analytically, as well as by the corresponding analysis of the partition function. A wider classification is performed in S ̃ -models and S -models, where the first class correspond to compactifications of a tachyonic ten-dimensional heterotic string vacuum, whereas the second correspond to compactifications of the ten-dimensional nontachyonic S O (1 6) × S O (1 6). We show that the type 0 models in both cases contain physical tachyons at the free fermionic point in the moduli space. These vacua are therefore necessarily unstable, but may be instrumental in exploring the string dynamics in cosmological scenarios. We analyze the properties of the string one-loop amplitude. Naturally, these are divergent due to the existence of tachyonic states. We show that once the tachyonic states are removed by hand the amplitudes are finite and exhibit a form of misaligned supersymmetry. [ABSTRACT FROM AUTHOR]

In this paper, we study a class of symmetry reduced models of N = 1 super- gravity using self-dual variables. It is based on a particular Ansatz for the gravitino field as proposed by D'Eath et al. We show that the essential part of the constraint algebra in the classical theory closes. In particular, the (graded) Poisson bracket between the left and right supersymmetry constraint reproduces the Hamiltonian constraint. For the quantum theory, we apply techniques from the manifestly supersymmetric approach to loop quantum supergravity, which yields a graded analog of the holonomy-flux algebra and a natural state space. We implement the remaining constraints in the quantum theory. For a certain subclass of these models, we show explicitly that the (graded) commutator of the supersymmetry constraints exactly reproduces the classical Poisson relations. In particular, the trace of the commutator of left and right supersymmetry constraints reproduces the Hamilton constraint operator. Finally, we consider the dynamics of the theory and compare it to a quantization using standard variables and standard minisuperspace techniques. [ABSTRACT FROM AUTHOR]

We show that the rotating black hole solutions bring new effects in the particle physics, allowing to unite gravity with quantum theory. Due to extremely large spin/mass ratio (for typical spinning particles), the rotating Kerr black hole solution deforms space topologically on the Compton scale, which increases extremely effective influence gravity on quantum processes, and gravity starts to collaborate with quantum processes, instead of confront them. In particular, Kerr's gravity defines several important structures and parameters of electron, in particular, its non-perturbative shape, the associated Wilson loop, features of the used supersymmetry and specials of the stringy system. [ABSTRACT FROM AUTHOR]

We initiate the classification of supersymmetric solutions of type II supergravity on R 1 , 2 × S 3 × M 4 . We find explicit local expressions for all backgrounds with either a single Killing spinor or two of equal norm, up to PDE's. We show that the only type II AdS × 4 S 3 solution is the known N = 4 AdS 4 background obtained from the near-horizon limit of intersecting D2–D6 branes. Various known branes and intersecting brane systems are recovered, and we obtain a novel class of R 1 , 2 × S 2 × S 3 solutions in IIA. [ABSTRACT FROM AUTHOR]

We study the constraints of spacetime supersymmetry for perturbative three- and two-dimensional Minkowski vacua of the critical heterotic string. Assuming a standard RNS construction of the spacetime supersymmetry generators and a compact unitary internal superconformal worldsheet theory, we describe the worldsheet structures associated to various spacetime supersymmetries. In three dimensions we show that there are no CFT surprises: each allowed spacetime supersymmetry is realized by a supergravity compactification. As a recent orbifold construction shows, in two dimensions there are more exotic possibilities, and we discuss how these fit into our analysis. [ABSTRACT FROM AUTHOR]

Quantum M-theory is formulated using the current algebra technique. The current algebra is based on a Kac-Moody algebra rather than usual finite dimensional Lie algebra. Specifically, I study the Kac-Moody algebra that was shown recently to contain all the ingredients of M-theory. Both the internal symmetry and the external Lorentz symmetry can be realized inside , so that, by constructing the current algebra of , I obtain both internal gauge theory and gravity theory. The energy-momentum tensor is constructed as the bilinear form of the currents, yielding a system of quantum equations of motion of the currents/fields. Supersymmetry is incorporated in a natural way. The so-called 'field-current identity' is built in and, for example, the gravitino field is itself a conserved supercurrent. One unanticipated outcome is that the quantum gravity equation is not identical to the one obtained from the Einstein-Hilbert action. [ABSTRACT FROM AUTHOR]

