Areas of interest:
Geometric
Function
Theory, Spaces of Analytic Functions and Operators Acting on Them,
Approximation Theory.
Specific problems and topics
I have
been studying and/or am studying now:
- Hyperbolic, Schwarzian, and angular derivative of holomorphic
self-maps of the disk
- Commuting analytic self-maps of the disk and iteration of self-maps of the disk
- (Weighted) composition
operators on spaces of analytic functions: norms, isometries, adjoints, spectral theory
- Norms and essential norms of composition
operators acting on Bergman
spaces
- Integrability of derivatives of conformal maps and growth of intergral means
- Integrability of derivatives of Blaschke
products; relationship
with interpolating sequences
- Uniformly discrete sequences in the disk, Nyquist/Seip
densities, interpolation
and sampling
- Dirichlet-type spaces (especially analytic Besov spaces,
etc.)
in the
disk
- Planar domains related to the images of the
disk by
conformal
maps; univalent interpolation
- Superposition operators on spaces of Dirichlet
type and other spaces
- Applications of inequalities of the
Trudinger-Moser
type
in Complex Analysis
- General theory of Hardy and Bergman spaces
- Toeplitz operators on Bergman and Hardy spaces:
range and
kernel, and zero products
- Analytic Toeplitz operators (pointwise
multiplication operators)
- The Berezin transform and its applications
- Nonlinear problems (maximizing Rayleigh-type
quotients) and
weighted Bergman spaces
- Extremal problems for linear functionals in
spaces of analytic functions
- Extremal problems for non-vanishing functions in spaces of analytic functions (including the Krzyz conjecture)
- Taylor coefficients of functions in Bergman
spaces
and coefficient
multipliers
- Hilbert matrix as an operator on function spaces
- Hardy spaces of Dirichlet series