We study the homogeneous Riemann-Hilbert problem with a vanishing scalar-valued continuous coefficient. We characterize non-existence of nontrivial solutions in the case where the coefficient has its values along several rays starting from the origin. As a consequence, some results on injectivity and existence of eigenvalues of Toeplitz operators in Hardy spaces are obtained.
@article{bwmeta1.element.doi-10_2478_conop-2012-0004, author = {A. Per\"al\"a and J. A. Virtanen and L. Wolf}, title = {A Riemann-Hilbert problem with a vanishing coefficient and applications to Toeplitz operators}, journal = {Concrete Operators}, volume = {1}, year = {2013}, pages = {28-36}, zbl = {1273.35206}, language = {en}, url = {http://dml.mathdoc.fr/item/bwmeta1.element.doi-10_2478_conop-2012-0004} }
A. Perälä; J. A. Virtanen; L. Wolf. A Riemann-Hilbert problem with a vanishing coefficient and applications to Toeplitz operators. Concrete Operators, Tome 1 (2013) pp. 28-36. http://gdmltest.u-ga.fr/item/bwmeta1.element.doi-10_2478_conop-2012-0004/
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