The Standard Model Higgs as the origin of the hot Big Bang

If the Standard Model (SM) Higgs is weakly coupled to the inflationary sector, the Higgs is expected to be universally in the form of a condensate towards the end of inflation. The Higgs decays rapidly after inflation - via non-perturbative effects - into an out-of-equilibrium distribution of SM species, which thermalize soon afterwards. If the post-inflationary equation of state of the universe is stiff, $w \simeq +1$, the SM species eventually dominate the total energy budget. This provides a natural origin for the relativistic thermal plasma of SM species, required for the onset of the `hot Big Bang' era. The viability of this scenario requires the inflationary Hubble scale $H_*$ to be lower than the instability scale for Higgs vacuum decay, the Higgs not to generate too large curvature perturbations at cosmological scales, and the SM dominance to occur before Big Bang Nucleosynthesis. We show that successful reheating into the SM can only be obtained in the presence of a non-minimal coupling to gravity $\xi \gtrsim 1$, with a reheating temperature of $T_{\rm RH} \gtrsim \mathcal{O}(10^{10})\xi^{3/2}(H_*/10^{14}{\rm GeV})^2~{\rm GeV}$.Comment: 6 pages, 2 figures, minor changes with new figures to match published version in PL

Classification of IIB backgrounds with 28 supersymmetries

We show that all IIB backgrounds with strictly 28 supersymmetries are locally isometric to the plane wave solution of arXiv:hep-th/0206195. Moreover, we demonstrate that all solutions with more than 26 supersymmetries and only 5-form flux are maximally supersymmetric. The N=28 plane wave solution is a superposition of the maximally supersymmetric IIB plane wave with a heterotic string solution. We investigate the propagation of strings in this background, find the spectrum and give the string light-cone Hamiltonian.Comment: 30 pages, typos correcte

THE EFFECT OF A 7-WEEK PROGRESSIVE YOGA INTERVENTION ON HAMSTRINGS FLEXIBILITY

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Supersymmetry and homogeneity of M-theory backgrounds

We describe the construction of a Lie superalgebra associated to an arbitrary supersymmetric M-theory background, and discuss some examples. We prove that for backgrounds with more than 24 supercharges, the bosonic subalgebra acts locally transitively. In particular, we prove that backgrounds with more than 24 supersymmetries are necessarily (locally) homogeneous.Comment: 19 pages (Erroneous Section 6.3 removed from the paper.

Constraints on the near-Earth asteroid obliquity distribution from the Yarkovsky effect

Aims. From lightcurve and radar data we know the spin axis of only 43 near-Earth asteroids. In this paper we attempt to constrain the spin axis obliquity distribution of near-Earth asteroids by leveraging the Yarkovsky effect and its dependence on an asteroid’s obliquity. Methods. By modeling the physical parameters driving the Yarkovsky effect, we solve an inverse problem where we test different simple parametric obliquity distributions. Each distribution results in a predicted Yarkovsky effect distribution that we compare with a X2 test to a dataset of 125 Yarkovsky estimates. Results. We find different obliquity distributions that are statistically satisfactory. In particular, among the considered models, the best-fit solution is a quadratic function, which only depends on two parameters, favors extreme obliquities, consistent with the expected outcomes from the YORP effect, has a 2:1 ratio between retrograde and direct rotators, which is in agreement with theoretical predictions, and is statistically consistent with the distribution of known spin axes of near-Earth asteroids

Estrategias de Comunicación Participativa, Saneamiento Básico y la Salud Pública de los Pobladores de Paucartambo-Cusco: Participatory Communication Strategies, Basic Sanitation and Public Health of the People of Paucartambo-Cusco

Objectives: To analyze the influence that the application of participatory communication strategies has on the adequate use of basic sanitation services and its impact on the public health of the residents of communities in Paucartambo. Explore the political and cultural dimensions immersed in the communication processes between populations and health promoters of the study communities. Analyze the intervention processes in the field of health communication. Methods: The type of research is qualitative and observational, with a cross-sectional design based on unstructured interviews and in-depth interviews. Data from the National Population and Housing Censuses 2017, 2007 - National Institute of Statistics and Informatics were used. (INEI) - PERU. Results: In-depth interviews, as well as direct observation, result in the fact that although efforts have been made to improve the situation of basic sanitation through the installation of a public sewage network, and other forms such as latrines and septic tanks In addition to being insufficient, they were not used properly, because participatory communication strategies were not applied from the diagnostic stage to the final evaluation, even more so due to the permanent lack of monitoring and surveillance activities, which have a very decisive role in the quality of life and therefore in public health Conclusion: The communication strategies most used by institutions that have the role of promoting the adequate use of basic sanitation services such as public sewage networks have been of a vertical nature such as those talks, radio, the use of pictures, precisely for this reason, adequate knowledge, attitudes and practices were not generated s for their use and conservation, a situation that had negative impacts on public and environmental health.Objetivos: Analizar la influencia que tiene la aplicación de estrategias de comunicación participativa en el uso adecuado de servicios de saneamiento básico y su incidencia en la salud pública de los pobladores de comunidades de Paucartambo. Explorar las dimensiones políticas y culturales inmersas en los procesos de comunicación entre poblaciones y promotores de salud de las comunidades de estudio Analizar los procesos de intervención en el campo de la comunicación en salud. Métodos: El tipo de investigación es cualitativo y observacional, con un diseño de tipo transversal en base a entrevistas no estructuradas y entrevistas en profundidad, Se utilizó los datos de los Censos Nacionales de Población y Vivienda 2017, 2007- Instituto Nacional de Estadística e Informática (INEI) - PERÚ. Resultados: Las entrevistas a profundidad, así como la observación directa, dan como resultado que si bien se han realizado esfuerzos por mejorar la situación del saneamiento básico a través de la instalación de red pública de desagüe, y otras formas como las letrinas y pozos sépticos, además de ser insuficientes, no fueron utilizados adecuadamente, porque no se aplicaron estrategias de comunicación participativa desde la etapa de diagnóstico, hasta la evaluación final, más aun por la falta permanente de actividades de monitoreo y vigilancia, que tienen un rol muy decisivo en la calidad de vida y por tanto en la salud pública Conclusión: Las estrategias de comunicación más utilizadas por las instituciones que tienen el rol de promover el uso adecuado de los servicios de saneamiento básico como las redes públicas de desagüe han sido de carácter vertical como las charlas, la radio, el uso de láminas, precisamente por esta razón no se generaron conocimientos, actitudes y prácticas adecuadas  para el uso y la conservación de los mismos, situación que tuvo impactos negativos sobre la salud pública y también ambiental

Parallelisable Heterotic Backgrounds

We classify the simply-connected supersymmetric parallelisable backgrounds of heterotic supergravity. They are all given by parallelised Lie groups admitting a bi-invariant lorentzian metric. We find examples preserving 4, 8, 10, 12, 14 and 16 of the 16 supersymmetries.Comment: 17 pages, AMSLaTe

Vibration Isolation Design for the Micro-X Rocket Payload

Micro-X is a NASA-funded, sounding rocket-borne X-ray imaging spectrometer that will allow high precision measurements of velocity structure, ionization state and elemental composition of extended astrophysical systems. One of the biggest challenges in payload design is to maintain the temperature of the detectors during launch. There are several vibration damping stages to prevent energy transmission from the rocket skin to the detector stage, which causes heating during launch. Each stage should be more rigid than the outer stages to achieve vibrational isolation. We describe a major design effort to tune the resonance frequencies of these vibration isolation stages to reduce heating problems prior to the projected launch in the summer of 2014.Comment: 6 pages, 7 figures, LTD15 Conference Proceeding