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8 papers found.
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Hodge numbers for all CICY quotients

We present a general method for computing Hodge numbers for Calabi-Yau manifolds realised as discrete quotients of complete intersections in products of projective spaces. The method relies on the computation of equivariant cohomologies and is illustrated for several explicit examples. In this way, we compute the Hodge numbers for all discrete quotients obtained in Braun’s...

Matter field Kähler metric in heterotic string theory from localisation

AbstractWe propose an analytic method to calculate the matter field Kähler metric in heterotic compactifications on smooth Calabi-Yau three-folds with Abelian internal gauge fields. The matter field Kähler metric determines the normalisations of the \( \mathcal{N} \) = 1 chiral superfields, which enter the computation of the physical Yukawa couplings. We first derive the general...

The family problem: hints from heterotic line bundle models

Within the class of heterotic line bundle models, we argue that \( \mathcal{N}=1 \) vacua which lead to a small number of low-energy chiral families are preferred. By imposing an upper limit on the volume of the internal manifold, as required in order to obtain finite values of the four-dimensional gauge couplings, and validity of the supergravity approximation we show that, for...

A heterotic standard model with B − L symmetry and a stable proton

We consider heterotic Calabi-Yau compactifications with S(U(4) × U(1)) background gauge fields. These models lead to gauge groups with an additional U(1) factor which, under certain conditions, can combine with hypercharge to a B − L symmetry. The associated gauge boson is automatically super-massive and, hence, does not constitute a phenomenological problem. We illustrate this...

The moduli space of heterotic line bundle models: a case study for the tetra-quadric

It has recently been realised that polystable, holomorphic sums of line bundles over smooth Calabi-Yau three-folds provide a fertile ground for heterotic model building. Large numbers of phenomenologically promising such models have been constructed for various classes of Calabi-Yau manifolds. In this paper we focus on a case study for the tetra-quadric—a Calabi-Yau hypersurface...

Type IIB flux vacua from G-theory II

Abstract We find analytic solutions of type IIB supergravity on geometries that locally take the form Mink × M 4 × ℂ with M 4 a generalised complex manifold. The solutions involve the metric, the dilaton, NSNS and RR flux potentials (oriented along the M 4) parametrised by functions varying only over ℂ. Under this assumption, the supersymmetry equations are solved using the...

A Comprehensive Scan for Heterotic SU(5) GUT models

Abstract Compactifications of heterotic theories on smooth Calabi-Yau manifolds remain one of the most promising approaches to string phenomenology. In two previous papers, arXiv:1106.4804 and arXiv:1202.1757, large classes of such vacua were constructed, using sums of line bundles over complete intersection Calabi-Yau manifolds in products of projective spaces that admit smooth...