77 citations
5 papers
Ordinary differential equations with singular coefficients: an intrinsic formulation with applications to the Euler-Bernoulli beam equation
Nuno Costa Dias, Cristina Jorge, Joao Nuno Prata
We study a class of linear ordinary differential equations (ODE)s with distributional coefficients. These equations are defined using an {\it intrinsic} multiplicative product of S…
Spherical collapse in coupled quintessence with a CDM background
Bruno J. Barros, Tiago Barreiro, Nelson J. Nunes
In this work we study the growth of cold dark matter density perturbations in the nonlinear regime on a conformally coupled quintessence model in which the background is designed t…
Ordinary differential equations with point interactions: An inverse problem
Nuno Costa Dias, Cristina Jorge, Joao Nuno Prata
Given a linear ordinary differential equation (ODE) on $\RE$ and a set of interface conditions at a finite set of points $I \subset \RE$, we consider the problem of determining ano…
Hamiltonian analysis of the BFCG formulation of General Relativity
Aleksandar Mikovic, Miguel A. Oliveira, Marko Vojinovic
We perform the complete Hamiltonian analysis of the BFCG action for General Relativity. We determine all the constraints of the theory and classify them into the first-class and th…
Coupled quintessence with a CDM background: removing the tension
Bruno J. Barros, Luca Amendola, Tiago Barreiro +1
A well-known problem of the CDM model is the tension between the relatively high level of clustering, as quantified by the parameter , found in cosmic microwave background…