University of Bío-Bío

Slowly rotating condensate dark stars beyond the mean-field approximation

Abstract We investigate rotational properties and universal relations of slowly rotating Bose–Einstein condensate dark stars in the context of General Relativity, both at the mean-field level and when the leading beyond-mean-field Lee–Huang–Yang correction is retained self-consis...

Gödel-symmetric backgrounds and explicit spacetime symmetry breaking

Abstract Explicit diffeomorphism breaking in gravitational theories with nondynamical background fields is constrained by the compatibility between the modified Einstein equations and the contracted Bianchi identities. We implement an isometry-based approach in which the backgrou...

Predicting Early Dropout in University Entry Cohorts: Temporal Inter-Cohort Validation in a Chilean Public University

Early university dropout remains a major concern for higher education, particularly amid expanded access, diverse student profiles, and institutional efforts to promote persistence. This study evaluates predictive models of early dropout at a Chilean university using ten entry co...