Fernando Quevedo

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We present an explicit calculation of the spectrum of a general class of string models, corresponding to Calabi-Yau flux compactifications with h1,2 > h1,1 > 1 with leading perturbative and non-perturbative corrections, in which all geometric moduli are stabilised as in hep-th/0502058. The volume is exponentially large, leading to a range of string scales(More)
We propose a new mechanism for obtaining de Sitter vacua in type IIB string theory compactified on (orientifolded) Calabi-Yau manifolds similar to those recently studied by Kachru, Kallosh, Linde and Trivedi (KKLT). dS vacuum appears in KKLT model after uplifting an AdS vacuum by adding an anti-D3-brane, which explicitly breaks supersymmetry. We accomplish(More)
We show how the motion through the extra dimensions of a gas of branes and antibranes can, under certain circumstances, produce an era of inflation as seen by observers trapped on a 3-brane, with the inflaton being the inter-brane separation. Although most of our discussion refers to arbitrary p-branes, when we need to be specific we assume that they are(More)
G. Aldazabal, L. E. Ibáñez, F. Quevedo and A. M. Uranga 1 Instituto Balseiro, CNEA, Centro Atómico Bariloche, 8400 S.C. de Bariloche, and CONICET, Argentina. 2 Departamento de F́ısica Teórica C-XI and Instituto de F́ısica Teórica C-XVI, Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain. 3 DAMTP, Wilberforce Road, Cambridge, CB3 0WA, England.(More)
This paper develops the computation of soft supersymmetry breaking terms for chiral D7 matter fields in IIB Calabi-Yau flux compactifications with stabilised moduli. We determine explicit expressions for soft terms for the single-modulus KKLT scenario and the multiple-moduli large volume scenario. In particular we use the chiral matter metrics for(More)
We describe the construction of string theory models with semirealistic spectrum in a sector of (anti) D3-branes located at an orbifold singularity at the bottom of a highly warped throat geometry, which is a generalisation of the Klebanov-Strassler deformed conifold. These models realise the Randall-Sundrum proposal to naturally generate the(More)
We study the spectrum, couplings and cosmological and astrophysical implications of the moduli fields for the class of Calabi-Yau IIB string compactifications for which moduli stabilisation leads to an exponentially large volume V ∼ 1015l6 s and an intermediate string scale ms ∼ 1011 GeV, with TeV-scale observable supersymmetry breaking. All Kähler moduli(More)
We study the behaviour of the string loop corrections to the N = 1 4D supergravity Kähler potential that occur in flux compactifications of IIB string theory on general Calabi-Yau three-folds. We give a low energy interpretation for the conjecture of Berg, Haack and Pajer for the form of the loop corrections to the Kähler potential. We check the consistency(More)
High-precision analyses of supersymmetry parameters aim at reconstructing the fundamental supersymmetric theory and its breaking mechanism. A well defined theoretical framework is needed when higher-order corrections are included. We propose such a scheme, Supersymmetry Parameter Analysis SPA, based on a consistent set of conventions and input parameters. A(More)
We study the different phases of field theories of compact antisymmetric tensors of rank h − 1 in arbitrary space-time dimensions D = d + 1. Starting in a ‘Coulomb’ phase, topological defects of dimension d− h− 1 ((d− h− 1)-branes) may condense leading to a generalized ‘confinement’ phase. If the dual theory is also compact the model may also have a third,(More)