I discuss the role of quantum effects in the phenomenology of effective supergravity theories from compactification of the weakly coupled heterotic string. An accurate incorporation of these effects requires a regularization procedure that respects local supersymmetry and BRST invariance and that retains information associated with the cut-off scale, which has physical meaning in an effective theory. I briefly outline the Pauli–Villars regularization procedure, describe some applications, and comment on what remains to be done to fully define the effective quantum field theory. [ABSTRACT FROM AUTHOR]

We study the inclusive production of a Higgs boson in association with a high- p photon at the LHC, detailing the leading-order features of the main processes contributing to the Hγ final state. Requiring an extra hard photon in Higgs production upsets the cross-section hierarchy for the dominant channels. The Hγ inclusive production comes mainly from photons radiated in vector-boson fusion (VBF), which accounts for about 2/3 of the total rate, for p > 30 GeV, at leading order. On the other hand, radiating a high- p photon in the main top-loop Higgs channel implies an extra parton in the final state, which suppresses the production rate by a further α power. As a result, the Hγ production via top loops at the LHC has rates comparable with the ones arising from either the $$ Ht\overline{t} $$ production or the HW ( Z)γ associated production. Then, in order of decreasing cross section, comes the single-top-plus-Higgs channel, followed in turn by the heavy-flavor fusion processes $$ b\overline{b}\to H\gamma $$ and $$ c\overline{c}\to H\gamma $$. The Hγ production via electroweak loops has just a minor role. At larger c.m. energies, the $$ Ht\overline{t}\gamma $$ channel surpasses the total contribution of top-loop processes. In particular, requiring p > 30 GeV at $$ \sqrt{S}\simeq 100 $$ TeV, $$ Ht\overline{t}\gamma $$ accounts for about 1 /4 of the inclusive Hγ production at leading order, about half of the total being due to VBF production. [ABSTRACT FROM AUTHOR]

This work considers an extension of the Standard Model (SM) Higgs sector by a real, scalar singlet field, including applicability to a dark matter (DM) model with the addition of a Yukawa coupling to a fermionic dark matter candidate. The collider signatures and constraints on the mixed two-Higgs scenario are determined, including limits from Higgs production signals and exclusion searches, as well as constraints arising from the Higgs total and invisible widths. As there is overwhelming Higgs data which is consistent with a SM scenario, the case in which an additional scalar has evaded detection is further explored in the context of Higgs precision measurement. The discovery reach and prospective signatures of the model at a proposed linear collider are investigated, with particular focus on the Higgs triple coupling, and di-Higgs production processes. [ABSTRACT FROM AUTHOR]

We present a version of the twin Higgs mechanism with vector-like top partners. In this setup all gauge anomalies automatically cancel, even without twin leptons. The matter content of the most minimal twin sector is therefore just two twin tops and one twin bottom. The LHC phenomenology, illustrated with two example models, is dominated by twin glueball decays, possibly in association with Higgs bosons. We further construct an explicit four-dimensional UV completion and discuss a variety of UV completions relevant for both vector-like and fraternal twin Higgs models. [ABSTRACT FROM AUTHOR]

We study Einstein-Born-Infeld gravity and construct the dyonic (A)dS planar black holes in general even dimensions, that carry both the electric charge and magnetic fluxes along the planar space. In four dimensions, the solution can be constructed with also spherical and hyperbolic topologies. We study the black hole thermodynamics and obtain the first law. We also classify the singularity structure. [ABSTRACT FROM AUTHOR]

We study global symmetry groups of six-dimensional superconformal field theories (SCFTs). In the Coulomb branch we use field theoretical arguments to predict an upper bound for the global symmetry of the SCFT. We then analyze global symmetry groups of F-theory constructions of SCFTs with a one-dimensional Coulomb branch. While in the vast majority of cases, all of the global symmetries allowed by our Coulomb branch analysis can be realized in F-theory, in a handful of cases we find that F-theory models fail to realize the full symmetry of the theory on the Coulomb branch. In one particularly mysterious case, F-theory models realize several distinct maximal subgroups of the predicted group, but not the predicted group itself. [ABSTRACT FROM AUTHOR]

In this paper we elucidate the rigid limit of N = 2 supergravity coupled to vector and hypermultiplets. In particular we show how the respective scalar field spaces reduce to their global counterparts. In the hypermultiplet sector we focus on the relation between the local and rigid c-map. [ABSTRACT FROM AUTHOR]

