Gauge transformations for higher-order lagrangians

Noether's symmetry transformations for higher-order lagrangians are studied. A characterization of these transformations is presented, which is useful to find gauge transformations for higher-order singular lagrangians. The case of second-order lagrangians is studied in detail. Some examples that illustrate our results are given; in particular, for the lagrangian of a relativistic particle with curvature, lagrangian gauge transformations are obtained, though there are no hamiltonian gauge generators for them.Comment: 22 pages, LaTe

How Ordinary Elimination Became Gaussian Elimination

Newton, in notes that he would rather not have seen published, described a process for solving simultaneous equations that later authors applied specifically to linear equations. This method that Euler did not recommend, that Legendre called "ordinary," and that Gauss called "common" - is now named after Gauss: "Gaussian" elimination. Gauss's name became associated with elimination through the adoption, by professional computers, of a specialized notation that Gauss devised for his own least squares calculations. The notation allowed elimination to be viewed as a sequence of arithmetic operations that were repeatedly optimized for hand computing and eventually were described by matrices.Comment: 56 pages, 21 figures, 1 tabl

Testing the inverse-Compton catastrophe scenario in the intra-day variable blazar S5 0716+71. I. Simultaneous broadband observations during November 2003

Some intra-day variable, compact extra-galactic radio sources show brightness temperatures severely exceeding 10^{12} K, the limit set by catastrophic inverse-Compton (IC) cooling in sources of incoherent synchrotron radiation. The violation of the IC limit, possible under non-stationary conditions, would lead to IC avalanches in the soft-gamma-ray energy band during transient periods. For the first time, broadband signatures of possible IC catastrophes were searched for in S5 0716+71. A multifrequency observing campaign targetting S5 0716+71 was carried out in November 2003 under the framework of the European Network for the Investigation of Galactic nuclei through Multifrequency Analysis (ENIGMA) together with a campaign by the Whole Earth Blazar Telescope (WEBT), involving a pointing by the soft-gamma-ray satellite INTEGRAL, optical, near-infrared, sub-millimeter, millimeter, radio, and Very Long Baseline Array (VLBA) monitoring. S5 0716+71 was very bright at radio frequencies and in a rather faint optical state during the INTEGRAL pointing; significant inter-day and low intra-day variability was recorded in the radio regime, while typical fast variability features were observed in the optical band. No correlation was found between the radio and optical emission. The source was not detected by INTEGRAL, neither by the X-ray monitor JEM-X nor by the gamma-ray imager ISGRI, but upper limits to the source emission in the 3-200 keV energy band were estimated. A brightness temperature Tb>2.1x10^{14} K was inferred from the radio variability, but no corresponding signatures of IC avalanches were recorded at higher energies. The absence of IC-catastrophe signatures provides either a lower limit delta>8 to the Doppler factor affecting the radio emission or strong constraints for modelling of the Compton catastrophes in S5 0716+71.Comment: 15 pages, 3 EPS figures, 3 tables, to appear in A&

Evaluación de Parámetros de control obligatorio del agua potable proveniente del manantial Cuyuraya de la provincia de Huancané – Región Puno, 2019

El objetivo de este estudio fue el de evaluar los parámetros de control obligatorio de agua potable en la provincia de Huancané. Los puntos de monitoreo fueron seleccionados según la ubicación establecida por la Empresa Prestadora de Servicios “EPS NOR PUNO S.A.”; con los siguientes puntos: fuente principal de abastecimiento de agua (manantial Cuyuraya) y la red principal de abastecimiento (desde la primera vivienda, zona media y vivienda final) siendo un total de 6 puntos de monitoreo. Los parámetros evaluados según Reglamento de la Calidad del Agua para Consumo Humano DS N° 031 – 2010 – SA, fueron: pH, color, cloro residual, turbiedad, coliformes totales y termotolerantes, los cuales fueron analizados in-situ o en un laboratorio respectivamente, con un resultado de que solo 3 de los 6 parámetros evaluados cumplen con lo que indica el reglamento, debido a que Cloro Residual no llega al mínimo establecido de 0.5 mg/L, Coliformes Totales y Termotolerantes exceden en 16 UFC como máximo y <1.1 como mínimo, concluyendo que el agua que se distribuye en todo Huancané es directamente afectada por los niveles bajos de cloro residual, ocasionando que exista la presencia de coliformes (totales y termotolerantes), lo que afecta directamente a la calidad del agua que se distribuye en la provincia de Huancané.Trabajo de investigaciónJULIACAEscuela Profesional de Ingeniería AmbientalBiodiversidad y calidad ambienta