The DBAR problem, or the
\bar{\partial}
f(z,\bar{z})
g(z)
z=x+iy
R\subseteq\Complex
\bar{\partial}
The DBAR operator is nothing other than the complex conjugate of the operatordenoting the usual differentiation in the complex
z
The DBAR problem is of key importance in the theory of integrable systems, Schrödinger operators and generalizes the Riemann–Hilbert problem.