Using a recently developed off-shell formulation for general 4D 풩 = 2 supergravity-matter systems, we propose a construction to generate higher derivative couplings. We address here mainly the interactions of tensor and vector multiplets, but the construction is quite general. For a certain subclass of terms, the action is naturally written as an integral over 3/4 of the Grassmann coordinates of superspace. [ABSTRACT FROM AUTHOR]

Fundamental physics began the twentieth century with the twin revolutions of relativity and quantum mechanics, and much of the second half of the century was devoted to the construction of a theoretical structure unifying these radical ideas. But this foundation has also led us to a number of paradoxes in our understanding of nature. Attempts to make sense of quantum mechanics and gravity at the smallest distance scales lead inexorably to the conclusion that spacetime is an approximate notion that must emerge from more primitive building blocks. Furthermore, violent short-distance quantum fluctuations in the vacuum seem to make the existence of a macroscopic world wildly implausible, and yet we live comfortably in a huge universe. What, if anything, tames these fluctuations? Why is there a macroscopic universe? These are two of the central theoretical challenges of fundamental physics in the twenty-first century. In this essay, I describe the circle of ideas surrounding these questions, as well as some of the theoretical and experimental fronts on which they are being attacked. [ABSTRACT FROM AUTHOR]

Abstract: Should nature be supersymmetric, then it will be described by Quantum Supergravity at least in some energy regimes. The currently most advanced description of Quantum Supergravity and beyond is Superstring Theory/M-Theory in 10/11 dimensions. String Theory is a top-to-bottom approach to Quantum Supergravity in that it postulates a new object, the string, from which classical Supergravity emerges as a low energy limit. On the other hand, one may try more traditional bottom-to-top routes and apply the techniques of Quantum Field Theory. Loop Quantum Gravity (LQG) is a manifestly background independent and non-perturbative approach to the quantisation of classical General Relativity, however, so far mostly without supersymmetry. The main obstacle to the extension of the techniques of LQG to the quantisation of higher dimensional Supergravity is that LQG rests on a specific connection formulation of General Relativity which exists only in dimensions. In this Letter we introduce a new connection formulation of General Relativity which exists in all space–time dimensions. We show that all LQG techniques developed in can be transferred to the new variables in all dimensions and describe how they can be generalised to the new types of fields that appear in Supergravity theories as compared to standard matter, specifically Rarita–Schwinger and p-form gauge fields. [Copyright &y& Elsevier]

Abstract: General formulae for the soft SUSY breaking terms, valid in any SUGRA context, were derived in the mid-nineties. Since SUSY is not expected to have quantum anomalies, they should be valid in the quantum theory and be RG invariant down to the soft SUSY breaking scale. This observation enables us to give a uniform treatment of all phenomenological models for SUSY breaking and transmission, such as AMSB, GMSB, etc. In particular we find that the much discussed RG invariant formulae for soft SUSY breaking parameters in AMSB, effectively depend on a strong assumption of factorizability of the matter Kaehler metric. We then argue that there is no necessity for having ad hoc constructions such as mAMSB to counteract the negative squared slepton mass problem, since the natural framework that emerges in a sequestered model is one in which gaugino masses are as in AMSB, and the other soft terms are generated by RG running as in gaugino mediation. [Copyright &y& Elsevier]

We present the explicit formulas relating Hopf maps with Wigner's little groups. They, particularly, explain simple action of group on a fiber for the first and second Hopf fibrations, and present most simplified form for the third one. Corresponding invariant Lagrangians are presented, and their possible reductions are discussed. [ABSTRACT FROM AUTHOR]

Abstract: We discuss a simple transformation that allows to generate structure solutions of Type IIB supergravity with RR fluxes, starting from non-Kähler solutions of Type I supergravity. The method may be applied also in the presence of supersymmetric source branes. We apply this transformation to a solution describing fivebranes wrapped on the of the resolved conifold with additional flavour fivebrane sources. The resulting solution is a generalisation of the resolved deformed conifold solution of Butti et al. (2005) by the addition of D5 brane and D3 brane sources. We propose that this solution may be interpreted in terms of a combined effect of Higgsing and cascade of Seiberg dualities in the dual field theory. [Copyright &y& Elsevier]

The idea that quantum gravity can be realized at the TeV scale is extremely attractive to theorists and experimentalists alike. This proposal leads to extra spacial dimensions large compared to the Planck scale. Here, we give a very systematic view of the foundations of the theories with large extra dimensions and their physical consequences. [ABSTRACT FROM AUTHOR]

