Gravitational search algorithm

What is this algorithm? 

The Gravitational Search Algorithm (GSA) is a metaheuristic optimization algorithm inspired by the law of gravity and the behavior of celestial objects. It was proposed by Rashedi, Nezamabadi-pour, and Saryazdi in 2009. 

My Improved  Gravitational search Optimizer

SCGSA: A sine chaotic gravitational search algorithm for continuous optimization problems     [CODE]

CGSA: Enhance chaotic gravitational search algorithm  by balance adjustment mechanism and sine randomness function for continuous optimization problems     [CODE]