Three decades ago, Ted Jacobson surprised us with a very appealing approach to General Relativity. According to his proposal, the gravitational field equations are the consequence of the first law of thermodynamics applied to a Rindler observer. Together with the dynamical laws of the black holes, Jacobson’s approach has become a very strong piece of evidence supporting the intimate...
Building upon our previous analysis, which explored the connection between the assembly histories of galaxies and their host dark matter haloes using galaxies with stellar masses in the range $10^{9} \leq M_\star[h^{-1}M_\odot] \leq 10^{11.5}$ from \textit{the Next Generation Illustris} simulations (IllustrisTNG), our study employed the Mutual Information (MI) statistic to quantify the degree...
Aun cuando la estructura e interpretación de las teorías de gravedad y electromagnetismo son muy diferentes, desde un principio, la ley de gravitación de Newton y la ley de Coulomb motivaron la investigación de analogías entre ambas teorías. Si bien se lograron algunos avances en la gravedad Newtoniana, fue en el marco de la relatividad general donde Einstein, Lense y Thirring exploraron una...
The $\Lambda$CDM model is well known and widely accepted in cosmology because of its capability to effectively describe the observed phenomena at large scales. Examples of this is the explanation of the accelerated expansion and the abundance of the primordial light elements. However, with the improvement of astronomical data, a significant tension for the current Hubble parameter has been...
En los últimos años ha surgido una nueva perspectiva para estudiar la evolución del universo, conocida como la conjetura de la gravedad termodinámica. En este trabajo se analiza cómo la primera ley de la termodinámica, aplicada al horizonte aparente del universo, permite derivar ecuaciones de Friedmann modificadas a partir de distintas formulaciones de la entropía del horizonte, en particular...
We study the well-posed 1+1 evolution of self-interacting SU(2) vector fields minimally coupled to gravity within the framework of the 't Hooft-Polyakov magnetic monopole configuration in an astrophysical context. We found a counterexample in which self-interacting vector fields retain a well-posed initial value problem formulation. Also the stability of the black hole solution wih non abelian...
This talk presents a summary of ongoing research projects developed in collaboration with professors from Universidad del Valle and other institutions. These works explore the cosmological implications of extended gravity and dark energy models across different dynamical regimes—from the background level to linear perturbations and nonlinear N-body simulations. Specifically, we study: (i) the...
En este trabajo se utiliza el catálogo Quaia, una de las muestras más limpias y completas de cuásares disponibles hasta la fecha, para estudiar la estructura a gran escala del universo en el entorno de la Vía Láctea. Se trabajó con dos subconjuntos limitados por magnitud (G<20.5 y G<20.0), aplicando procedimientos de limpieza sobre el corrimiento al rojo para mitigar la presencia de valores...
Large-scale structures in the universe can be studied through N bodies interacting gravitationally. In this work, we approximate this process using a quantum dust fluid in one spatial dimension, described by the Schrödinger-Poisson equations. The temporal evolution of the system is calculated using B-splines within the Crank-Nicolson propagator implemented in a predictor-corrector scheme....
In the $\Lambda$CDM framework, the Universe appears homogeneous and isotropic on large scales. However, on scales below $\sim100 \,Mpc$, the matter distribution reveals a hierarchical pattern known as the cosmic web — an interconnected filamentary network that naturally emerges from the anisotropic gravitational collapse of the density field, driven by tidal forces that induce directional...
Modern spectroscopic surveys operate at a scale where cosmological inference benefits from both statistical precision and wide coverage. The Dark Energy Spectroscopic Instrument (DESI) is mapping the large-scale structure of the Universe through high-throughput multi-object spectroscopy, assembling tens of millions of galaxy and quasar spectra across a redshift range from $z \sim 0$ to $z \sim...
Spatial curvature has recently gained renewed attention in quintessence models, as it offers a potential route to reconcile low-energy effective theories with realizations consistent with quantum gravity. On the other hand, multifield scenarios with non-geodesic or spinning trajectories have also proven relevant in this context, allowing for slow-roll regimes even in the presence of steep...
Recientemente el aumento en la detección de señales transitorias de ondas gravita-
cionales(OG) emitidas por las coalescencias de sistemas binarios compactos (CBC)
por parte de los interferómetros gravitacionales ha impulsado el desarrollo e imple-
mentación de diferentes técnicas estadísticas y ofrece una forma independiente de
mejorar la precisión en la inferencia de los parámetros de...
In this work, we study the number density of Lyman Alpha Emitter (LAE) galaxies, their physical properties, and synthetic spectra at redshift ~ 6 using high-resolution hydrodynamical simulations with radiative transfer from the Thesan project. By recreating the scenario described in Becker et al. 2018, we test the hypothesis that observations to date are missing the vast majority of the...
Cosmological perturbation theory provides the fundamental framework for describing the evolution of the matter-energy density field in an expanding universe and serves as the basis for understanding the formation of large-scale structures within the $\Lambda$CDM paradigm. In this work, we present an analytical approach to describe the evolution of fluctuations—small deviations from the mean...
La red cósmica suele describirse en términos de filamentos, vacíos, nudos y láminas. Estudiarla permite caracterizar su morfología y profundizar en la estructura a gran escala del Universo, lo cual resulta fundamental para acotar parámetros cosmológicos como la materia oscura, la energía oscura y la geometría del Universo. La distribución y propiedades de sus componentes responden de forma...
El Dark Energy Spectroscopic Instrument (DESI) está revolucionando la cosmología observacional mediante el mapeo de decenas de millones de espectros de galaxias y cuásares a través de 14,000 grados cuadrados y un rango de redshift de z ~ 0 a z ~ 3.5. Con un volumen muestreado de aproximadamente 20 Gpc³, DESI ofrece una oportunidad sin precedentes para estudiar la estructura a gran escala del...
En la última década, los vacíos cósmicos se han consolidado como uno de los trazadores más prometedores para obtener pruebas cosmológicas independientes y sensibles a la energía oscura. Su estudio, junto con el de los filamentos y demás componentes de la red cósmica, permite explorar la estructura a gran escala del Universo más allá de los análisis basados en la función de correlación de dos...
Se investiga la estructura de estrellas de neutrones en el marco de una teoría escalar-tensorial axiónica. El modelo se define por un acoplamiento no mínimo entre el campo de axión y la curvatura, descrito por la función $f(\phi)=1+\xi\phi^2$, y se analiza en el régimen cosmológico post-inflacionario, donde el axión oscila en torno al mínimo de su potencial. Se derivan las ecuaciones de...
The profound connection between gravity and thermodynamics has been firmly established since Jacobson’s seminal result, where the Einstein field equations were derived from the Bekenstein–Hawking entropy–area relation under the assumption of local thermodynamic equilibrium on local Rindler horizons. Deviations from this entropy law necessarily induce non-equilibrium corrections, as illustrated...
Large modern spectroscopic surveys require robust quality-control systems that operate at the scale of millions of observations. The Dark Energy Spectroscopic Instrument (DESI) maps the large-scale structure of the Universe through multi-object spectroscopy at unprecedented speed, collecting tens of millions of spectra every year from galaxies and quasars. Efficiently identifying anomalies in...
Quasars are among the most luminous and distant sources in the Universe, offering great potential as standard candles for cosmology. However, the diversity in their spectral energy distributions (SEDs) and the dependence of luminosity on physical parameters introduce significant challenges. In this work, we present a statistical analysis of quasar luminosities across multiple spectral bands,...