Worldvolume actions for multiple M2 and D2 branes are constructed by taking the limit of 2 + 1 dimensional gauged supergravities to globally supersymmetric = 8 theories on flat space. The embedding tensor formalism adopted for the classification of gauged supergravities is thereby shown to provide a universal description of all known models, including conformal and nonconformal theories as well as massive deformations thereof. [ABSTRACT FROM AUTHOR]

We review a model of D-term dominated chaotic inflation in supergravity. The F-flat direction present in this model is lifted by the dominant D-term, which leads to chaotic inflation and subsequent reheating. The leptogenesis scenario via the inflaton decay in this D-term chaotic inflation scenario is also discussed. [ABSTRACT FROM AUTHOR]

We review on a recent construction of the on-shell supersymmetric brane action for the codimension-two branes with nonzero tension in the flux compactification of a 6D chiral gauged supergravity. On dimensionally reducing on 4D gauged supergravity for a new supersymmetric unwarped background with conical branes, we consider the modulus stabilization for determining the soft masses of the scalars localized on the branes and show that the bulk U(1)R provides a new mechanism for mediating the SUSY breaking. [ABSTRACT FROM AUTHOR]

This is a brief review of the superspace formulation for fivedimensional = 1 mattercoupled supergravity recently developed by the authors. [ABSTRACT FROM AUTHOR]

Abstract: Apply the T-duality and smeared twist to the D3-brane solution one can construct the supergravity backgrounds which may dual to supersymmetric or non-supersymmetric non-commutative dipole field theory. We introduce D7-brane probe into the dual supergravity background to study the chiral dynamics and meson spectrum therein. We first find that the non-commutative dipole field does not induce the chiral symmetry breaking even if the supersymmetry was completely broken, contrast to the conventional believing that the chiral symmetry will be broken in the non-supersymmetric theory. Next, we find that the dipole field does not modify the meson spectrum in the supersymmetric theory while it will reduce the meson bound-state energy in the non-supersymmetric theory. We also evaluate the static quark–anti-quark potential and see that the dipole field has an effect to produce attractive force between the quark and anti-quark. [Copyright &y& Elsevier]

Even though the chaotic inflation is one of the most popular inflation models for its simple dynamics and compelling resolutions to the initial condition problems, its realization in supergravity has been considered a challenging task. We discuss how the chaotic inflation dominated by the D-term can be induced in supergravity, which would give a new perspective on the inflation model building in supergravity. [ABSTRACT FROM AUTHOR]

We review the matter induced part of the effective superpotential of $\mathcal{N} = 2$, U(N) gauge model in which $\mathcal{N} = 2$ supersymmetry is spontaneously broken to $\mathcal{N} = 1$. We derive this by the diagrammatical computation and by using the properties of the chiral ring and the generalized Konishi anomaly equations. [ABSTRACT FROM AUTHOR]

Abstract: The holomorphicity property of superpotentials or of F-terms involving vector multiplets is generalized to the case of 1/2-BPS effective operators defined in harmonic superspace. The resulting harmonicity equations are shown to control the moduli dependence of the couplings of higher-dimensional operators involving powers of the Weyl superfield, computed by topological amplitudes. These equations can also be derived on the string side, exhibiting an anomaly from world-sheet boundary contributions that leads to recursion relations for the non-analytic part of the couplings. [Copyright &y& Elsevier]

The ten dimensional string theories as well as eleven dimensional supergravity are conjectured to arise as limits of a more basic theory, traditionally dubbed M-theory. This notion is confined to the ten dimensional supersymmetric theories. String theory, however, also contains ten dimensional non-supersymmetric theories that have not been incorporated into this picture. In this note we explore the possibility of generating the low energy spectra of various non-supersymmetric heterotic string vacua from the Horava–Witten model. We argue that this can be achieved by imposing on the Horava–Witten model an invariance with respect to some extra operators which identify the orbifold fixed planes in a non-trivial way, and we demonstrate it for the E8 and SO(16)×SO(16) heterotic string vacua in ten dimensions. [ABSTRACT FROM AUTHOR]

The 14 Killing vectors of the target space for five-dimensional minimal supergravity reduced to three dimensions are explicitly constructed in terms of the original field variables. These vectors generate the Lie algebra of G2. We also construct a symmetrical 7×7 matrix representative of the coset G2(+2)/((SL(2,R)×SL(2,R)) as a function of the same fields. [ABSTRACT FROM AUTHOR]