Phone:
+380 (44) 234 63 22 (office)

Fax:
+380 (44) 235 2010 (office)

E-mail: iyegorch@imath.kiev.ua

Academic Background:
Ph.D. in Math.: 1989, Institute of Mathematics, Kyiv (Supervisor Prof. W.I. Fushchych)
M.Sc. in Math.: 1984, Kyiv National University

Professional Experience: 1985-till now
Research Fellow at the Department of Applied Research of the Institute of Mathematics, Kyiv

Other:
Organization of the First, Second, Third, Fourth, Fifth and Sixth International Conferences ``Symmetry in Nonlinear Mathematical Physics'' (Kyiv, Ukraine, 1995, 1997, 1999, 2001, 2003, 2005)

AREA OF EXPERTISE: Symmetry analysis of differential equations and applications, theory of differential invariants

PUBLICATIONS

1. Yehorchenko I.A. Differential invariants for infinite-dimensional algebras, in Proceedings of the International Conference on SPT 2004, Cala Gonone, Sardinia, Italy 30 May–6 June 2004, Editors G. Gaeta, B. Prinari, S. Rauch-Wojciechowski and S. Terracini, World Scientific, 2005, p. 308-312 [pdf].
2. Yehorchenko I.A. Group classification with respect to hidden symmetry, in Proceedings of Fifth International Conference ``Symmetry in Nonlinear Mathematical Physics'' (23-29 June, 2003, Kyiv), Editors A.G. Nikitin, V.M. Boyko, R.O. Popovych and I.A. Yehorchenko, Kyiv, Institute of Mathematics, 2004, V.50, Part 1, 290-297 [pdf].
3. Yehorchenko I.A., Vorobyova A.I. Sets of conditional symmetry operators and exact solutions for wave and generalised heat equations., in Proceedings of Fifth International Conference ``Symmetry in Nonlinear Mathematical Physics'' (23-29 June, 2003, Kyiv), Editors A.G. Nikitin, V.M. Boyko, R.O. Popovych and I.A. Yehorchenko, Kyiv, Institute of Mathematics, 2004, V.50, Part 1, 298-303 [pdf].
4. Yehorchenko I.A. Differential invariants and construction of conditionally invariant equations, Symmetry in nonlinear mathematical physics, Part 1, Proceedings of Inst. Mathematics of National Akad. Science of Ukraine (Kyiv, 2001), 2002, V. 43, 256-262 [pdf] (see math-ph/0304029).
5. Popovych R.O., Yehorchenko I.A. Group classification of generalized eikonal equations, Ukraïnian Math. Journal, 2001, V. 53, N 11, 1513-1520 (in Ukrainian); translation in Ukrainian Math. J., 2001, V. 53, N 11, 1841-1850 (see math-ph/0112055).
6. Vasilenko O.F., Yehorchenko I.A. Group classification of multidimensional nonlinear wave equations, Group and analytic methods in mathematical physics, Proceedings of Inst. Mathematics of National Akad. Science of Ukraine, Kyiv, 2001, V. 36, 63-66 (in Ukrainian). (pdf)
7. Yehorchenko I.A. On symmetry of a class of first order PDEs equations, Symmetry in nonlinear mathematical physics, Part 1, 2, Proceedings of Inst. Mathematics of National Akad. Science of Ukraine (Kyiv, 1999), 2000, V. 30, 245-248 (pdf).
8. Yehorchenko I.A. Ansatzes and exact solutions for nonlinear Schrödinger and wave equations, Symmetry and analytic methods in mathematical physics (in Ukrainian), Inst. Mathematics of National Akad. Science of Ukraine, Kyiv, 1998, V. 19, 80-87. (pdf)
9. Yehorchenko I.A. Differential invariants for a nonlinear representation of the Poincaré algebra. Invariant equations, Symmetry in nonlinear mathematical physics, Vol. 1, 2, National Akad. Science of Ukraine (Kyiv), 1997, 200-205 (pdf).
10. Yehorchenko I.A. Second-order differential invariants for some extensions of the Poincaré group and invariant equations, J. Nonlin. Math. Phys., 1996, V. 3, no. 1-2, 186-195 (pdf).
11. Fushchych W.I. and Yehorchenko I.A. New conditionally invariant solutions for non-linear d'Alembert equation, Preprint LiTH–MAT–R–93–07, Linköping University, Sweden, 1993, 9 p. (pdf)
12. Yehorchenko I.A. Second-order differential invariants for the Poincaré, Galilei and conformal algebras in many-dimensional spaces, Classical and quantum systems (Goslar, 1991), World Sci. Publishing, River Edge, NJ, 1993, 738-741.
13. Yehorchenko I.A. Nonlinear representation of the Poincaré algebra and invariant equations, Symmetry analysis of equations of mathematical physics, Acad. Sci. Ukraine, Inst. Math., Kyiv, 1992, 62-65.
14. Fushchych W.I. and Yehorchenko I.A. Second-order differential invariants of the rotation group O(n) and of its extensions: E(n); P(1,n); G(1,n), Acta Appl. Math., 1992, V. 28, N 1, 69-92  (pdf).
