13,348 research outputs found

    Multidimensional quantum cosmic models: New solutions and gravitational waves

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    This paper contains a discussion on the quantum cosmic models, starting with the interpretation that all of the accelerating effects in the current universe are originated from the existence of a nonzero entropy of entanglement. In such a realm, we obtain new cosmic solutions for any arbitrary number of spatial dimensions, studying the stability of these solutions, so as the emergence of gravitational waves in the realm of the most general models.Comment: 7 pages, 1 Figure, LaTe

    Accelerating Hilbert-Einstein universe without dynamic dark energy

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    By using an unmodified Einstein gravity theory it is shown that all of the speeding-up effects taking place in the current universe are entirely due to the quantum effects associated with the background radiation or to the combination of such effects with those derived from the presence of a cosmological constant, without invoking any dynamic dark energy component. We obtain that in both cases the universe accelerates at a rate slightly beyond what is predicted by a cosmological constant but does not induce any big rip singularity in the finite future.Comment: 7 pages, LaTex, to appear in Phys. Lett.

    A gracious exit from the matter-dominated phase in a quantum cosmic phantom model

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    The most recent observational constraints coming from Planck, when combined with other cosmological data, provide evidence for a phantom scenario. In this work we consider a quantum cosmic phantom model where both the matter particles and scalar field are associated with quantum potentials which make the effective mass associated with the matter particles to vanish at the time of matter-radiation equality, resulting in a cosmic system where a matter dominance phase followed by an accelerating expansion is allowed.Comment: 7 pages, no figures. Changes in the introduction and main body of the article. Added reference

    A ringed pole-on outflow from DO Tauri revealed by ALMA

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    We present new ALMA Band 6 observations including the CO (2-1) line and 1.3 mmcontinuum emission from the surroundings of the young stellar object DO Tauri. TheALMA CO molecular data show three different series of rings at different radial ve-locities. These rings have radii around 220 au and 800 au. We make individual fits tothe rings and note that their centers are aligned with DO Tauri and its optical high-velocity jet. In addition, we notice that the velocity of these structures increases withthe separation from the young star. We discuss the data under the hypothesis that therings represent velocity cuts through three outflowing shells that are possibly drivenby a wide-angle wind, dragging the environment material along a direction close to theline of sight (i= 19◦). We estimate the dynamical ages, the mass, the momentum andthe energy of each individual outflow shell and those of the whole outflow. The resultsare in agreement with those found in outflows from Class II sources. We make a roughestimate for the size of the jet/wind launching region, which needs to be of.15 au.We report the physical characteristics of DO Tauri?s disk continuum emission (almostface-on and with a projected major axis in the north-south direction) and its velocitygradient orientation (north-south), indicative of disk rotation for a 1-2 Mcentral star.Finally we show an HST [SII] image of the optical jet and report a measurement of itsorientation in the plane of the sky.Fil: Fernandez Lopez, Manuel. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Argentino de Radioastronomía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Argentino de Radioastronomía; ArgentinaFil: Zapata Gonzalez, Luis Alberto. Universidad Nacional Autonoma de Mexico. Instituto de Astronomia; MéxicoFil: Rodríguez, Luis F.. Universidad Nacional Autonoma de Mexico. Instituto de Astronomia; MéxicoFil: Vazzano, María Mercedes. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Argentino de Radioastronomía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Argentino de Radioastronomía; ArgentinaFil: Guzman, Andrés E.. National Astronomical Observatory Of Japan; JapónFil: López, Rosario. Universidad Autónoma de Barcelona. Facultad de Física. Departamento Astronomía y Meteorología; Españ

    Language and cultural awareness of a non-native ESP teacher

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    Introduction. The relation between culture and language is a central issue in foreign language teaching and research where the need to give cultural content the same value as language content and language skills has been stressed. However, conceptualization of teacher language awareness, by focusing largely on formal aspects of language, largely neglects culture as a component of teacher cognition. This paper expands the category of ESP-teacher language awareness suggesting the inclusion of cultural awareness as a separate component of teacher cognition. This concept extension actualizes ESP teaching in the situation shaped by unprecedented mobility and intercultural contacts. Materials and Methods. The historic-logical method was used to determine shortcomings of pedagogical experience and the need to teach culture in ESP. Grounded theory, as an inductive methodology, was utilized to generate conceptual expansion theoretically tied with research in medical and business communication as well as with data on population movement and international scientific cooperation. Results. We defined ESP-cultural knowledge as a system comprising the permanent (know-that) and temporary (know-of) cultural manifestations in a society as well as how they are manifested through language (know-how). That system practical representation is exemplified in medicine and business English discourse. The study expands the structure of ESP-TLA, claiming the focus on cultural awareness as part of ESP discourse which fosters cultural-response education. Discussion and Conclusion. Such claim is pertinent to practitioners involved in the tourism industry, health care, economics, and academic activities such as research and development. This paper is relevant for teachers of English for Specific purposes in the fields mentioned above as well as for researchers engaged in analyzing the problems and methods of teaching a foreign language. However, because of the multiple manifestations and complexity of student motivation to get ESP course, the paper acknowledges the difficulties in addressing cultural content salient to all students in class, an aspect meriting further research. © 2019 National Research Ogarev Mordovia State University. All rights reserved.This research was financially supported by the Russian Foundation for Basic Research (Grant No. 17-29-09136/18 «Multilingualism in the era of post-literacy: Philosophical and cultural studies and methodological and pedagogical development of a multilingual education model»).Российский Фонд Фундаментальных Исследований (РФФИ): 17-29-09136/1

    Estimación de la humedad de tapones de corcho mediante medida de la resistencia electrica

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    En este trabajo se exponen los resultados obtenidos en el Departamento de Productos Forestales del CIFOR-INIA sobre la relación entre la resistencia eléctrica y el contenido de humedad de los tapones de corcho. Estos resultados muestran que los medidores de humedad utilizados habitualmente en la industria pueden alcanzar una precisión elevada, siempre y cuando se tenga en cuenta la influencia de los distintos factores que afectan a la relación resistencia eléctrica-humedad: tipo de tapón, dirección de la medida, temperatura del material. Además, se han obtenido los modelos matemáticos que permiten la calibración de cualquier aparato de este tipo de manera rápida y sencill

    Holographic kinetic k-essence model

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    We consider a connection between the holographic dark energy density and the kinetic k-essence energy density in a flat FRW universe. With the choice c1c\geq1, the holographic dark energy can be described by a kinetic k-essence scalar field in a certain way. In this paper we show this kinetic k-essential description of the holographic dark energy with c1c\geq1 and reconstruct the kinetic k-essence function F(X).Comment: 6 pages, 4 figures, revised version, accepted for publication in Phys.Lett.
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