Adiabat
= Adiabat
An <adiabat> is a curve representing a quasistatic adiabatic change. In a reversible description it is also a curve of constant <entropy>. For an <ideal gas> with constant heat-capacity ratio $\gamma$, it obeys $pV^\gamma=\mathrm{constant}$. A general irreversible <adiabatic process> need not follow this equilibrium-state curve and can produce <entropy>.