Speaker
Description
The influence of the extra dimension on the static equilibrium configurations and the stability against radial perturbations are analyzed. These studies are investigated by using the stellar structure equations and the radial perturbation equations, both modified for a $d$-dimensional spacetime. We obtain that the spacetime dimension influences in both structure and stability of an object, whose fluid contained in it follows a linear equation of state, in this case the MIT bag model equation of state is considered. For an interval of central energy densities $\rho_c\,G_d$ and total masses $MG_d/(d-3)$, when the dimension is increased the stars gain more stability. We also show that the value of $\rho_c\,G_d$ used to obtain the maximum value of $M{G_d}/(d-3)$ is the same used to obtain the zero eigenfrecuency of oscillation, i.e., the peak value of $M{G_d}/(d-3)$ marks the onset of instability. This indicates that the necessary and sufficient conditions to recognize regions constructed by stable and unstable equilibrium configurations against radial perturbations are respectively $dM/d\rho_c>0$ and $dM/d\rho_c<0$.
