Quantum simulation of an extra dimension

We present a general strategy to simulate a D+1-dimensional quantum system using a D-dimensional one. We analyze in detail a feasible implementation of our scheme using optical lattice technology. The simplest non-trivial realization of a fourth dimension corresponds to the creation of a bivolume geometry. We also propose single- and many-particle experimental signatures to detect the effects of the extra dimension.Comment: 5 pages, 3 figures, revtex style;v2 minor changes, references adde

Synthetic gauge fields in synthetic dimensions

We describe a simple technique for generating a cold-atom lattice pierced by a uniform magnetic field. Our method is to extend a one-dimensional optical lattice into the "dimension" provided by the internal atomic degrees of freedom, yielding a synthetic 2D lattice. Suitable laser-coupling between these internal states leads to a uniform magnetic flux within the 2D lattice. We show that this setup reproduces the main features of magnetic lattice systems, such as the fractal Hofstadter butterfly spectrum and the chiral edge states of the associated Chern insulating phases.Comment: 5+4 pages, 5+3 figures, two-column revtex; v2: discussion of role of interactions added, Fig. 1 reshaped, minor changes, references adde

Dynamic Clinical Data Mining: Search Engine-Based Decision Support

The research world is undergoing a transformation into one in which data, on massive levels, is freely shared. In the clinical world, the capture of data on a consistent basis has only recently begun. We propose an operational vision for a digitally based care system that incorporates data-based clinical decision making. The system would aggregate individual patient electronic medical data in the course of care; query a universal, de-identified clinical database using modified search engine technology in real time; identify prior cases of sufficient similarity as to be instructive to the case at hand; and populate the individual patient's electronic medical record with pertinent decision support material such as suggested interventions and prognosis, based on prior outcomes. Every individual's course, including subsequent outcomes, would then further populate the population database to create a feedback loop to benefit the care of future patients

Simulation of gauge transformations on systems of ultracold atoms

We show that gauge transformations can be simulated on systems of ultracold atoms. We discuss observables that are invariant under these gauge transformations and compute them using a tensor network ansatz that escapes the phase problem. We determine that the Mott-insulator-to-superfluid critical point is monotonically shifted as the induced magnetic flux increases. This result is stable against the inclusion of a small amount of entanglement in the variational ansatz.Comment: 14 pages, 6 figure

Flow Equations for Non-BPS Extremal Black Holes

We exploit some common features of black hole and domain wall solutions of (super)gravity theories coupled to scalar fields and construct a class of stable extremal black holes that are non-BPS, but still can be described by first-order differential equations. These are driven by a "superpotential'', which replaces the central charge Z in the usual black hole potential. We provide a general procedure for finding this class and deriving the associated "superpotential''. We also identify some other cases which do not belong to this class, but show a similar behaviour.Comment: LaTeX, 21 pages, 2 figures. v2: reference added, JHEP versio

Transformación digital como proceso generador de valor público para el ciudadano

The objective of this study was to investigate the experience of the digital transformation process of public institutions aimed at providing basic public services as a value generator for the relationship with the citizen. It is a basic investigation, with a hermeneutic-interpretative metodology. A semi-structured interview guide was developed for participants selected for convenience. The interviewees were experts in digital transformation of the public sector and informants involved in the process. Three procedural stages were developed: the exploratory one, where the a priori categories were identified: governance framework, digital strategy and culture, technological infrastructure, digitalization route and the citizen approach; the descriptive stage, the direct approximation of the study phenomenon was carried out, whose information was processed in licensed Atlas.ti software; finally, in the structural stage the experience was built. The findings show that the digital transformation was not formulated from the pillar of innovation, which puts the needs of people at the center as a generator of value. The governance framework is not enough to develop the digital strategy and roadmap; institutional leadership and the culture of the organization constitute barriers or enablers in the management of efficient processes.El objetivo de este estudio fue indagar sobre la experiencia del proceso de transformación digital de las instituciones públicas orientadas a brindar servicios básicos públicos como generador de valor para el relacionamiento con el ciudadano. Es una investigación básica, con un diseño hermenéutico-interpretativo. Se elaboró una guía de entrevista semiestructurada para participantes seleccionados por conveniencia. Los entrevistados fueron expertos en transformación digital del sector público e informantes involucrados en el proceso. Se desarrollaron tres etapas procedimentales: la exploratoria, en donde se identificaron las categorías apriorísticas: marco de gobernanza, estrategia y cultura digital, infraestructura tecnológica, ruta de digitalización y el enfoque al ciudadano; la etapa descriptiva, se realizó la aproximación directa del fenómeno de estudio, cuya información se procesó en el programa Atlas.ti, bajo licencia; finalmente, en la etapa estructural se construyó la experiencia. Los hallazgos muestran que la transformación digital no se formuló desde el pilar de la innovación, que pone en el centro las necesidades de las personas como generador de valor. El marco de gobernanza no es suficiente para desarrollar la estrategia y la ruta digital; el liderazgo institucional y la cultura de la organización se constituyen en barreras o habilitadores en la gestión de procesos eficiente

Null Deformed Domain Wall

We study null 1/4 BPS deformations of flat domain wall solutions (NDDW) in N=2, d=5 gauged supergravity with hypermultiplets and vector multiplets coupled. These are uncharged time-dependent configurations and contain as special case, 1/2 supersymmetric flat domain walls (DW), as well as 1/2 BPS null solutions of the ungauged supergravity. Combining our analysis with the classification method initiated by Gauntlett et al., we prove that all the possible deformations of the DW have origin in the hypermultiplet sector or/and are null. Here, we classify all the null deformations: we show that they naturally organize themselves into "gauging" (v-deformation) and "non gauging" (u-deformation). They have different properties: only in presence of v-deformation is the solution supported by a time-dependent scalar potential. Furthermore we show that the number of possible deformations equals the number of matter multiplets coupled. We discuss the general procedure for constructing explicit solutions, stressing the crucial role taken by the integrability conditions of the scalars as spacetime functions. Two analytical solutions are presented. Finally, we comment on the holographic applications of the NDDW, in relation to the recently proposed time-dependent AdS/CFT.Comment: 38 pages; minor changes, references added; text revised, minor changes, final version published in JHE