Professor, Dr. Leonid NIZHNIK
Department of Functional Analysis
Institute of Mathematics NAS of Ukraine
Address:
Email: nizhnik (#) imath . kiev . ua
Fax: +(38044) 235 20 30
Room 406
Institute of Mathematics, Tereschenkivska 3,
Kiev, 01 024, Ukraine.
MAIN RESEARCH ACTIVITIES
in functional analysis, differential equations, mathematical physics,
numerical and applied mathematics.
In particular:

Inverse Scattering Problems

Soliton Theory

Spectral Theory

Nonlinear Problems

Mathematical Problems in Electroengineering.
L.Nizhnik was awarded the State Prize of Ukraine in Science and Technology
(1987, 1998) and Ostrogradskii Prize NAS of Ukraine (2006).
He is the author of 4 monographs and over 170 research papers.
RECENT PUBLICATIONS

P.A. Cojuhari and L.P. Nizhnik (2019): Scattering problem for Dirac system with nonlocal potentials,
Methods Funct. Anal. Topology, Vol. 25 , no. 3, 211218.

K. Dębowska and L. Nizhnik (2019): Direct and inverse spectral problems for Dirac systems
with nonlocal potentials, Opuscula Mathematics, 39, no. 5, 645673.

Nizhnik, L. (2018): On the inverse eigenvalue problems for a Jacobi matrix with mixed
given data, Methods of Funct. Anal. Topology, Vol. 24, no. 2, 178–186.

Kuzhel, S. and Nizhnik, L. (2018): Phillips symmetric operators and their extensions,
Banach J. Math. Anal., 12, no. 4, 995–1016.

Cojuhari, P. and Nizhnik, L. (2017): Hochstadt inverse eigenvalue problem
for Jacobi matrices, J. Math. Anal. Appl., 455, 439–451.

Nizhnik, L. and Rabanovich, S. (2017): On new inverse spectral problems for weighted
graphs, Methods of Funct. Anal. Topology, Vol. 23, no. 1, 66–75.

Nizhnik, L. (2015): Inverse spectral problems for Jacobi matrix with finite
perturbed parameters, Methods Funct. Anal. Topology, Vol 21, 3, 256265.

Lebid’,V. and Nizhnik, L. (2015): Spectral analysis of some graphs with
infinite chains, Ukr. Math. J., 66, no.9, 13331345.

Lebid’,V. and Nizhnik, L. (2014): Spectral analysis of locally finite graphs with
one infinite chain, Reports of the National Academy of Sci of Ukraine, no.3,
29–35.

Brasche, J. and Nizhnik, L. (2013): Onedimensional Schrödinger operators with general
point interactions, Methods Funct. Anal.Topology, Vol 19, 1, 415.

Albeverio, S. and Nizhnik, L. (2013): Schrödinger operators with nonlocal potentials,
Methods Funct. Anal.Topology, Vol 19, 3, 199210.

Brasche, J. and Nizhnik, L. (2013): Onedimensional Schrödinger operators
with δ'interactions on a set of Lebesgue measure zero,
Operators and Matrices, Vol.7, 4, 887904.

Nizhnik, L. (2012): Inverse eigenvalue problems for nonlocal SturmLiouville operators
on a star graph, Methods Funct. Anal.Topology, Vol 18, 1, 68  78.

Berezansky, Yu. M., Brasche, J. and Nizhnik, L. P. (2011): On generalized
selfadjoint operators on scales of Hilbert spaces, Methods Funct. Anal. Topology,
Vol 17, 3, 193198.

Nizhnik, L. (2011): Inverse spectral nonlocal problem for the first
order ordinary differential equation, Tamkang J. Mathematics, 42 , 3, 385394.

Dudkin, M. E., Nizhnik, L. P. (2010): Singularly perturbed normal operators,
Methods Funct. Anal. Topology, Vol 16, 4, 298303.

Nizhnik, L. (2009): Inverse eigenvalue problems for nonlocal SturmLiouville operators, Methods Funct. Anal.
Topology, Vol 15, 1, 4147.

Albeverio, S., Kuzhel, S. and Nizhnik, L. (2008):
On the Perturbation Theory of SelfAdjoint Operators, Tokyo Journal of Mathematics, Vol 31, 2, 273292.

Albeverio, S. and Nizhnik, L. (2007):
Schrödinger operators with nonlocal point interactions,
J.Math. Anal. Appl., Vol 332, 2, 884895.

Albeverio, S., Kuzhel, S. and Nizhnik, L. (2007):
Singularly Perturbed SelfAdjoint Operators in Scales of Hilbert spaces,
Ukrain. Math. J., Vol 59, 6, 723743.

Albeverio, S., Hryniv, R. and Nizhnik, L. (2007): Inverse spectral problems
for nonlocal SturmLiouville operators, Inverse Problems,
23, 523535.

Albeverio, S. and Nizhnik, L. (2006):
A Schrödinger operator with δ'interaction on a Cantor set and
KreinFeller operators,
Mathematische Nachrichten, 279, No. 56, 467476.

Nizhnik, L. (2006): A onedimensional Schrödinger operators with point interactions
on Sobolev spaces, J. Funct. Anal. Appl., 40, n. 2, 143147.

Kuzhel, S. and Nizhnik, L. (2006):
Finite Rank SelfAdjoint Perturbations,
Methods Funct. Anal. Topology, 12, n. 3, 243253.
Last updated 28.10.2019
© Irene Nizhnik, 2005.