A second-order dynamical approach with variable damping to nonconvex smooth minimization
Radu Ioan Boţ1, Ernö Robert Csetnek1, Szilárd Csaba László2
1Faculty of Mathematics, University of Vienna, Vienna, Austria.
Summary
This study introduces a second-order dynamical system for minimizing nonconvex functions. The system
Area of Science:
- Optimization Theory
- Dynamical Systems
- Non-convex Analysis
Background:
- Minimizing non-convex functions is challenging due to local minima.
- Second-order dynamical systems offer potential for efficient optimization.
- Nesterov's accelerated gradient method provides a benchmark for convex optimization.
Purpose of the Study:
- To investigate a second-order dynamical system with variable damping for non-convex function minimization.
- To analyze the convergence properties of this dynamical system.
- To establish convergence rates based on the Kurdyka-Lojasiewicz property.
Main Methods:
- Formulating a second-order dynamical system inspired by Nesterov's accelerated gradient method.
- Applying regularization to the objective function.
- Analyzing the system's trajectory convergence under the Kurdyka-Lojasiewicz property.
Main Results:
- The generated trajectory converges to a critical point under specific regularization conditions.
- Convergence rates are provided, dependent on the Lojasiewicz exponent.
- The variable damping mechanism is shown to be effective.
Conclusions:
- The proposed second-order dynamical system is a viable approach for non-convex function minimization.
- The Kurdyka-Lojasiewicz property is crucial for guaranteeing convergence.
- The study offers theoretical insights into the convergence behavior of accelerated methods for non-convex problems.
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