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Recall that a particle in equilibrium is one for which the external forces are balanced. Static equilibrium involves objects at rest, and dynamic equilibrium involves objects in motion without acceleration; but it is important to remember that these conditions are relative. For instance, an object may be at rest when viewed from one frame of reference, but that same object would appear to be in motion when viewed by someone moving at a constant velocity.
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Combining Microfluidics and Microrheology to Determine Rheological Properties of Soft Matter during Repeated Phase Transitions
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Published on: April 19, 2018

Onsager's variational principle in soft matter.

Masao Doi1

  • 1Department of Applied Physics, University of Tokyo, Hongo, Tokyo, Japan. doi@rheo.t.u-tokyo.ac.jp

Journal of Physics. Condensed Matter : an Institute of Physics Journal
|June 29, 2011
PubMed
Summary
This summary is machine-generated.

Onsager's variational principle provides a unified framework for understanding irreversible processes. This principle simplifies deriving equations for complex soft matter phenomena, establishing a foundation for soft matter physics.

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Area of Science:

  • Soft Matter Physics
  • Non-equilibrium Thermodynamics
  • Statistical Mechanics

Background:

  • Onsager's reciprocal relations extend Rayleigh's principle of least energy dissipation to irreversible processes.
  • Nonlinear and non-equilibrium phenomena in soft matter require robust theoretical frameworks.

Purpose of the Study:

  • To demonstrate the utility of Onsager's variational principle for deriving equations in soft matter physics.
  • To establish Onsager's principle as a general basis for soft matter science.

Main Methods:

  • Application of Onsager's variational principle to derive established equations.
  • Focus on nonlinear and non-equilibrium phenomena in soft matter systems.

Main Results:

  • Onsager's principle offers a convenient framework for deriving equations describing soft matter dynamics.
  • The principle is shown to be applicable to diverse phenomena like phase separation and gel dynamics.

Conclusions:

  • Onsager's variational principle serves as a powerful and general foundation for soft matter physics.
  • The principle unifies the description of various complex soft matter behaviors.