General conditions for the existence of non-standard Lagrangians for dissipative dynamical systems
نویسنده
چکیده
Equations of motion describing dissipative dynamical systems with coefficients varying either in time or in space are considered. To identify the equations that admit a Lagrangian description, two classes of non-standard Lagrangians are introduced and general conditions required for the existence of these Lagrangians are determined. The conditions are used to obtain some non-standard Lagrangians and derive equations of motion resulting from these Lagrangians.
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Standard and non-standard Lagrangians for dynamical systems
Dynamical systems described by equations of motion with the first-order time derivative (dissipative) terms of even and odd powers, and coefficients varying either in time or in space, are considered. Methods to obtain standard and nonstandard Lagrangians are presented and used to identify classes of equations of motion that admit a Lagrangian description. It is shown that there are two general...
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