Question

According to Kirchhoff's theorem, the cofactors of a matrix representation of this operator count the number of spanning trees. In algebraic graph theory, the discrete form of this operator is the difference between the degree (15[1])and adjacency matrices. (15[1])Elliptic operators generalize this operator, whose kernel consists of functions that satisfy the maximum principle, meaning they attain extrema on their boundary. A function f is harmonic if this operator of f equals zero; that (*) PDE is named after this operator’s namesake and is the homogeneous version of Poisson’s equation. The divergence of the gradient gives this operator, which is symbolized with a triangle or as del-squared. For 10 points, give this differential operator named for a French mathematician who also has a namesake real-to-complex transform. ■END■

ANSWER: Laplacian [or Laplace operator; accept del-squared until read; accept Laplacian matrix; accept Laplace’s equation; prompt on harmonic until read by asking “what is the more common name of that operator?”]
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Buzzes

PlayerTeamOpponentBuzz PositionValue
Swapnil GargBerkeley ABerkeley B3415
Michal GerasimiukStanfordBerkeley Past3715