Desarrollo de una presentación interactiva y multimedia orientada a la docencia del análisis cinemático del Movimiento Armónico Simple

Nowadays, computers suppose a great potential as complementary didactic tool to traditional means of education. For that reason, the advantage of this potential is considered by the work group, creating interactive and multimedia presentations oriented to facilitate teaching of different physics fields. In particular, the objective of this work is the design of a presentation oriented to teaching kinematical aspects of the simple harmonic movement. Given the dynamic nature of the subject, it is evident the adventages that suppose an animated presentation which it helps the student to understand the kinematical magnitudes. This tool will be very useful to the professor as complement of theoretical classes, and available to the students in the reinforcement of the knowledge.Es evidente el gran potencial que el ordenador supone como herramienta didáctica complementaria a los medios de enseñanza tradicionales. Es por ello que el grupo de trabajo se plantea el aprovechamiento de este potencial, creando presentaciones interactivas y multimedia orientadas a la docencia en los distintos campos de la física.En concreto, en este trabajo se plantea el diseño de una presentación orientada a la docencia de los aspectos cinemáticas del movimiento armónico simple. Dada la naturaleza dinámica del tema en cuestión, es evidente las ventajas que supone disponer de una presentación animada del mismo que ayude al alumno a entender la magnitudes cinemáticas implicadas, herramientas de gran utilidad para el profesor como complemento de sus clases teóricas, y disponible para alumnos de ayuda en el afianzamiento de los conocimientos

Quintessence and Scalar Dark Matter in the Universe

Continuing with previous works, we present a cosmological model in which dark matter and dark energy are modeled by scalar fields $\Phi$ and $\Psi$, respectively, endowed with the scalar potentials $V(\Phi)=V_{o}[ \cosh {(\lambda \sqrt{\kappa_{o}}\Phi)}-1]$ and $\tilde{V}(\Psi)=\tilde{V_{o}}[ \sinh {(\alpha \sqrt{\kappa_{o}}\Psi)}] ^{\beta}$. This model contains 95% of scalar field. We obtain that the scalar dark matter mass is $m_{\Phi}\sim 10^{-26}eV.$ The solution obtained allows us to recover the success of the standard CDM. The implications on the formation of structure are reviewed. We obtain that the minimal cutoff radio for this model is $r_{c}\sim 1.2 kpc.$Comment: 4 pages REVTeX, 3 eps color figures. Minor changes and references updated. To appear in Classical and Quantum Gravity as a Letter to the Editor. More information at http://www.fis.cinvestav.mx/~siddh/PHI

Scalar Field as Dark Matter in the Universe

We investigate the hypothesis that the scalar field is the dark matter and the dark energy in the Cosmos, wich comprises about 95% of the matter of the Universe. We show that this hypothesis explains quite well the recent observations on type Ia supernovae.Comment: 4 pages REVTeX, 1 eps figure. Minor changes. To appear in Classical and Quantum Gravit

Kneeling ability after total knee replacement

Kneeling ability is consistently the poorest patient-rated outcome after total knee replacement (TKR), with 60–80% of patients reporting difficulty kneeling or an inability to kneel. Difficulty kneeling impacts on many activities and areas of life, including activities of daily living, self-care, leisure and social activities, religious activities, employment and getting up after a fall. Given the wide range of activities that involve kneeling, and the expectation that this will be improved with surgery, problems kneeling after TKR are a source of dissatisfaction and disappointment for many patients. Research has found that there is no association between range of motion and self-reported kneeling ability. More research is needed to understand if and how surgical factors contribute to difficulty kneeling after TKR. Discrepancies between patients’ self-reported ability to kneel and observed ability suggests that patients can kneel but elect not to. Reasons for this are multifactorial, including knee pain/discomfort, numbness, fear of harming the prosthesis, co-morbidities and recommendations from health professionals. There is currently no evidence that there is any clinical reason why patients should not kneel on their replaced knee, and reasons for not kneeling could be addressed through education and rehabilitation. There has been little research to evaluate the provision of healthcare services and interventions for patients who find kneeling problematic after TKR. Increased clinical awareness of this poor outcome and research to inform the provision of services is needed to improtzve patient care and allow patients to return to this important activity

