Soft supersymmetry-breaking terms from supergravity and superstring models

We review the origin of soft supersymmetry-breaking terms in N=1 supergravity models of particle physics. We first consider general formulae for those terms in general models with a hidden sector breaking supersymmetry at an intermediate energy scale. The results for some simple models are given. We then consider the results obtained in some simple superstring models in which particular assumptions about the origin of supersymmetry breaking are made. These are models in which the seed of supersymmetry breaking is assumed to be originated in the dilaton/moduli sector of the theory.Comment: 24 pages, to appear in the book `Perspectives on Supersymmetry', World Scientific, Editor G. Kane; some comments and references adde

Exactly solvable pairing model for superconductors with a p+ip-wave symmetry

We present the exact Bethe ansatz solution for the two-dimensional BCS pairing Hamiltonian with p_x + i p_y symmetry. Using both mean-field theory and the exact solution we obtain the ground-state phase diagram parameterized by the filling fraction and the coupling constant. It consists of three phases denoted weak coupling BCS, weak pairing, and strong pairing. The first two phases are separated by a topologically protected line where the exact ground state is given by the Moore-Read pfaffian state. In the thermodynamic limit the ground-state energy is discontinuous on this line. The other two phases are separated by the critical line, also topologically protected, previously found by Read and Green. We establish a duality relation between the weak and strong pairing phases, whereby ground states of the weak phase are "dressed" versions of the ground states of the strong phase by zero energy (Moore-Read) pairs and characterized by a topological order parameter.Comment: 4 pages, 2 figures. Discussion on winding numbers added. Accepted in Phys Rev

Gauge Coupling Unification in Superstring Derived Standard--like Models

I discuss gauge coupling unification in a class of superstring standard--like models, which are derived in the free fermionic formulation. Recent calculations indicate that the superstring unification scale is at $O(10^{18}GeV)$ while the minimal supersymmetric standard model is consistent with LEP data if the unification scale is at $O(10^{16})GeV$. A generic feature of the superstring standard--like models is the appearance of extra color triplets $(D,{\bar D})$, and electroweak doublets $(\ell,{\bar\ell})$, in vector--like representations, beyond the minimal supersymmetric standard model. I show that gauge coupling unification at $O(10^{18}GeV)$ in the superstring standard--like models can be consistent with LEP data. I present an explicit standard--like model that can realize superstring gauge coupling unification.Comment: WIS--92/17/FEB--PH, 12 page

Introduction to the AdS/CFT correspondence

This is a pedagogical introduction to the AdS/CFT correspondence, based on lectures delivered by the author at the third IDPASC school. Starting with the conceptual basis of the holographic dualities, the subject is developed emphasizing some concrete topics, which are discussed in detail. A very brief introduction to string theory is provided, containing the minimal ingredients to understand the origin of the AdS/CFT duality. Other topics covered are the holographic calculation of correlation functions, quark-antiquark potentials and transport coefficients.Comment: 64 pages, 12 figures;v2: minor improvements;v3: references adde

Trinification with sin^2\theta_W^0=3/8 and seesaw neutrino mass

We realize a supersymmetric trinification model with three families of $({\bf 27}_{\rm tri}+{\bf 27}_{\rm tri} +\bar{\bf 27}_{\rm tri})$ by the $Z_3$ orbifold compactification with two Wilson lines. It is possible to break the trinification group to the supersymmetric standard model. This model has several interesting features: the {\it hypercharge quantization}, $\sin^2\theta_W^0=\frac38,$ naturally light neutrino masses, and introduction of R-parity. The {\it hypercharge quantization} is realized by the choice of the vacuum, naturally leading toward a supersymmetric standard model.Comment: 15 page

Inverting the Supersymmetric Standard Model Spectrum: from Physical to Lagrangian Ino Parameters

We examine the possibility of recovering the supersymmetric (and soft supersymmetry breaking) Lagrangian parameters as direct {\em analytical} expressions of appropriate physical masses, for the unconstrained (but CP and R-parity conserving) minimal supersymmetric standard model. We concentrate mainly on the algebraically non-trivial "inversion" for the ino parameters, and obtain, for given values of $\tan\beta$, simple analytical expressions for the $\mu$, $M_1$ and $M_2$ parameters in terms of three arbitrary input physical masses, namely either two chargino and one neutralino masses, or alternatively one chargino and two neutralino masses. We illustrate and discuss in detail the possible occurrence of ambiguities in this reconstruction. The dependence of the resulting ino Lagrangian parameters upon physical masses is illustrated, and some simple generic behaviour uncovered in this way. We finally briefly sketch generalizing such an inversion to the full set of MSSM Lagrangian parameters.Comment: Latex, 28 pages, 6 figures, 1 table, some typos corrected, one paragraph extended in section 4.2. Version to appear in Phys. Rev.

Anomalies in field theories with extra dimensions

We give an overview of the issue of anomalies in field theories with extra dimensions. We start by reviewing in a pedagogical way the computation of the standard perturbative gauge and gravitational anomalies on non-compact spaces, using Fujikawa's approach and functional integral methods, and discuss the available mechanisms for their cancellation. We then generalize these analyses to the case of orbifold field theories with compact internal dimensions, emphasizing the new aspects related to the presence of orbifold singularities and discrete Wilson lines, and the new cancellation mechanisms that are becoming available. We conclude with a very brief discussion on global and parity anomalies.Comment: Review article written for Int.J.Mod.Phys. A, 63 pages; v2: mistake in subsection 4.3 corrected, some comments and references added, a few misprints fixe

Estado epiléptico no convulsivo en el siglo XXI: clínica, diagnóstico, tratamiento y pronóstico

Non-convulsive status epilepticus is a significant issue for a neurologist because, despite its low prevalence, it mimics other pathologies, with therapeutics and prognostic outcomes. Diagnosis is based on clinical features, mainly mental status or impaired consciousness and electroencephalographic changes, so electroencephalogram is the first exploration we must perform with clinical suspicion. There are three clinical forms: generalized or absence status, with diffuse epileptiform discharges; focal, with epileptic discharges located in a specific brain area and may not affect consciousness; and subtle, with diffuse or local epileptic activity after a tonic-clonic seizure or convulsive status and limited or no motor activity. Treatment are benzodiazepines and antiepileptic drugs; anesthetic drugs are only recommended for patients with subtle status and in some with partial complex status. Prognosis is mainly determined by etiology and associated brain damage