Citation: | Antonio Algaba, Cristóbal García, Manuel Reyes, Jaume Giné. ANALYTICAL INTEGRABILITY OF PERTURBATIONS OF DEGENERATE QUADRATIC SYSTEMS[J]. Journal of Applied Analysis & Computation, 2024, 14(2): 864-885. doi: 10.11948/20230188 |
We consider analytic perturbations of quadratic homogeneous differential systems having an isolated singularity at the origin. Here we characterize the analytically integrable perturbations of quadratic homogeneous systems of the form $ (\dot{x}, \dot{y})^T=f_1(P_1, Q_1)^T $ with $ f_1(x, y) $ a non-zero linear homogeneous polynomial and $ P_1(x, y), Q_1(x, y) $ non-zero linear homogeneous polynomials without common factors. We prove that all systems are orbitally equivalent to their quasi-homogeneous leading terms with respect to a certain type but not necessarily to the homogeneous leading terms. This result completes the previous results for the analytic perturbations of irreducible quadratic systems with analytic first integral which are orbitally equivalent to the homogeneous leading term, i.e. all are homogenizable.
[1] | A. Algaba, I. Checa, C. García and J. Giné, Analytic integrability inside a family of degenerate centers, Nonlinear Anal. Real World Appl., 2016, 31, 288–307. doi: 10.1016/j.nonrwa.2016.02.003 |
[2] | A. Algaba, M. Díaz, C. García and J. Giné, Analytic integrability around a nilpotent singularity: The non-generic case. Commun. Pure Appl. Anal., 2020, 19(1), 407–423. doi: 10.3934/cpaa.2020021 |
[3] | A. Algaba, E. Gamero and C. García, The integrability problem for a class of planar systems, Nonlinearity, 2009, 22, 395–420. doi: 10.1088/0951-7715/22/2/009 |
[4] | A. Algaba, C. García and J. Giné, Analytic integrability for some degenerate planar vector fields, J. Differential Equations, 2014, 257(2), 549–565. doi: 10.1016/j.jde.2014.04.010 |
[5] | A. Algaba, C. García and J. Giné, Analytic integrability around a nilpotent singularity, J. Differential Equations, 2019, 267, 443–467. doi: 10.1016/j.jde.2019.01.015 |
[6] | A. Algaba, C. García and M. Reyes, Analytical integrability of degenerate generalized Lotka-Volterra systems, Submitted to publication. |
[7] | A. Algaba, C. García and M. Reyes, Analytical integrability of perturbations of quadratic systems, Mediterr. J. Math., 2021, 18(8), 17 pp. |
[8] | A. Algaba, C. García and M. Reyes, Analytically integrable centers of perturbations of cubic homogeneous, Qual. Theory Dyn. Syst., 2021, 20(2), Paper No. 43, 17 pp. |
[9] | A. Algaba, C. García and M. Reyes, Analytical integrability problem for perturbations of cubic Kolmogorov systems, Chaos Solitons Fractals, 2018, 113, 1–10. doi: 10.1016/j.chaos.2018.05.011 |
[10] | A. Algaba, C. García, M. Reyes and J. Giné, Analytic integrable system orbitally equivalent to a semi-quasihomogeneous system, Nonlinear Anal., 2023, 234, Paper No. 113304, 11 pp. |
[11] | V. V. Basov, Generalized normal form and formal equivalence of two-dimensional systems with zero quadratic approximation III, Differ. Uravn., 2006, 42(3), 308–319. |
[12] | V. V. Basov and A. V. Skitovich, Generalized normal form and formal equivalence of two-dimensional systems with zero quadratic approximation I, Differ. Uravn., 2003, 39(8), 1016–1029. |
[13] | V. V. Basov and A. V. Skitovich, Generalized normal form and formal equivalence of two-dimensional systems with zero quadratic approximation II, Differ. Uravn., 2005, 41(8), 1011–1023. |
[14] | V. V. Basov and E. V. Fedorova, Generalized normal form and formal equivalence of two-dimensional systems with zero quadratic approximation IV, Differ. Uravn., 2009, 45(3), 308–319. |
[15] | A. D Bruno, Local Methods in Nonlinear Differential Equations, Ed. Springer-Verlag, 1980. |
[16] | X. Chen, J. Giné, V. G. Romanovski and D. S. Shafer, The $ 1:-q $ resonant center problem for certain cubic Lotka-Volterra systems, Appl. Math. Comput., 2012, 218(23), 11620–11633. |
[17] | C. Christopher and C. Rousseau, Normalizable, integrable and linearizable saddle points in the Lotka-Volterra system, Qual. Theory Dyn. Syst., 2004, 5(1), 11–61. doi: 10.1007/BF02968129 |
[18] | W. Cong, J. Llibre and X. Zhang, Generalized rational first integrals of analytic differential systems, J. Differ. Equations, 2011, 251(10), 2770–2788. doi: 10.1016/j.jde.2011.05.016 |
[19] |
D. Dolićanin, J. Giné, R. Oliveira and V. G. Romanovski, The center problem for a $ 2:-3 $ resonant cubic Lotka-Volterra system, Appl. Math. Comput., 2013, 220, 12–19.
