The well-known hypervirial perturbation method (HPM), based on hypervirial relations and the Hellmann-Feynman theorem, is suitable for the calculation of perturbation corrections of large order for the non-relativistic, ...

We study non-linear structure formation in the presence of dark energy. The influence of dark energy on the growth of large-scale cosmological structures is exerted both through its background effect on the expansion rate, ...

We study non-linear structure formation in the presence of dark energy. The influence of dark energy on the growth of large-scale cosmological structures is exerted both through its background effect on the expansion rate, ...

We apply the Lindstedt–Poincaré method to the Lotka–Volterra model and discuss alternative implementations of the approach. By means of an efficient systematic algorithm we obtain an unprecedented number of perturbation ...

In this paper are considered periodic perturbations, depending on two parameters, of planar polynomial vector fields having an annulus of large amplitude periodic orbits, which accumulate on a symmetric infinite heteroclinic ...

We consider the transverse-momentum (qT) distribution of Higgs bosons produced at hadron colliders. We use a formalism that uniformly treats both the small-qT and large-qT regions in QCD perturbation theory. At small qT ...

We have applied the Lindstedt-Poincaré method to study the limit cycle of the van der Pol oscillator, obtaining the numerical coefficients of the series for the period and for the amplitude to order 859. Hermite-Padé ...

We show that a system of four particles in a one-dimensional box with a two-particle harmonic interaction can by described by means of the symmetry point group Oh. Group theory proves useful for the discussion of both the ...