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The Large-Scale Structure (LSS) of the Universe provides valuable information for modern cosmology. The future redshift surveys, as DESI (Dark Energy Spectroscopic Instrument), will measure millions of galaxies and quasars, which allows to measure the history expansion and the growth factor. In this work, we present the theoretical model of the matter power spectrum and the redshift space multipoles of the galaxy power spectrum. We compute the spectrum using different methods as 1-loop Standard Perturbation Theory, Effective Field Theory and the Infrarred resummations., Comment: 5 pages, in Spanish, 2 figures; Revista Digital de la RNAFM, vol. 27, Pp. 209-212 (2022)

We live in the golden era of cosmology due to next redshift surveys will map a significant volume of the Universe across a wide range of redshifts. We analyze the clustering of the eBOSS luminous red galaxy sample (eBOSS LRG). We measure the multipole power spectra inferred from the NGC sample (107500 galaxies) and SGC sample (67316 galaxies) between redshifts 0.6 and 1.0, with effective redshift zeff=0.695 and zeff=0.704 for NGC and SGC samples, respectively. We use the non-linear perturbation theory to model the the redshift space multipoles of the galaxy power spectrum., Comment: 4 pages, in Spanish, 4 figures; Revista Digital de la RNAFM, vol. 27, Pp. 213-216 (2022)

Cosmic voids are promising cosmological laboratories for studying the dark energy phenomenon and alternative gravity theories. They are receiving special attention nowadays in view of the new generation of galaxy spectroscopic surveys, which are covering an unprecedented volume and redshift range. There are two primary statistics in void studies: (i) the void size function, which characterises the abundance of voids, and (ii) the void-galaxy cross-correlation function, which contains information about the density and velocity fields in these regions. However, it is necessary a complete description of the effects of geometrical (Alcock-Paczynski effect, AP) and dynamical (Kaiser effect, RSD) distortions around voids in order to design reliable cosmological tests based on these statistics. Observational measurements show prominent anisotropic patterns that lead to biased cosmological constraints if they are not properly modelled. This thesis addresses this problematic by presenting a theoretical and statistical framework based on dynamical and cosmological foundations capable of describing all the underlying effects involved: the expansion effect (t-RSD), the off-centring effect (v-RSD), the AP-volume effect and the ellipticity effect (e-RSD). These effects can be understood by studying the mapping of voids between real and redshift space. In this way, we lay the foundations for a proper modelling of the aforementioned statistics. In addition, we present a new cosmological test based on two perpendicular projections of the correlation function. The method is fiducial-cosmology free, which allows us to effectively break any possible degeneracy between the cosmological parameters involved. Moreover, it allows us to significantly reduce the number of mock catalogues needed to estimate covariances., Comment: PhD thesis in Astronomy (Universidad Nacional de C\'ordoba, Argentina, March 2021). Supervised by Dr. Dante J. Paz. The official version written in Spanish is available at: https://rdu.unc.edu.ar/handle/11086/21041. ICTP-SAIFR Prize in Classical Gravity and Applications (2021). Carlos M. Varsavsky Prize (2022). Related papers: arXiv:1811.12251, arXiv:2007.12064, arXiv:2107.01314, arXiv:2205.13604

We present what we know on nucleosynthesis in the Universe and hypotheses that have been made in this regard. A brief description of the Universe's evolution during its different stages is offered, indicating which are the periods and mechanisms of element formation. A critical prospective on future research is formulated to validate, modify, or reject the hypotheses formulated. These will involve joint observations that encompass finer measurements of cosmic background radiation, galaxy clusters, and gravitational waves produced by neutron star collisions. The information thus obtained will be combined with restrictions given by theoretical models. Perhaps many current doubts will be clarified, but new questions will arise., Comment: 26 pages, 10 figures. Title and abstract also in Spanish