$ 2:-3 $ resonant cubic Lotka-Volterra system" target="_blank">Google Scholar |
[20] | B. Ferčec and J. Giné, A blow-up method to prove formal integrability for some planar differential systems, J. Appl. Anal. Comput., 2018, 8(6), 1833–1850. |
[21] | B. Ferčec and J. Giné, Blow-up method to compute necessary conditions of integrability for planar differential systems, Appl. Math. Comput., 2019, 358, 16–24. |
[22] | J. Giné and J. Llibre, On the planar integrable differential systems, Z. Angew. Math. Phys., 2011, 62(4), 567–574. doi: 10.1007/s00033-011-0116-5 |
[23] | J. Giné and V. G. Romanovski, Integrability conditions for Lotka-Volterra planar complex quintic systems, Nonlinear Anal. Real World Appl., 2010, 11(3), 2100–2105. doi: 10.1016/j.nonrwa.2009.06.002 |
[24] | M. Han and K. Jiang, Normal forms of integrable systems at a resonant saddle, Ann. Differential Equations, 1998, 14(2), 150–155. |
[25] | C. Liu, G. Chen and G. Chen, Integrability of Lotka-Volterra type systems of degree 4, J. Math. Anal. Appl., 2012, 388(2), 1107–1116. doi: 10.1016/j.jmaa.2011.10.056 |
[26] | C. Liu, G. Chen and C. Li, Integrability and linearizability of the Lotka-Volterra systems, J. Differential Equations, 2004, 198(2), 301–320. doi: 10.1016/S0022-0396(03)00196-7 |
[27] | J. Llibre, C. Valls and X. Zhang, The completely integrable differential systems are essentially linear differential systems, J. Nonlinear Sci., 2015, 25(4), 815–826. doi: 10.1007/s00332-015-9243-z |
[28] | J. F. Mattei and R. Moussu, Holonomie et intégrales premières, Ann. Sci. École Norm. Sup., 1980, 13(4), 469–523. doi: 10.24033/asens.1393 |
[29] | H. Poincaré, Mémoire sur les courbes définies par les équations différentielles, J. Math. Pures Appl., 1885, 4, 167–244; Oeuvres de Henri Poincaré, vol. I. Paris: Gauthier-Villars, 1951, 95–114. |
[30] | E. Stróżyna, Normal forms for germs of vector fields with quadratic leading part. The polynomial first integral case, J. Differential Equations, 2015, 259, 6718–6748. |
[31] |
Q. Wang and W. Huang, Integrability and linearizability for Lotka-Volterra systems with the $ 3:-q $ resonant saddle point, Adv. Difference Equ., 2014, 2014(23).
$ 3:-q $ resonant saddle point" target="_blank">Google Scholar |
[32] | Q. Zhang and Y. Liu, Integrability and generalized center problem of resonant singular point, Appl. Math. Lett., 2015, 40, 13–16. |