Unstable motions in Celestial Mechanics
Accés obert
 
10 d’abr. 2024
16 visualitzacions
 
Guardia, Marcel
Full Professor at the Department of Mathematics at Universitat de Barcelona

One of the oldest problems in dynamical systems is the stability of the Solar System. That is, consider N bodies moving following Newton's law of gravitation, one of them with large mass (the Sun) and the others with small masses (the planets). If one neglects, the gravitational interaction between planets, the classical Kepler's laws assert that the planets move on ellipses. Then, one wants to understand whether the effect of the planets mutual attraction causes long term changes on the shape and relative position of the Keplerian ellipses.
Nowadays, it is known that the answer to the stability of the Solar system is rather nuanced and that stability and instability coexist for nearby initial conditions. In this talk I will explain how to construct unstable motions in this model, which lead to drastic changes in the semimajor axes, eccentricity and inclination of these ellipses.

 
Llicència: Reconocimiento-NoComercial-SinObraDerivada 3.0 España (CC BY-NC-ND 3.0 ES)
 

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