Rather than offering chronologically ordered encyclopedic knowledge of a lifetime, only some of the most striking events of the existence of this well-known scientist are here pointed out. Sections: Life; Man of laws; Interest in philosophy; Astronomer, astrophysicist, cosmologist; The discovery of the expansion of the Universe; Reasonable doubt about the expansion; The astropolitician. Apart from his scientific ideas of cosmological scope, his worldview has been that of a pragmatic thinker with training in law, who converts science into a large company and the scientific hypothesis into a convenient truth that deserves to be defended and arrogated, although deep down it is known that such reasons are not exclusive or original and that there are also reasons to defend the opposite thing. ------ M\'as que ofrecer un conocimiento enciclop\'edico cronol\'ogicamente ordenado de toda una vida, se\~nalar\'e solamente algunos de los eventos m\'as llamativos de la existencia del ampliamente reconocido cient\'ifico. Secciones: Vida; Hombre de leyes; Inter\'es por la filosof\'ia; Astr\'onomo, astrof\'isico, cosm\'ologo; El descubrimiento de la expansi\'on del Universo; Duda razonable sobre la expansi\'on; El astropol\'itico. Aparte de sus ideas cient\'ificas de alcance cosmol\'ogico, su cosmovisi\'on ha sido la de un pensador pragm\'atico con formaci\'on de abogado, que convierte la ciencia en una gran empresa y la hip\'otesis cient\'ifica en una verdad conveniente que merece defenderse y arrogarse, aunque en el fondo se sepa que no son exclusivas ni originales tales razones y que hay tambi\'en razones para defender lo contrario., Comment: 8 pages, in Spanish, to be published as a chapter in "La cosmovisi\'on de los grandes cient\'ificos del siglo XX. Convicciones \'eticas, pol\'iticas, filos\'oficas o religiosas de los protagonistas de las revoluciones cient\'ificas contempor\'aneas", Juan Arana (Ed.), Ed. Tecnos, Madrid

Spanish: La Cosmolog\'ia esta progresando a pasos agigantados gracias a la cantidad espectacular de datos observacionales que se obtienen tanto de los experimentos en tierra como sat\'elites. Un papel fundamental es desempe\~ndo por las observaciones del Fondo C\'osmico de Microondas (CMB por sus siglas en ingl\'e, Cosmic Microwave Background), la cual nos proporciona la prueba observacional m\'as directa de los inicios del Universo. Las observaciones de la temperatura y las anisotrop\'ias en el CMB han jugado un papel fundamental en la definici\'on del modelo cosmol\'ogico. Esta contribuci\'on tiene como objetivo resumir algunos de los conceptos b\'asicos que hay detr\'as de la f\'isica del CMB. La mayor parte de los ingredientes del modelo cosmol\'ogico est\'andar son poco conocidos en t\'erminos de la f\'isica fundamental, por efemplo, la materia oscura y la energ\'ia oscura. Se discute c\'omo las observaciones actuales abordan algunas de estas cuestiones. English: The cosmic microwave background (CMB) provides the most direct observational test of the early universe. The observations of the temperature anisotropies in the CMB have played a key role in defining the cosmological model. This contribution aims to summarize some of the basic concepts behind the physics of the CMB. Most of the ingredients of the standard cosmological model are poorly understood in terms of fundamental physics, for instance, dark matter and dark energy. We discuss how current observations addressed some of these issues., Comment: 6 pages, in Spanish, to appear in the proceedings of the First Astrostatistics School: Bayesian Methods in Cosmology, June 9-13, 2014, Bogot\'a, Colombia

We will make a comparison between the dynamics of spherical gravitational collapse for a perturbed FLRW universe to first order in the context of general relativity, with the corresponding results obtained for the gravitational collapse under theories of modified gravity f(R). This work is aimed at obtaining an analytical model of explanation a source of large scale structures in the universe presenting an approximation of model spherical gravitational collapse under theories of modified gravity f(R)., Comment: 9 pages, in Spanish, to appear in the proceedings of the First Astrostatistics School: Bayesian Methods in Cosmology, June 9-13, 2014, Bogot\'a, Colombia