Abstract
The Lotka-Volterra system of autonomous differential equations consists in three homogeneous polynomial equations of degree 2 in three variables. This system, or the corresponding vector fieldLV(A, B, C), depends on three nonzero (complex) parameters and may be written asLV(A, B, C)=V x∂x+V y∂y+V z∂zwhereV x=x(Cy+z), Vy=y(Az+x), Vz=z(Bx+y). Similar systems of equations have been studied by Volterra in his mathematical approach of the competition of species and this is the reason why this name has been given to such systems.
In fact,LV(A, B, C) can be chosen as a normal form for most of factored quadratic systems; the study of its first integrals of degree 0 is thus of great mathematical interest.
Given a homogeneous vector field, there is a foliation whose leaves are homogeneous surfaces in the three-dimensional space (or curves in the corresponding projective plane), such that the trajectories of the vector field are completely contained in a leaf. A first integral of degree 0 is then a function on the set of all leaves of the previous foliation.
In the present paper, we give all values of the triple (A, B, C) of non-zero parameters for whichLV(A, B, C) has a homogeneous liouvillian first integral of degree 0. We also discuss the corresponding problem of liouvillian integration for quadratic factored vector fields that cannot be put in Lotka-Volterra normal form.
Our proof essentially relies on combinatorics and elementary algebraic geometry, especially in proving that some conditions are necessary.
Similar content being viewed by others
References
L. Cairo and J. Llibre,Integrability and algebraic solutions for the 2-D Lotka-Volterra system, preprint 1997.
C. Camacho andA. Lins Neto,The topology of integrable differentiable forms near a singularity, Public. Math. IHES55 (1982), 5–36.
D. Cerveau and J. F. Mattei,Formes intégrables holomorphes singulières, Astérisques,97, 1982.
D. Cerveau andF. Maghous,Feuilletages algébriques de C n, C. R. Acad. Sci. Paris,303 (1986), 643–645.
D. Cerveau,Equations différentielles algébriques: remarques et problémes, J. Fac. Sci. Univ. Tokyo, Sect. I-A, Math.,36 (1989), 665–680.
J. Chavarriga, J. Llibre and J. Moulin Ollagnier,About a relation of Darboux in enumerative geometry, preprint, December 2000.
G. Darboux,Mémoire sur les équations différentielles algébriques du premier ordre et du premier degré, Bull. Sc. Math. 2ème sériet. 2 (1878), 60–96, 123–144, 151–200.
B. Grammaticos, J. Moulin Ollagnier, A. Ramani, J.-M. Strelcyn andS. Wojciechowski,Integrals of quadratic ordinary differential equations in ℝ 3: the Lotka — Volterra system, Physica-A163 (1990), 683–722.
J.-P. Jouanolou,Equations de Pfaff algébriques, Lect. Notes in Math.708, Springer-Verlag, Berlin (1979).
A. Maciejewski, J. Moulin Ollagnier, A. Nowicki andJ.-M. Strelcyn,Around Jouanolou non-integrability theorem, Indagationes Mathematicae11, (2000), 239–254.
J. Moulin Ollagnier andJ.-M. Strelcyn,On first integrals of linear systems, Frobenius integrability theorem and linear representation of Lie algebras in Bifurcations of Planar Vector Fields, Proceedings, Luminy 1989, J.-P. Francoise and R. Roussarie (Eds.)Lecture Notes in Mathematics 1455, Springer-Verlag, Berlin, Heidelberg, New-York, Tokyo (1991), 243–271.
J. Moulin Ollagnier, A. Nowicki andJ.-M. Strelcyn,On the non-existence of constants of derivations: the proof of a theorem of Jouanolou and its development. Bull. Sci. math.119 (1995), 195–233.
J. Moulin Ollagnier,Algorithms and methods in differential algebra, Theoretical Computer Science157 (1996), 115–127.
J. Moulin Ollagnier,Liouvillian first integrals of homogeneous polynomial vector fields, Colloquium MathematicumLXX (1996), 195–217.
