Non perturbative regularization of one loop integrals at finite temperature

A method devised by the author is used to calculate analytical expressions for one loop integrals at finite temperature. A non-perturbative regularization of the integrals is performed, yielding expressions of non-polynomial nature. A comparison with previuosly published results is presented and the advantages of the present technique are discussed.Comment: 7 pages, 2 figures, 2 tables; corrected some typos and simplified eq. (8

Petrological study of sorne dark inclusions in hercynian granitoids frorn the Hesperian Massif (Spain)

[Resumen] Se estudian algunos enclaves de origen ígneo incluidos en granitoides hercínicos sincinemáticos meso y catazonales situados en la zona Centroibérica. Esta serie de rocas así como otras similares situadas en áreas próximas, y estudiadas por diversos autores, presentan un notable grado de variabilidad composicional, encontrándose desde tipos fuertemente metaalumínicos a otros peralumínicos, e incluso rocas aberrantes fuertemente subsaturadas y con leucita normativa. También se observa, a nivel de afloramiento y microscópico, una fuerte heterogeneidad en las estructuras y en las texturas, debido a la superposici6n de procesos de hibridación y reajustes mineralógicos. Estas transformaciones están además relacionadas en pate con reacciones entre los materiales básicos y los granitoides que las incluyen. En los casos estudiados, la reactividad está realzada por el carácter catazonal de los granitoides, por su riqueza en fase volátil (manifiesta por una considerable proporción de moscovita) y por la imbricación con los procesos metam6rficos regionales y la migmatizaci6n. Por otra parte, se estudian rocas de un pequeño cuerpo plutónico básicJ, intrusivo en un conjunto de metasedimentos de grado medio-alto, próximos a un área de intensa migmatización, y que por sus características pueden corresponderse con algunos de los enclaves básicos incluidos en los granitoides migmáticos inhomogéneos.[Abstract] Several dark inclusions of igneous origin from synkinematic meso and catazonal Hercynian granitoids of the Central Iberian Zone are studied. The rocks of this group of inclusions and of similar ones outcropping in adyacent areas, which have been studied by various authors, showa remarkable degree of compositional variability. They range from strongly meta-aluminous to peraluminous types and even unusual undersaturated rocks or rocks with normative leucite· are known to exist among them. Hybridization processes, together with mineralogical readjus~ments, resulted in a marked textural and structural heterogeneity of the rocks at the scale of an outcrop or under the microscope. Part of these transformations can be related to interaction between the basic material of the inclusions and the enclosing granitoids. In the cases studied, reactivity was enhanced by the catazonal character of the granitoids, their richness in volatiles (as indicated by their considerable amount of muscovite) and their involvment in processes of regional metamorphism and migmatization. The rocks of a small plutonic outcrop intrusive in medium to high grade metasediments are studied.The chemico-mineralogical characteristics of these rocks suggest that they may be comparable withsorpe of the basic inclusions found in masses of the so-called inhomogeneous migmatitic granitoids

Using the Generic Synteny Browser (GBrowse_syn)

Genome Browsers are software that allow the user to view genome annotations in the context of a reference sequence, such as a chromosome, contig, scaffold, etc. The Generic Genome Browser (GBrowse) is an open-source genome browser package developed as part of the Generic Model Database Project (see UNIT ; Stein et al., 2002). The increasing number of sequenced genomes has led to a corresponding growth in the field of comparative genomics, which requires methods to view and compare multiple genomes. Using the same software framework as GBrowse, the Generic Synteny Browser (GBrowse_syn) allows the comparison of colinear regions of multiple genomes using the familiar GBrowse-style Web page. Like GBrowse, GBrowse_syn can be configured to display any organism, and is currently the synteny browser used for model organisms such as C. elegans (WormBase; http://www.wormbase.org; see UNIT 1.8) and Arabidopsis (TAIR; http://www.arabidopsis.org; see UNIT 1.1). GBrowse_syn is part of the GBrowse software package and can be downloaded from the Web and run on any Unix-like operating system, such as Linux, Solaris, or MacOS X. GBrowse_syn is still under active development. This unit will cover installation and configuration as part of the current stable version of GBrowse (v. 1.71)

A New Methodology for Decision-Making in Buildings Energy Optimization

[Abstract] When designing or retrofitting a building, not too many tools let architects and engineers to define the optimal conditions to reduce energy consumption with the minimal economic investment. This is because different software resources must be employed and an iterative calculation must be done which, most of times, is not possible. The present study aims to define an original methodology that let researchers and architects to select the best option between different possibilities. To reach this objective, Monte Carlo method is employed on the ISO 13790 standard reaching the probability distribution of the energy consumption of each building after each possible modification. From main results, two mathematical models were obtained from a real case study showing the relation between annual energy consumption and economic investment of each different building retrofits. What is more, in disagreement with the expected result, the best retrofit option was not the one with the highest cost and qualities. In conclusion, this methodology can be a useful tool for researchers and professionals to improve their decision-making