15. Yehorchenko I.A., Vorobyova A.I. Conditional invariance and exact solutions of the Klein-Gordon-Fock equation, Reports of Akad. Science of Ukraine, 1992, N 1, 19-22, 176 (in Ukrainian).
16. Yehorchenko I.A., Vorobyova A.I. Conditional invariance and exact solutions of a nonlinear heat equation, Reports of Akad. Science of Ukraine, 1992, N 3, 20-22, 160 (in Ukrainian).
17. Fushchych W.I. and Yehorchenko I.A. Non-Lie ansätze and conditional symmetry of the nonlinear Schrödinger equation, Ukraïnian Math. Journal, 1991, V. 43, N 12, 1620-1628 (in Ukrainian); translation in Ukrainian Math. J., 1991, V. 43, N. 12, 1507-1515 (pdf).
18. Fushchych W.I., Zhdanov R.Z. and Yehorchenko I.A. On the reduction of the nonlinear multi-dimensional wave equations and compatibility of the d'Alembert-Hamilton system, J. Math. Anal. Appl., 1991, V. 161, N 2, 352-360 (pdf).
19. Fushchych W.I., Yehorchenko I.A. Reduction and solutions of a nonlinear equation for the vector potential, Reports of Akad. Science of Ukrain SSR, Ser. A, 1991, N 4, 23-25, 158 (in Ukrainian)  (pdf).
20. Fushchich V.I., Yehorchenko I.A. Reduction of a multidimensional nonlinear wave equation to two-dimensional equations, Reports of Akad. Science of Ukrain SSR, Ser. A, 1990, N 8, 32-34, 86 (in Ukrainian) (pdf).
21. Yehorchenko I.A. Differential invariants of Euclidean algebra, Ukrainian Math. Journal, 1990, V. 42, N 6, 767-772 (in Ukrainian); translation in Ukrainian Math. J., 1990, V. 42, no. 6, 676-681.
22. Yehorchenko I.A. Stationary solutions of the nonlinear wave equation, Algebra-theoretic analysis of equations in mathematical physics, Akad. of Science of Ukraine SSR, Institute of Mathematics, Kyiv, 1990, 26-30 (in Russian).
23. Yehorchenko I.A. Exact solutions of the nonlinear Schrödinger equation, Symmetry and solutions of equations of mathematical physics, Akad. of Science of Ukrain. SSR, Inst. Mathematics, Kyiv, 1989, 17-20 (in Russian).
24. Yehorchenko I.A. Symmetry properties of nonlinear equations for a complex vector field, Akad. Science of Ukrain. SSR, Kyiv, Inst. Mat. Preprint N 89.48, 1989, 39 p. (in Russian).
25. Fushchych W.I. and Yehorchenko I.A. Differential invariants of the Poincaré algebra and of the conformal algebra, Reports of Akad. Science of Ukrain SSR, Ser. A, 1989, N 5, 21-22 (in Ukrainian) (pdf).
26. Fushchych W.I. and Yehorchenko I.A. Differential invariants of the Galilei algebra, Reports of Akad. Science of Ukrain SSR, Ser. A, 1989, N 4, 29-32, 86 (in Russian) (pdf).
27. Fushchych W.I. and Yehorchenko I.A. The symmetry and exact solutions of the nonlinear d'Alembert equation for complex fields, J. Phys. A, 1989, V. 22, N 14, 2643-2652 (pdf).
28. Yehorchenko I.A., Vorobyova A.I. Exact solutions of the wave equation with additional conditions, Symmetry and solutions of equations of mathematical physics, Akad. of Science of Ukrain. SSR, Inst. Mathematics, Kyiv, 1989, 21-25 (in Russian).
29. Yehorchenko I.A. Complex generalization of the Hamilton-Jacobi equation and its solutions, Symmetry analysis and solutions of equations of mathematical physics, Akad. of Science of Ukrain. SSR, Inst. Mathematics, Kyiv, 1988, 4-8 (in Russian).
30. Fushchych W.I., Yehorchenko I.A. Symmetric properties of complex-valued nonlinear wave equations, Reports of Akad. Science of SSSR, 1988, V. 298, N 2, 347-351 (in Russian) (pdf); translation in Soviet Phys. Report, 33 (1988), N 1, 36-38.
31. Yehorchenko I.A. Particular solutions of two systems of nonlinear multidimensional wave equations, Symmetry and solutions of nonlinear equations of mathematical physics, Akad. of Science of Ukrain. SSR, Inst. Mathematics, Kyiv, 1987, 47-54 (in Russian).
32. Yehorchenko I.A. Poincaré-invariant quasilinear wave equations for complex-valued functions, Akad. Science of Ukrain. SSR, Kyiv, Inst. Mat., Preprint N 87.3, 1987, 27 p. (in Russian).
33. Yehorchenko I.A. On the group classification of equations for a complex vector potential, Group-theoretic investigations of the equations of mathematical physics, Akad. of Science of Ukrain. SSR, Inst. Mathematics, Kyiv, 1985, 66-70 (in Russian).