Factorization of functions in generalized Nevanlinna classes

Authors
Citation
C. Horowitz, Factorization of functions in generalized Nevanlinna classes, P AM MATH S, 127(3), 1999, pp. 745-751
Citations number
10
Categorie Soggetti
Mathematics
Journal title
PROCEEDINGS OF THE AMERICAN MATHEMATICAL SOCIETY
ISSN journal
00029939 → ACNP
Volume
127
Issue
3
Year of publication
1999
Pages
745 - 751
Database
ISI
SICI code
0002-9939(199903)127:3<745:FOFIGN>2.0.ZU;2-#
Abstract
For functions in the classical Nevanlinna class analytic projection of log \f (e(i theta))\ produces log F(z) where F is the outer part of f; i.e., th is projection factors out the inner part of f. We show that if log \f(z)\ i s area integrable with respect to certain measures on the disc, then the ap propriate analytic projections of log \f\ factor out zeros by dividing f by a natural product which is a disc analogue of the classical Weierstrass pr oduct. This result is actually a corollary of a more general theorem of M. Andersson. Our contribution is to give a simple one complex variable proof which accentuates the connection with the Weierstrass product and other can onical objects of complex analysis.