overview Valentin Keyantuo has been at the Department of Mathematics since 1994. Was the Department Chair from 2007 to 2013. Since 2018, Assistant Dean for Graduate Studies and Research, Faculty of Natural Sciences.
selected publications abstract A characterization of uniform well posedness for degenerate second-order abstract differential equations. Results Math., 78 (2023), paper No. 167. 2023 Fractional integration of imaginary order in Hölder spaces. Archiv Math.,(Basel) 120 (2023), 493–506. 2023 Approximate controllability of Hilfer type fractional differential equations. Vietnam J. Math., 49 (2021), 739-765. 2021 $L^p-$Maximal regularity for degenerate second order integro-differential equations on the real line. J. Fourier Anal. Appl., 26 (2020), paper No. 34, 39p. 2020 Besov Maximal regularity for degenerate second order integro-differential equations on the real line. Math. Methods Appl. Sci.}, 43 (2020), 7239-7268. 2020 Semigroup extensions of locally compact Abelian groups. Topology Appl. 263(2019), 199–208. 2019 Well-posedness for a class of semilinear super-diffusive equations. Nonlinear Analysis, 181(2019), 24-61. 2019 Algebra homomorphisms defined via convoluted semigroups and cosine functions. J. Funct. Anal. 257 (2009), no. 11, 3454--3487. 2009 The wave equation with Wentzell-Robin boundary conditions on $L^p-$spaces. J. Differential Equations, 229 (2006), 634-660. 2006 Fourier multipliers and integro-differential equations in Banach spaces. J. London Math. Soc., (2) 69 (2004), 737-750. 2004
research overview Functional Analysis: Semigroups of Operators and Evolutions. Partial Differential Equations. Control Theory.