Liouville surface explained

In the mathematical field of differential geometry a Liouville surface (named after Joseph Liouville) is a type of surface which in local coordinates may be written as a graph in R3

z=f(x,y)

such that the first fundamental form is of the form

ds2=(f1(x)+

2+dy
f
2(y))\left(dx

2\right).

Sometimes a metric of this form is called a Liouville metric. Every surface of revolution is a Liouville surface.

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