Regularity of a J-holomorphic curve
= Regularity of a J-holomorphic curve
{title2=$D_u\text{ is surjective}$}
A <J-holomorphic curve> is regular when the linearized <Cauchy–Riemann operator> is <surjective>. Regularity only for simple curves is weaker than regularity for all maps: multiple covers of an exceptional sphere can fail regularity even when that simple sphere is regular.