\chi = 2 - 2g

February 22, 2026

$\chi = 2 - 2g$

Related Articles

Kubo Won’t Let Me Disappear: The Bewildering Truth Behind His Invisibility Struggle
A mathematician working on the application of algebraic topology is analyzing a closed, orientable surface. Suppose the Euler characteristic of the surface is given by the formula \(\chi = 2 - 2g\), where \(g\) is the genus of the surface. If the surface is a double torus (i.e., \(g = 2\)), what is its Euler characteristic?
To find the Euler characteristic of a double torus, we use the given formula:
where \(g\) is the genus of the surface. For a double torus, \(g = 2\). Substituting this value into the formula, we get:
\chi = 2 - 2 \times 2 = 2 - 4 = -2
Therefore, the Euler characteristic of a double torus is \(\boxed{-2}\).

Trending Articles