A5078820825- Cosmology and Gravitation Theories
- Black Holes and Theoretical Physics
- Galaxies: Formation, Evolution, Phenomena
- Dark Matter and Cosmic Phenomena
- Relativity and Gravitational Theory
- Noncommutative and Quantum Gravity Theories
- Geophysics and Gravity Measurements
- Pulsars and Gravitational Waves Research
- Solar and Space Plasma Dynamics
- Advanced Thermodynamics and Statistical Mechanics
- Astronomy and Astrophysical Research
- Quantum Mechanics and Applications
- Quantum Electrodynamics and Casimir Effect
- Particle physics theoretical and experimental studies
- Scientific Research and Discoveries
- Gamma-ray bursts and supernovae
- Cold Atom Physics and Bose-Einstein Condensates
- Geophysics and Sensor Technology
- COVID-19 epidemiological studies
- Stochastic processes and financial applications
- Astro and Planetary Science
- Fluid Dynamics Simulations and Interactions
- Astrophysical Phenomena and Observations
- Mathematical and Theoretical Epidemiology and Ecology Models
- Astrophysics and Cosmic Phenomena
Universidad de Guanajuato
2015-2024
Universidad de León
2021
Autonomous University of Chiapas
2010-2021
Consejo Nacional de Humanidades, Ciencias y Tecnologías
2017
UK Astronomy Technology Centre
2015
University of Edinburgh
2015
Royal Observatory
2015
Instituto Politécnico Nacional
2000-2011
Universidad Michoacana de San Nicolás de Hidalgo
2010
Center for Research and Advanced Studies of the National Polytechnic Institute
2000-2010
The grand challenges of contemporary fundamental physics---dark matter, dark energy, vacuum inflation and early universe cosmology, singularities the hierarchy problem---all involve gravity as a key component. And all gravitational phenomena, black holes stand out in their elegant simplicity, while harbouring some most remarkable predictions General Relativity: event horizons, ergoregions. hitherto invisible landscape Universe is being unveiled before our eyes: historical direct detection...
The Scalar Field Dark Matter model has been known in various ways throughout its history; Fuzzy, BEC, Wave, Ultralight, Axion-like Matter, etc. All of them consist proposing that dark matter the universe is a spinless field Φ follows Klein-Gordon (KG) equation motion □Φ − dV / d = 0, for given scalar potential V . difference between different models sometimes choice In literature we find people usually work non-relativistic, weak-field limit equation, where it transforms into Schrödinger and...
We present the complete solution to a $95%$ scalar field cosmological model in which dark matter is modeled by $\ensuremath{\Phi}$ with potential $V(\ensuremath{\Phi}{)=V}_{0}[\mathrm{cosh}(\ensuremath{\lambda}\sqrt{{\ensuremath{\kappa}}_{0}}\ensuremath{\Phi})\ensuremath{-}1]$ and energy \ensuremath{\Psi}, endowed $\stackrel{\ifmmode \tilde{}\else...
Dark energy and dark matter are only indirectly measured via their gravitational effects. It is possible that there an exchange of within the sector, this offers interesting alternative approach to coincidence problem. We consider two broad classes interacting models where a linear combination sector densities. The first class has been previously investigated, but we define new variables find exact solution, which allows for more direct, transparent, comprehensive analysis. second not...
Using numerical techniques, we study the collapse of a scalar field configuration in Newtonian limit spherically symmetric Einstein-Klein-Gordon system, which results so called Schr\"odinger-Newton (SN) set equations. We present code developed to evolve SN system and related topics, like equilibrium configurations boundary conditions. Also, analyze evolution different initial physical quantities associated with them. In particular, readdress issue gravitational cooling mechanism for systems...
It has been suggested that the internal dynamics of dwarf spheroidal galaxies (dSphs) can be used to test whether or not ultralight axions with ma ∼ 10−22 eV are a preferred dark matter candidate. However, comparisons theoretical predictions tend inconclusive for simple reason while most cosmological models consider only matter, one observes baryons. Here, we use realistic kinematic mock data catalogues Milky Way (MW) dSph's show 'mass–anisotropy degeneracy' in Jeans equations leads biased...
The existence of dark matter in the Universe has been solidly established last decades, after arrival accurate cosmological and astrophysical observations, some consider it most challenging problem modern physics. Given magnitude problem, one cannot discard new particles with properties that may look exotic comparison our current understanding ordinary matter. This is case for so-called scalar field model, which assumes a (probably fundamental) very tiny mass can have observable consequences...
Continuing with previous works, we present a cosmological model in which dark matter and energy are modeled by scalar fields $\Phi $ $\Psi$, respectively, endowed the potentials $V(\Phi)=V_{o}[ \cosh {(\lambda \sqrt{\kappa_{o}}\Phi)}-1] $\tilde{V}(\Psi)=\tilde{V_{o}}[ \sinh {(\alpha \sqrt{\kappa_{o}}\Psi)}] ^{\beta}$. This contains 95% of field. We obtain that mass is $m_{\Phi}\sim 10^{-26}eV.$ The solution obtained allows us to recover success standard CDM. implications on formation...
In this paper we propose a quintessence model with the potential $V(\ensuremath{\Phi}{)=V}_{0}[\mathrm{sinh}(\ensuremath{\alpha}\sqrt{{\ensuremath{\kappa}}_{0}}\ensuremath{\Delta}\ensuremath{\Phi}){]}^{\ensuremath{\beta}}$ $\ensuremath{\beta}<0,$ whose asymptotic behavior corresponds to an inverse power-law at early times and exponential one late times. We demonstrate that is tracker solution it could have driven Universe into its current inflationary stage. The exact solutions description...
