As gravitation and electromagnetism are closely analogous long-range interactions, and the current formulation of gravitation is given in terms of geometry, we expect the latter also to appear through the geometry. This unification has however, remained an unfulfilled goal. Thence emerges a relativistic theory of the asymmetric field by generalization of the general relativity. It will demonstrate in a new way that the field-equations chosen for the non-symmetric fields are really the natural ones.

As gravitation and electromagnetism are closely analogous long-range interactions, and the current formulation of gravitation is given in terms of geometry. Thence emerges a relativistic theory of the field by generalization of the general relativity. The derivation presented shows how naturally we can extend general relativity theory to a non-symmetric field, and that the field-equations are really the generalizations of the gravitational equations. With curvature tensor and the variational principle, we will deduce the field equations and Bianchi's identities. In consecuense, the field equations will find from Bianchi's identities.

As gravitation and electromagnetism are closely analogous long-range interactions, and the current formulation of gravitation is given in terms of geometry, we expect the latter also to appear throug the geometry. We look for the formally most simple expression for the law of gravitation in the absence of an electromagnetic field, and then the most natural generalization of this law. This theory contain Maxwell theory in first approximation. In the following we outline the scheme of the general theory and then show in which sense this contains the law of the pure gravitational field and Maxwell theory.

Lately the Cosmic Background Radiation (CMB) data have resulted in anomalies or deviations with respect to the standard model of cosmology, which has led several cosmologists to consider alternative models to the standard model (homogeneous and isotropic), such as the Bianchi models, which are homogeneous but anisotropic. Based on these motivations to consider alternative models, we propose to study, in the present work, the algebraic classification of the Bianchi models and each of the Bianchi space-times, applying the ADM formalism of general relativity in its Hamiltonian version and the groups G3 . The dynamic equations are shown with the help of the Hamiltonian density H and the Poisson parentheses, in other words, the equations of motion are presented for each of the Bianchi space-times. Some theoretical consequences of these equations are discussed when we take the limit Ω → -�...

In this paper, we have given a presentation of the relativistic theory of asymmetric field. It is our aim to present a theory of gravitation and electomagnetism by a generalization of the concepts and mathematical methods of the general relativity. We look for the formally most simple expression for the law of gravitation in the absence of an electromagnetic field, and then the most natural generalization of this law. This theory contain  Maxwell's theory in the Lambda transformation.

The last few decades have seen an explosive increase in the amount and precision of data obtained from cosmological observations. Theoretical cosmologists have not yet finished interpreting this amount of data. Likewise, the wonderful ideas we have for the beginning of the Universe have not yet been connected with concrete models of elementary particles. Currently, the existence of dark matter (DM) is accepted in the scientific community. Stars, planets, comets, cosmic dust and other forms of matter make up 5% of the matter in the Universe. The remaining 95% would be "dark matter" and "dark energy", if it is that, it is not known what it is, in fact they exist. In this work, the standard cosmological model is studied, as well as the production of relic particles with the Boltzmann equation applied to the decoupling of relic particles from a reservoir.

In writing out the eq. (36)  in my recent paper [1], an inadvertent error led to two errant numerical expressions in equations (37) and (38) that propagated to the “Field equations”. The main results and conclusions of my paper remain unchanged. All of the affected formulas are corrected below.

In writing out the equations in section of Hamilton principle in my recent paper [1], inadvertents errors led to errant numerical expressions in “Field equations”. The main results and conclusions of my paper remain unchanged. All of the affected formulas are corrected below.

In this work, we present the fundamentals of the general theory of relativity, the standard cosmology and a description of current and interesting research topics about our current Universe, in addition the emergence of the dark matter problem has been raised, trying to outline possible dark matter candidates. This assumption seems realistic, however the analysis, from the point of view of standard cosmology, which is also studied in this work, turns out to be more complex than if dark matter were considered with a single species of elementary particle.

Observations on the anisotropies of the Cosmic Microwave Background (CMB) have become a fundamental tool in Cosmology. We present a brief description of the mformalism necessary to understand the evolution of the anisotropies, and how their power spectrum gives us information about the evolution and composition of the universe.

Modified Newtonian dynamics (MOND) is a hypothesis that proposes a modification of Newton's law of universal gravitation to account for observed properties of galaxies. This theory is an alternative to the hypothesis of dark matter in terms of explaining why galaxies do not appear to obey the currently understood laws of physics. In this work, we present a relativistic theory of gravitation for MOND.

In this article, we present the fundamentals of Goldstone's theorem and the breaking of global symmetries. As well as one of the important aspects to take into account in the process of spontaneous symmetry breaking are the possible topological defects generated by the breaking. For this reason, we will expose the concept of topological defect and the calculation of the relic density of the axion, considered as a candidate to dark matter.

In writing out the eq. (43) for in my recent paper [1], an inadvertent error led to two errant numerical expressions in “Diferential identities”. The main results and conclusions of my paper remain unchanged. All of the affected formulas are corrected below.

This work has three important purposes: first it is the study of Markov Chains, the second is to show that Markov chains have different applications and finally it is to model a process of this behaves. Throughout this work we will describe what a Markov chain is, what these processes are for and how these chains are classified. We will describe a Markov Chain, that is, analyze what are the primary elements that make up a Markov chain, among others.

Fourier analysis is currently one of the important parts of mathematical analysis. Fourier analysis methods are used in physics, electrical engineering, and other sciences to solve various problems. In this article we will give the main concepts of Fourier analysis and its applications in spectral analysis in solving problems using R, as shown in the examples.