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### Browsing by Author "Alfaro Solís, Jorge Luis"

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- ItemA finite quantum gravity field theory model(2011) Alfaro Solís, Jorge Luis; González Villarroel, Pablo Emilio; Avila Vivero, Ricardo Andrés
Show more - ItemA Sim(2) invariant dimensional regularization(2017) Alfaro Solís, Jorge Luis
Show more - ItemAlgebra of Higher Antibrackets(1996) Bering K.; Alfaro Solís, Jorge Luis
Show more - ItemAlternative Approaches to Lorentz Violation Invariance in Loop Quantum Gravity Inspired Models(2004) Alfaro Solís, Jorge Luis
Show more - ItemAn Accelerating Universe without Lambda: Delta Gravity Using Monte Carlo(2019) Alfaro Solís, Jorge Luis; San Martín Hormazábal, Marco; Sureda Hernández, Joaquín Miguel
Show more A gravitational field model based on two symmetric tensors, gμν and g˜μν , is studied, using a Markov Chain Monte Carlo (MCMC) analysis with the most updated catalog of SN-Ia. In this model, new matter fields are added to the original matter fields, motivated by an additional symmetry ( δ˜ symmetry). We call them δ˜ matter fields. This theory predicts an accelerating Universe without the need to introduce a cosmological constant Λ by hand in the equations. We obtained a very good fit to the SN-Ia Data, and with this, we found the two free parameters of the theory called C and L2 . With these values, we have fixed all the degrees of freedom in the model. The last H0 local value measurement is in tension with the CMB Data from Planck. Based on an absolute magnitude MV=−19.23 for the SN, Delta Gravity finds H0 to be 74.47±1.63 km/(s Mpc). This value is in concordance with the last measurement of the H0 local value, 73.83±1.48 km/(s Mpc).Show more - ItemAstronomy meets biology: EFOC2 and the chirality of life.(2010) Sterzik, M.; Azúa Bustos, Armando; Alfaro Solís, Jorge Luis; Vicuña, Rafael
Show more - ItemBARE AND INDUCED LORENTZ AND CPT INVARIANCE VIOLATIONS IN QED(2010) Alfaro Solís, Jorge Luis
Show more - ItemBose-Einstein graviton condensate in a Schwarzschild black hole(2018) Alfaro Solís, Jorge Luis; Espriu, Domenec; Gabbanelli, Luciano
Show more - ItemBosonic (p-1)-forms in Einstein-Cartan theory of gravity(2014) Alfaro Solís, Jorge Luis; Riquelme Muñoz, Simón Darío
Show more - ItemBrst Formulation of Partition Function Constraints(1997) Alfaro Solís, Jorge Luis
Show more - ItemChiral Lagrangians and the Qcd String(1999) Alfaro Solís, Jorge Luis
Show more - ItemCondensates beyond the horizons(2020) Alfaro Solís, Jorge Luis; Espriu, D-; Gabbanelli, L.
Show more - ItemCosmic inflation in modified models of gravity and an analysis on gravitational waves(2021) Gamonal San Martín, Mauricio; Alfaro Solís, Jorge Luis; Pontificia Universidad Católica de Chile. Facultad de Física
Show more This work comprises three different lines of research related to the study of cosmological inflation and the propagation of gravitational waves. In the first issue, we developed -for the first time in a systematic way- the slow-roll approximation for a single field inflaton within the framework of f(R,T) gravity, a modified model of gravity such that the Lagrangian is a function of the scalar curvature and the trace of the energy-momentum tensor. We obtained the modified slow-roll parameters and the spectral indices by choosing a minimal coupling between matter and gravity. We computed these quantities for several models and contrasted the predictions with the constraints of the Planck data, obtaining corrections to the Starobinsky model. In the second line of research, we studied how a free Lorentz-valued bosonic 0-form coupled to Einstein-Cartan gravity's action can be considered the inflaton field. In this model, the interacting terms of the fields come directly from the torsionful contributions of the action. Hence, the inflationary dynamics can be extended so that we can define an effective potential that describes the evolution of the background fields. We found that for a particular combination of initial conditions, the model could adequately guarantee the slow-roll conditions over more than 55 e-folds. However, a more detailed analysis is required to confirm the viability of this inflationary scenario. Finally, we addressed a different problem related to the propagation of low-frequency gravitational waves coming from sources located at cosmological distances. Within the linearized regime of gravity, we performed a coordinate system transformation between a frame which origin is the source of gravitational waves and the comoving frame of the FLRW metric. Then, we studied the observational consequences in Pulsar Timing Arrays experiments, finding a non-trivial modification to the timing residual of pulsars that depends on the value of the Hubble constant.Show more - ItemCosmological applications of delta-gravity(2012) Alfaro Solís, Jorge Luis
Show more - ItemCosmological Fluctuations in Delta Gravity(2023) Alfaro Solís, Jorge Luis; Rubio, Carlos; San Martín, Marco
Show more About 70% of the Universe is Dark Energy, but the physics community still does not know what it is. Delta gravity (DG) is an alternative theory of gravitation that could solve this cosmological problem. Previously, we studied the Universe’s accelerated expansion, where DG was able to explain the SNe-Ia data successfully. In this work, we computed the cosmological fluctuations in DG that give rise to the CMB through a hydrodynamic approximation. We calculated the gauge transformations for the metric and the perfect fluid to present the equations of the evolution of cosmological fluctuations. This provided the necessary equations to solve the scalar TT power spectrum in a semi-analytical way. These equations are useful for comparing the DG theory with astronomical observations and thus being able to constrain the DG cosmology.Show more - ItemCosmology in delta-gravity(2013) Alfaro Solís, Jorge Luis; González Villarroel, Pablo Emilio
Show more - ItemDelta gravity and the accelerated expansion of the universe(2011) Alfaro Solís, Jorge Luis
Show more - ItemDelta Gravity, Delta Matter and the Accelerated Expansion of the Universe(2019) Alfaro Solís, Jorge Luis; González, Pablo
Show more - ItemDelta-Gravity(2013) Alfaro Solís, Jorge Luis
Show more - ItemDelta-gravity and dark energy(2012) Alfaro Solís, Jorge Luis
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