A Further Analysis of a Cosmological Model of Quintessence and Scalar Dark Matter

We present the complete solution to a 95% scalar field cosmological model in which the dark matter is modeled by a scalar field $\Phi$ with the scalar potential $V(\Phi)=V_{o}[ \cosh {(\lambda \sqrt{\kappa_{o}}\Phi)}-1]$ and the dark energy is modeled by a scalar field $\Psi$, endowed with the scalar potential $\tilde{V}(\Psi)=\tilde{V_{o}}[ \sinh {(\alpha \sqrt{\kappa_{o}}\Psi)}] ^{\beta}$. This model has only two free parameters, $\lambda$ and the equation of state $\omega_{\Psi}$. With these potentials, the fine tuning and the cosmic coincidence problems are ameliorated for both dark matter and dark energy and the models agrees with astronomical observations. For the scalar dark matter, we clarify the meaning of a scalar Jeans lenght and then the model predicts a suppression of the Mass Power Spectrum for small scales having a wave number $k > k_{min,\Phi}$, where $k_{min,\Phi} \simeq 4.5 h {\rm Mpc}^{-1}$ for $\lambda \simeq 20.28$. This last fact could help to explain the dearth of dwarf galaxies and the smoothness of galaxy core halos. From this, all parameters of the scalar dark matter potential are completely determined. The dark matter consists of an ultra-light particle, whose mass is $m_{\Phi} \simeq 1.1\times 10^{-23} {\rm eV}$ and all the success of the standard cold dark matter model is recovered. This implies that a scalar field could also be a good candidate as the dark matter of the Universe.Comment: 11 pages REVTeX, 6 eps color figures. More information at http://www.fis.cinvestav.mx/~siddh/PHI/. Revised version. New results added and changes made in response to referee comment

Dynamical Boson Stars

The idea of stable, localized bundles of energy has strong appeal as a model for particles. In the 1950s John Wheeler envisioned such bundles as smooth configurations of electromagnetic energy that he called {\em geons}, but none were found. Instead, particle-like solutions were found in the late 1960s with the addition of a scalar field, and these were given the name {\em boson stars}. Since then, boson stars find use in a wide variety of models as sources of dark matter, as black hole mimickers, in simple models of binary systems, and as a tool in finding black holes in higher dimensions with only a single killing vector. We discuss important varieties of boson stars, their dynamic properties, and some of their uses, concentrating on recent efforts.Comment: 79 pages, 25 figures, invited review for Living Reviews in Relativity; major revision in 201

HAWC and Fermi-LAT Detection of Extended Emission from the Unidentified Source 2HWC J2006+341

The discovery of the TeV point source 2HWC J2006+341 was reported in the second HAWC gamma-ray catalog. We present a follow-up study of this source here. The TeV emission is best described by an extended source with a soft spectrum. At GeV energies, an extended source is significantly detected in Fermi-LAT data. The matching locations, sizes and spectra suggest that both gamma-ray detections correspond to the same source. Different scenarios for the origin of the emission are considered and we rule out an association to the pulsar PSR J2004+3429 due to extreme energetics required, if located at a distance of 10.8 kpc.Comment: 12 pages, 2 figures. To appear in ApJ

A Contribution of the HAWC Observatory to the TeV era in the High Energy Gamma-Ray Astrophysics: The case of the TeV-Halos

We present a short overview of the TeV-Halos objects as a discovery and a relevant contribution of the High Altitude Water \v{C}erenkov (HAWC) observatory to TeV astrophysics. We discuss history, discovery, knowledge, and the next step through a new and more detailed analysis than the original study in 2017. TeV-Halos will contribute to resolving the problem of the local positron excess observed on the Earth. To clarify the latter, understanding the diffusion process is mandatory.Comment: Work presented in the 21st International Symposium on Very High Energy Cosmic Ray Interactions(ISVHECRI 2022) as part of the Ph. D. Thesis of Ramiro Torres-Escobedo (SJTU, Shanghai, China). Accepted for publication in SciPost Physics Proceedings (ISSN 2666-4003). 11 pages, 3 Figures. Short overview of HAWC and TeV Halos objects until 202