Four-body co-circular central configurations

We classify the set of central configurations lying on a common circle in the Newtonian four-body problem. Using mutual distances as coordinates, we show that the set of four-body co-circular central configurations with positive masses is a two-dimensional surface, a graph over two of the exterior s...

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Bibliographic Details
Authors: Cors Iglesias, Josep Maria|||0000-0002-9803-8490, Roberts, Gareth E.
Format: article
Publication Date:2012
Country:España
Institution:Universitat Politècnica de Catalunya (UPC)
Repository:UPCommons. Portal del coneixement obert de la UPC
Language:English
OAI Identifier:oai:upcommons.upc.edu:2117/21123
Online Access:https://hdl.handle.net/2117/21123
https://dx.doi.org/10.1088/0951-7715/25/2/343
Access Level:Open access
Keyword:Many-body problem
Celestial mechanics
Convex central configurations
Relative equilibria
Problema dels cossos múltiples
Mecànica celest
Classificació AMS::70 Mechanics of particles and systems::70F Dynamics of a system of particles, including celestial mechanics
Àrees temàtiques de la UPC::Matemàtiques i estadística
Àrees temàtiques de la UPC::Enginyeria mecànica
Description
Summary:We classify the set of central configurations lying on a common circle in the Newtonian four-body problem. Using mutual distances as coordinates, we show that the set of four-body co-circular central configurations with positive masses is a two-dimensional surface, a graph over two of the exterior side-lengths. Two symmetric families, the kite and isosceles trapezoid, are investigated extensively. We also prove that a co-circular central configuration requires a specific ordering of the masses and find explicit bounds on the mutual distances. In contrast to the general four-body case, we show that if any two masses of a four-body co-circular central configuration are equal, then the configuration has a line of symmetry.