Equilibrium configurations for a self-gravitating scalar field with self-interaction are constructed. The corresponding Schr\"odinger-Poisson (SP) system is solved using finite differences assuming spherical symmetry. It shown that equilibrium of the SP late-time attractor solutions initially quite arbitrary density profiles, which relax and virialize through emission bursts; process dubbed gravitational cooling. Among other potential applications, these results indicate dark matter models...
In this paper, we develop a Newtonian approach to the collapse of galaxy fluctuations scalar field dark matter under initial conditions inferred from simple assumptions. The full relativistic system, so-called Einstein-Klein-Gordon is reduced Schr\"odinger-Newton one in weak-field limit. scaling symmetries SN equations are exploited track nonlinear single fluctuations. results can be applied both real and complex fields.
We consider the conditions needed to unify description of dark matter, energy, and inflation in context string landscape. find that incomplete decay inflaton field gives possibility a single is responsible for all three phenomena. By contrast, unifying matter energy into field, separate from inflaton, appears rather difficult.
We study in detail the properties of gravitationally bounded multistate configurations, made spin-zero bosons, Newtonian regime. show that such particular, their stability, depend upon how particles are distributed different states they composed of. Numerical techniques used to distinguish between stable and unstable solutions, determine final configurations evolve towards. Multistate equilibrium could be as models galactic halos scalar field dark matter, whose rotation curves appear more...
Compact objects, like neutron stars and white dwarfs, may accrete dark matter, then be sensitive probes of its presence. These compact with a matter component can modeled by perfect fluid minimally coupled to complex scalar field (representing bosonic component), resulting in objects known as fermion-boson stars. We have performed the dynamical evolution these order analyze their stability, study spectrum normal modes, which reveal amount system. Their stability analysis shows structure...
Nonlinearities in a realistic axion field potential may play an important role the cosmological dynamics. In this paper we use Boltzmann code CLASS to solve background and linear perturbations evolution of contrast our results with those CDM free case. We conclude that there is slight delay onset oscillations when nonlinearities are taken into account. Besides, identify tachyonic instability modes resulting presence bump power spectrum at small scales. Some comments turn about true source...
We study the dynamical properties of tracker quintessence models using a general parametrization their corresponding potentials, and show that there is condition for appearance behavior at early times. Likewise, we determine conditions under which can also provide an accelerating expansion universe with equation state closer to $\ensuremath{-}1$. Apart from analysis background dynamics, include linear density perturbations field in consistent manner same potential, influence they have on...
We investigate the hypothesis that scalar field is dark matter and energy in cosmos, which comprises about 95% of Universe. show this explains quite well recent observations on type Ia supernovae.
The dynamics of a cosmological model fueled by scalar field dark matter with cosh-like potential plus constant is investigated in detail. It revealed that the late-time attractor always de Sitter solution, and that, depending on values free parameters, oscillating solution -- modeling cold mediates between some early stage (say, radiation-dominated solution) accelerating attractor.
As we are entering the era of precision cosmology, it is necessary to count on accurate cosmological predictions from any proposed model dark matter. In this paper present a novel approach evolution scalar fields that eases their analytic and numerical analysis at background linear order perturbations. The new method makes use appropriate angular variables simplify writing equations motion, which also show usual field play secondary role in dynamics. We apply endowed with quadratic potential...
Fermion-boson stars are solutions of the gravitationally coupled Einstein-Klein-Gordon-hydrodynamic equations system. By means methods developed in previous works, we perform a stability analysis fermion-boson that include quartic self-interaction their bosonic part. Additionally, describe complete structure and instability regions space free parameters, which argue is qualitatively same for any value self-interaction. The relationship between total mass mixed general also discussed terms...
ABSTRACT We investigate the ability of human ‘expert’ classifiers to identify strong gravitational lens candidates in Dark Energy Survey like imaging. recruited a total 55 people that completed more than 25 per cent project. During classification task, we present participants 1489 images. The sample contains variety data including simulations, real lenses, non-lens examples, and unlabelled data. find experts are extremely good at finding bright, well-resolved Einstein rings, while arcs with...
The curvaton was introduced recently as a distinct inflationary mechanism for generating adiabatic density perturbations. Implicit in that scenario is the offers new reheating after inflation, it form of energy not diluted by expansion. We consider context braneworld inflation model, steep which features novel use to give ending inflation. original model featured gravitational particle production, but inefficiency process causes observational difficulties. demonstrate here phenomenology much...
A unified model is developed within the context of braneworld paradigm, where a single scalar field can act as both inflaton in very early universe and also strong, self-interacting dark matter post-inflationary universe. Reheating proceeds due to overproduction subsequent evaporation primordial black holes. Observational constraints, most notably from gravitational waves, are satisfied if probability PBH formation sufficiently high.
We construct an explicit scenario whereby the same material driving inflation in early universe can comprise dark matter present universe, using a simple quadratic potential. Following and preheating, density of inflaton/dark particles is reduced to observed level by period thermal inflation, duration already invoked literature for other reasons. Within context string landscape, one further argue nonzero vacuum energy this field, thus unifying matter, into single fundamental field.
Extra dimensions provide a very useful tool in addressing number of the fundamental problems faced by Standard Model. The following provides basic introduction to this broad subject area as given at VIII School Gravitational and Mathematical Physics Division Mexican Physical Society December 2009. Some prospects for extra dimensional searches 7 TeV LHC with $\sim$1 $fb^{-1}$ integrated luminosity are provided.