arXiv subjects

Matheus Lazarotto

Publications and source records attributed to Matheus Lazarotto.

3 recordsLinked to original sources

arXiv2026

An angular-momentum preserving dissipative model for the point-mass N -body problem

A simple mathematical model emulating energy dissipation due to tidal effects is proposed. In this model, forces acting between masses remove energy but preserve the total angular momentum of the system. We study the effect of such forces on the particular family of orbits in central configurations, and show that a specific dependence on the mutual distances between the bodies leads to homographic equations equivalent to those of the two-body problem with dissipation. We then describe in detail the topology of solutions of the dissipative two-body system via Poincar\'e compactification. Finally, we present equations averaged over Keplerian motion showing no influence of the dissipation on periapsis precession.

nlin.CD↗

arXiv2024

Benchmark: Tao's symplectic integration method

A benchmark test was conducted for a new symplectic integration method originally developed by Molei Tao. The method raises interest due to its explicit evolution equation, with applicability to both separable and non-separable Hamiltonian systems, and an easy-to-implement, easily generalizable algorithm. In order to compare the method with other, more well-known methods, namely Störmer-Verlet and Runge-Kutta, we conducted a series of benchmark tests comparing their performance in terms of CPU time, system invariants functions conservation, and numerical symplectic area conservation. Overall, it was found that despite being slower than the more optimized Runge-Kutta-Cash-Karp, Tao's method presents a similar performance to Störmer-Verlet, with the extra perk of being more generic and not requiring the use of implicit equations for the evolution of the equations of motion.

physics.comp-ph↗

arXiv2024

Island myriads in periodic potentials

A phenomenon of emergence of stability islands in phase-space is reported for two periodic potentials with tiling symmetries, one square and the other hexagonal, inspired by bidimensional Hamiltonian models of optical lattices. The structures found, here termed as island myriads, resemble web-tori with notable fractality and arise at energy levels reaching that of unstable equilibria. In general, the myriad is an arrangement of concentric island chains with properties relying on the translational and rotational symmetries of the potential functions. In the square system, orbits within the myriad come in isochronous pairs and can have different periodic closure, either returning to their initial position or jumping to identical sites in neighbor cells of the lattice, therefore impacting transport properties. As seen when compared to a more generic case, i.e. the rectangular lattice, the breaking of square symmetry disrupts the myriad even for small deviations from its equilateral configuration. For the hexagonal case, the myriad was found but in attenuated form, mostly due to extra instabilities in the potential surface that prevent the stabilization of orbits forming the chains.

nlin.PS↗