Noncommutative spaces, the quantum of time and the Lorentz symmetry

We introduce three space-times that are discrete in time and compatible with the Lorentz symmetry. We show that these spaces are no commutative, with commutation relations similar to the relations of the Snyder and Yang spaces. Furthermore, using a reparametrized relativistic particle we obtain a realization of the Snyder type spaces and we construct an action for them.Comment: 8 pages, to appear in PR

Fermionic Dark Matter: Physics, Astrophysics, and Cosmology

The nature of dark matter (DM) is one of the most relevant questions in modern astrophysics. We present a brief overview of recent results that inquire into a possible fermionic quantum nature of the DM particles, focusing mainly on the interconnection between the microphysics of the neutral fermions {and the macrophysical structure of galactic halos, including their formation both in the linear and non-linear cosmological regimes. We discuss the general relativistic Ruffini-Arg\"uelles-Rueda (RAR) model of fermionic DM in galaxies, its applications to the Milky Way, the possibility that the Galactic center harbors a DM core instead of a supermassive black hole (SMBH), the S-cluster stellar orbits with an in-depth analysis of the S2's orbit including precession, the application of the RAR model to other galaxy types (dwarf, elliptic, big elliptic and galaxy clusters), and universal galaxy relations. All the above focusing on the model parameters constraints, most relevant to the fermion mass. We also connect the RAR model fermions with particle physics DM candidates, self-interactions, and galactic observables constraints. The formation and stability of core-halo galactic structures predicted by the RAR model and their relation to warm DM cosmologies are also treated. Finally, we briefly discuss how gravitational lensing, dynamical friction, and the formation of SMBHs can also probe the DM nature.Comment: Review paper to be published in Universe, Special Issue "Galactic Center with Gravity

Hinting a dark matter nature of Sgr A* via the S-stars

The motion data of the S-stars around the Galactic Centre gathered in the last 28 yr imply that Sgr A* hosts a supermassive compact object of about 4×106M⊙⁠, a result awarded with the Nobel Prize in Physics 2020. A non-rotating black hole (BH) nature of Sgr A* has been uncritically adopted since the S-star orbits agree with Schwarzschild geometry geodesics. The orbit of S2 has served as a test of general relativity predictions such as the gravitational redshift and the relativistic precession. The central BH model is, however, challenged by the G2 post-peripassage motion and by the lack of observations on event-horizon-scale distances robustly pointing to its univocal presence. We have recently shown that the S2 and G2 astrometry data are better fitted by geodesics in the spacetime of a self-gravitating dark matter core–halo distribution of 56 keV-fermions, ‘darkinos’, which also explains the outer halo Galactic rotation curves. This letter confirms and extends this conclusion using the astrometry data of the 17 best-resolved S-stars, thereby strengthening the alternative nature of Sgr A* as a dense core of darkinos.Fil: Becerra Vergara, E. A.. Università di Roma; ItaliaFil: Argüelles, Carlos Raúl. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: Krut, A.. Università di Roma; ItaliaFil: Rueda, J. A.. Università di Roma; ItaliaFil: Ruffini, R.. Università di Roma; Itali

Anisotropic quark stars with an interacting quark equation of state

A deep exploration of the parameter space that relates the interacting equation of state with the bag constant B, and the interaction parameter a, is fundamental for the construction of diverse models of quark stars. In particular, the anisotropy of quark stars with a well-motivated quantum chromodynamics (QCD) equation of state is presented here. The contribution of the fourth order corrections parameter (a4) of the QCD perturbation on the radial and tangential pressure generate significant effects on the mass-radius relation and the stability of the quark star. An adequate set of solutions for several values of the bag factor and the interaction parameter are used in order to calculate the relation between the mass, radius, density, compactness, and consequently the maximum masses and the stability. Therefore, while the more interactive quark solution leads to higher masses, the weak interaction among quarks gives solutions similar to the widely known MIT bag model

Realistic Anisotropic Neutron Stars: Pressure Effects

In this paper, we study the impact of anisotropy on neutron stars with different equations of state, which have been modeled by a piecewise polytropic function with continuous sound speed. Anisotropic pressure in neutron stars is often attributed to interior magnetic fields, rotation, and the presence of exotic matter or condensates. We quantify the presence of anisotropy within the star by assuming a quasi-local relationship. We find that the radial and tangential sound velocities constrain the range of anisotropy allowed within the star. As expected, the anisotropy affects the macroscopic properties of stars, and it can be introduced to reconcile them with astrophysical observations. For instance, the maximum mass of anisotropic neutron stars can be increased by up to 15\% compared to the maximum mass of the corresponding isotropic configuration. This allows neutron stars to reach masses greater than $2.5M_\odot$, which may explain the secondary compact object of the GW190814 event. Additionally, we propose a universal relation for the binding energy of an anisotropic neutron star as a function of the star's compactness and the degree of anisotropy.Comment: 12 pages, 7 figure