• functional analysis (semigroup theory, operator theory)
• ergodic theory (functional analytic view, mixing properties)
  
• complex analysis (location of zeros of entire functions)
  

pdf-file

• Stability of Operators and Operator Semigroups, book manuscript, accepted by Operator Theory: Advances and Applications, Birkhäuser Verlag (180 pages).
• Rigidity of contractions on Hilbert spaces, submitted.
  
• A "typical" contraction is unitary, submitted.
• (with András Serény) On the weak analogue of the Trotter-Kato theorem, Taiwanese J. Math., to appear. [pdf-file]
• Embedding operators into strongly continuous semigroups, Arch. Math. (Basel) 92 (2009), 451-460. [pdf-file]
  
• (with András Serény) Category theorems for stable semigroups, Ergodic Theory Dynamical Systems 29 (2009), 487-494. [pdf-file]
• (with Hans Zwart) The growth of a C₀-semigroup characterised by its cogenerator, J. Evol. Equ. 8 (2008), 749-764. [pdf-file]
• (with András Serény) Category theorems for stable operators on Hilbert spaces, Acta Sci. Math. (Szeged) 74 (2008), 259-270. [pdf-file]
• (with András Bátkai and Yuri Latushkin) The spectral mapping property of delay semigroups, Compl. Anal. Oper. Theory 2 (2008), 273-283. [pdf-file]
• (with Bálint Farkas) Weak stability of orbits of C₀-semigroups on Banach spaces. In H. Amann, W. Arendt, M. Hieber, F. Neubrander, S. Nicaise, J. von Below (eds), Functional Analysis and Evolution Equations. The Günter Lumer Volume (2007), 201-208.
• (with Hans Zwart) A note on polynomially growing C₀-semigroups, Semigroup Forum 75 (2007), 438-445. [pdf-file]
• (with Bálint Farkas, Rainer Nagel and András Serény) Weakly and almost weakly stable C₀-semigroups, Int. J. Dyn. Syst. Differ. Equ. 1 (2007), 44-57. [pdf-file]
• (with Hans Zwart) Continuous-time Kreiss resolvent condition on infinite-dimensional spaces, Math. Comp. 75 (2006), 1971-1985. [pdf-file]
  
• Polynomially bounded semigroups, Semigroup Forum 70 (2005), 118-126. [pdf-file]
• (with Olga M. Katkova and Anna M. Vishnyakova) On entire functions having Taylor sections with only real zeros, Mat. Fiz. Anal. Geom. 11 (2004), 449-469.
• (with Olga M. Katkova and Anna M. Vishnyakova) On power series having sections with only real zeros, Comput. Methods Funct. Theory 3 (2003), 425-441.
• On variation preserving operators, Mat. Fiz. Anal. Geom. 10 (2003), 94-105.
  

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