The Inflaton as a MSSM Higgs and Open String Modulus Monodromy Inflation

It has been recently pointed out that the polarization BICEP2 results are consistent with the identification of an inflaton mass m \simeq 10^{13} GeV with the SUSY breaking scale in an MSSM with a fine-tuned SM Higgs. This identification leads to a Higgs mass m_h \simeq 126 GeV, consistent with LHC measurements. Here we propose that this naturally suggests to identify the inflaton with the heavy MSSM Higgs system. The fact that the extrapolated Higgs coupling lambda_{SM}\simeq 0 at scales below the Planck scale suggests the Higgs degrees of freedom could be associated to a Wilson line or D-brane position modulus in string theory. The Higgs system then has a shift symmetry and an N=2 structure which guarantees that its potential has an approximate quadratic chaotic inflation form. These moduli in string compactifications, being compact, allow for a trans-Planckian inflaton field range analogous to a version of monodromy inflation.Comment: 6 pages. Misprints corrected, references adde

Minkowski 3-forms, Flux String Vacua, Axion Stability and Naturalness

We discuss the role of Minkowski 3-forms in flux string vacua. In these vacua all internal closed string fluxes are in one to one correspondence with quantized Minkowski 4-forms. By performing a dimensional reduction of the $D=10$ Type II supergravity actions we find that the 4-forms act as auxiliary fields of the Kahler and complex structure moduli in the effective action. We show that all the RR and NS axion dependence of the flux scalar potential appears through the said 4-forms. Gauge invariance of these forms then severely restricts the structure of the axion scalar potentials. Combined with duality symmetries it suggests that all perturbative corrections to the leading axion scalar potential $V_0$ should appear as an expansion in powers of $V_0$ itself. These facts could have an important effect e.g. on the inflaton models based on F-term axion monodromy. We also suggest that the involved multi-branched structure of string vacua provides for a new way to maintain interacting scalar masses stable against perturbative corrections.Comment: 39 pages. Typos corrected and added reference

Espectáculo y visualidad en la narrativa de Diamela Eltit

nota al margen del ensayo de Sergio Rojas Catástrofe y trascendencia en la narrativa de Diamela Eltit Sergio Rojas Santiago: Sangría editora, 2013

Gregorio Ossa Cerda y “Ossa y Escobar”. Un banco de avíos mineros, 1855-1884

En el presente artículo se estudia un ejemplo de las instituciones de crédito creadas a mediados del siglo XIX para el fomento de la actividad minera en la zona de Atacama. La firma “Ossa y Escobar”, creada en 1855 por el rico banquero copiapino Gregorio Ossa Cerda, se convirtió en uno de los habilitadores mas importantes de la zona de Atacama, en pleno crecimiento debido al descubrimiento de ricas minas de plata como Tres Puntas y Chimbero en la década de 1840, y posteriormente extendió sus actividades al mineral boliviano de Caracoles, descubierto en 1870. Sin embargo, la no diversificación de sus actividades, y la decadencia de las explotaciones mineras, condujo a la decadencia y liquidación final de la firma en 1884

Performance of adaptive bayesian equalizers in outdoor environments

Outdoor communications are affected by multipath propagation that imposes an upper limit on the system data rate and restricts possible applications. In order to overcome the degrading effect introduced by the channel, conventional equalizers implemented with digital filters have been traditionally used. A new approach based on neural networks is considered. In particular, the behavior of the adaptive Bayesian equalizer implemented by means of radial basis functions applied to the channel equalization of radio outdoor environments has been analyzed. The method used to train the equalizer coefficients is based on a channel response estimation. We compare the results obtained with three channel estimation methods: the least sum of square errors (LSSE) channel estimation algorithm, recursive least square (RLS) algorithm employed only to obtain one channel estimation and, finally, the RLS algorithm used to estimate the channel every decided symbol for the whole frame.Peer ReviewedPostprint (published version

Flux-induced Soft Terms on Type IIB/F-theory Matter Curves and Hypercharge Dependent Scalar Masses

Closed string fluxes induce generically SUSY-breaking soft terms on supersymmetric type IIB orientifold compactifications with D3/D7 branes. This was studied in the past by inserting those fluxes on the DBI+CS actions for adjoint D3/D7 fields, where D7-branes had no magnetic fluxes. In the present work we generalise those computations to the phenomenologically more relevant case of chiral bi-fundamental fields laying at 7-brane intersections and F-theory local matter curves. We also include the effect of 7-brane magnetic flux as well as more general closed string backgrounds, including the effect of distant (anti-)D3-branes. We discuss several applications of our results. We find that squark/slepton masses become in general flux-dependent in F-theory GUT's. Hypercharge-dependent non-universal scalar masses with a characteristic sfermion hierarchy m_E^2 < m_L^2 < m_Q^2 < m_D^2 < m_U^2 are obtained. There are also flavor-violating soft terms both for matter fields living at intersecting 7-branes or on D3-branes at singularities. They point at a very heavy sfermion spectrum to avoid FCNC constraints. We also discuss the possible microscopic description of the fine-tuning of the EW Higgs boson in compactifications with a MSSM spectrum.Comment: 67 pages, 2 figures, 2 table

Contratos inmobiliarios

Luis Heredia Valenzuela (biografía): Abogado dominicano, egresado de la Universidad Nacional Pedro Henríquez Ureña (UNPHU). Realizó un posgrado en la Universidad de Wisconsin en materia de derecho e instituciones legales de los Estados Unidos y una maestría en Common Law Studies en el Centro de Leyes de la Universidad de Georgetown. Ha centrado su práctica profesional en las áreas de derecho administrativo, aviación civil, derecho corporativo, derecho inmobiliario, impuestos, derecho marítimo, asuntos monetarios-cambiarios-bancarios, seguros, medio ambiente, minería, telecomunicaciones y turismo. Trabaja en la firma Russin, Vecchi & Heredia Bonetti. Es autor de las publicaciones: «Algunas deficiencias e ilegalidades en la legislación monetaria y cambiaria de la República Dominicana»; «Sugerencias para su adecuación y EC Competition Rules: An Assessment of the Liberty or Freedom of Contract Principle in Distribution Agreements in the EC and in Non EC Countries».Dado el dinamismo y crecimiento del sector inmobiliario en la República Dominicana durante la década de los 90, el autor se propuso que su contribución al debate jurídico estribara en una clara clasificación de los distintos tipos de contratos que tienen por objeto los inmuebles: sus características principales y los procedimientos con que debían ser completados son aquí especificados. Asimismo, una relación de sus cargas impositivas, de acuerdo con la ley dominicana, se encuentra al final de este trabajo