Otherwise, the evolution equations still may hold approximately, provided fluctuations are small.

Systems of evolution equations with periodic and quasiperiodic coefficients.

The notion of evolution equations is intimately tied in with another aspect of general relativistic physics.

As a result, the evolution equations for the wave motion become:

This description is more closely tied to Maxwell's equations as an evolution equation for the electric field exists.

A large number of evolution equations have been formulated in this way, motivated by different specific requirements (see the abovementioned book references for further information).

The evolution equation is also linear in probability, for fundamental reasons.

Symmetry considerations can now be taken into account, and evolution equations obtained for the complex amplitudes governing the solution.

In other words, the above equation gives us the evolution equation for the expansion of the timelike congruence.

A geometric flow is also called a geometric evolution equation.