Another phenomenon caused by liquid's incompressibility is cavitation. It was proven by the incompressibility method. This is the condition of zero divergence resulting from flow incompressibility. There is also an algebraic version of incompressibility. The first influential paper using the incompressibility method was published in 1980. The incompressibity method depends on an objective, fixed notion of incompressibility. The third equation is the incompressibility condition. Using the incompressibility method, the average case was studied. Liquids inside an internal combustion engine are extremely detrimental because of the incompressibility of liquids. The three properties are&colon; incompressibility (formula 1), density (formula 2) and rigidity (formula 3). Using the incompressibility method, several versions of expanders and superconcentrator graphs were shown to exist.