Source condition for quadratic regularization (source code)

= Source condition for quadratic regularization
{title2=$u^\dagger=K^*v$}

This range condition puts the exact solution in the <operator range> of the <adjoint operator>. It controls the small-<singular value> components of the solution and supplies convergence rates for <spectral regularization methods>. It is the quadratic-penalty case of a <source condition in variational regularization>.