Place of Publication
BOLETIN DE LA SOCIEDAD MATEMATICA MEXICANA
In the scalar case, the spectral factorization mapping f -> f(+) puts a nonnegative integrable function f having an integrable logarithm in correspondence with an outer analytic function f(+) such that f = vertical bar f(+)vertical bar(2) is almost everywhere. The main question addressed here is to what extent parallel to f(+) - g(+)parallel to(H2) is controlled by parallel to f - g parallel to(L1) and parallel to log f - log g parallel to(L1).
Ephremidze, Lasha; Shargorodsky, Eugene; and Spitkovsky, Ilya, Quantitative results on continuity of the spectral factorization mapping in the scalar case (2016).