J. Moulin Ollagnier,Polynomial first integrals of the Lotka-Volterra system, Bull. Sci. math.121 (1997), 463–476.
J. Moulin Ollagnier,Hexagonal graphs in linear algebra, conference, (1998).
J. Moulin Ollagnier,Rational Integration of the Lotka-Volterra system. Bull. Sci. math.123 (1999), 437–466.
J. Moulin Ollagnier,About a conjecture on quadratic vector fields, to be published in Journal of Pure and Applied Algebra (June 2000).
J. Milnor,Singular points of complex hypersurfaces, Princeton University Press and the University of Tokyo Press, Princeton, New Jersey, 1968.
P. Painlevé,Œuvres, tomes 1–3, Ed. du CNRS, Paris, 1972, 1974, 1975.
P. Painlevé,Sur les intégrales rationnelles des équations différentielles du premier ordre. C. R. Acad. Sc. Paris110 (1890), 34–36; reprinted in Œuvres, t. 2, 220–222.
P. Painleve,Sur les intégrales algébriques des équations différentielles du premier ordre, C. R. Acad. Sc. Paris110 (1890), 945–948; reprinted in Œuvres, tome 2, 233–235.
P. Painlevé,Mémoire sur les équations différentielles du premier ordre, Ann. Ecole Norm. Sup. lère partie:8 (1891), 9–58, 103–140; 2ème partie:8 (1891), 201–226, 267–284 and9 (1891), 9–30; 3ème partie:9 (1892), 101–144, 283–308; reprinted in Œuvres, tome 2, 237–461.
P. Painlevé,Leçons sur la théorie analytique des équations différentielles professées à Stockholm (Septembre, Octobre, Novembre 1895), sur l'invitation de S. M. le Roi de Suéde et de Norvége, Ed. Hermann, Paris (1897), reprinted in Œuvres, tome 1, 205–800.
P. Painlevé,Mémoire sur les équations différentielles du premier ordre dont l'intégrale est de la forme h(x)(y-g 1(x))λ 1 (y-g 2(x))λ 2...(y-g 1(x))λ n=C, Ann. Fac. Sc. Univ., Toulouse (1896), 1–37; reprinted in Œuvres, tome 2, 546–582.
H. Poincaré,Sur l'intégration algébrique des équations différentielles, C. R. Acad. Sc. Paris112 (1891), 761–764; reprinted in Œuvres, tome III, 32–34, Gauthier-Villars, Paris (1965).
H. Poincare,Sur l'intégration algébrique des équations différentielles du premier ordre et du premier degré, Rendic. Circ. Matemm. Palermo5 (1891), 161–191; reprinted in Œuvres, tome III, 35–58, Gauthier-Villars, Paris (1965).
H. Poincaré,Sur l'intégration algébrique des équations différentielles du premier ordre et du premier degré, Rendic. Circ. Matem. Palermo11 (1897), 193–239; reprinted in Œuvres, tome III, 59–94, Gauthier-Villars, Paris (1965).
M. J. Prelle andM. F. Singer,Elementary first integrals of differential equations, Trans. Amer. Math. Soc.279 (1983), 215–229.
R. H. Risch,The problem of integration in finite terms, Trans. Amer. Math. Soc.139 (1969), 167–189.
M. Rosenlicht,On Liouville's theory of elementary functions, Pac. Jour. of Math.65 (1976), 485–492.
J.-P. Serre,Groupes algébriques et corps de classes, Hermann, Paris, 1959.
M. F. Singer,Liouvillian first integrals of differential equations, Trans. Amer. Math. Soc.333 (1992), 673–688.
J.-M. Strelcyn andS. Wojciechowski,A method of finding integrals of 3-dimensional dynamical systems, Phys. Letters133A (1988), 207–212.
Author information
Authors and Affiliations
Corresponding author
Additional information
Submitted by J. Llibre
Rights and permissions
About this article
Cite this article
Ollagnier, J.M. Liouvillian integration of the Lotka-Volterra system. Qual. Th. Dyn. Syst 2, 307–358 (2001). https://doi.org/10.1007/BF02969345
Issue Date:
DOI: https://doi.org/10.1007/BF02969345