Abstract
We present infinitely many solutions of the general Heun equation in terms of generalized hypergeometric functions. Each solution assumes that two restrictions are imposed on the involved parameters: acharacteristic exponent of one of the singularities must be a nonzero integer, and the accessory parameter must satisfy a polynomial equation.
Similar content being viewed by others
References
K. Heun, “Zur Theorie der Riemann’schen Functionen zweiter Ordnung mit vier Verzweigungspunkten,” Math. Ann., 33, 161–179 (1889).
A. Ronveaux, ed., Heun’s Differential Equations, Oxford Univ. Press, New York (1995).
S. Yu. Slavyanov and W. Lay, Special Functions, Oxford Univ. Press, Oxford (2000).
F. W. J. Olver, D. W. Lozier, R. F. Boisvert, and C. W. Clark, eds., NIST Handbook of Mathematical Functions, Cambridge Univ. Press, Cambridge (2010).
M. Hortaçsu, “Heun functions and some of their applications in physics,” Adv. High Energy Phys., 2018, 8621573 (2018).
The Heun Project, “Heun functions, their generalizations and applications,” http://theheunproject.org/bibliography.html (2019).
L. J. Slater, Generalized Hypergeometric Functions, Cambridge Univ. Press, Cambridge (1966).
J. Letessier, “Co-recursive associated Jacobi polynomials,” J. Comput. Appl. Math., 57, 203–213 (1995).
J. Letessier, G. Valent, and J. Wimp, “Some differential equations satisfied by hypergeometric functions,” in: Approximation and Computation: A Festschrift in Honor of Walter Gautschi (Intl. Ser. Numerical Math., Vol. 119, R. V. M. Zahar, ed.), Birkhäuser, Boston, Mass. (1994), pp. 371–381.
R. S. Maier, “P-symbols, Heun identities, and 3F2 identities,” in: Special Functions and Orthogonal Polynomials (Contemp. Math., Vol. 471, D. Dominici and R. S. Maier, eds.), Amer. Math. Soc., Providence, R. I. (2008), pp. 139–159.
K. Takemura, “Heun’s equation, generalized hypergeometric function, and exceptional Jacobi polynomial,” J. Phys. A: Math. Theor., 45, 085211 (2012); arXiv:1106.1543v3 [math.CA] (2011).
T. A. Ishkhanyan, T. A. Shahverdyan, and A. M. Ishkhanyan, “Expansions of the solutions of the general Heun equation governed by two-term recurrence relations for coefficients,” Adv. High Energy Phys., 2018, 4263678 (2018).
N. Svartholm, “Die Lösung der Fuchsschen Differentialgleichung zweiter Ordnung durch hypergeometrische Polynome,” Math. Ann., 116, 413–421 (1939).
A. Erdélyi, “Certain expansions of solutions of the Heun equation,” Quart. J. Math., Oxford Ser., os-15, 62–69 (1944).
D. Schmidt, “Die Lösung der linearen Differentialgleichung 2. Ordnung um zwei einfache Singularitäten durch Reihen nach hypergeometrischen Funktionen,” J. Reine Angew. Math., 309, 127–148 (1979).
A. M. Ishkhanyan, “Exact solution of the Schrödinger equation for a short-range exponential potential with inverse square root singularity,” Eur. Phys. J. Plus, 133, 83 (2018); arXiv:1803.00565v1 [quant-ph] (2018).
A. M. Ishkhanyan, “The third exactly solvable hypergeometric quantum-mechanical potential,” Europhys. Lett., 115, 20002 (2016); arXiv:1602.07685v1 [quant-ph] (2016).
A. M. Ishkhanyan, “Schrödinger potentials solvable in terms of the general Heun functions,” Ann. Phys., 388, 456–471 (2018).
V. Bargmann, “On the number of bound states in a central field of force,” Proc. Nat. Acad. Sci. USA, 38, 961–966 (1952).
F. Calogero, “Upper and lower limits for the number of bound states in a given central potential,” Commun. Math. Phys., 1, 80–88 (1965).
R. S. Maier, “On reducing the Heun equation to the hypergeometric equation,” J. Differ. Equ., 213, 171–203 (2005).
M. van Hoeij and R. Vidunas, “Belyi functions for hyperbolic hypergeometric-to-Heun transformations,” J. Algebra, 441, 609–659 (2015).
R. Vidunas and G. Filipuk, “Parametric transformations between the Heun and Gauss hypergeometric functions,” Funkcial. Ekvac., 56, 271–321 (2013).
R. Vidunas and G. Filipuk, “A classification of coverings yielding Heun-to-hypergeometric reductions,” Osaka J. Math., 51, 867–905 (2014).
A. Ya. Kazakov, “Euler integral symmetry and deformed hypergeometric equation,” J. Math. Sci. (N. Y.), 185, 573–580 (2012).
A. Ya. Kazakov, “Monodromy of Heun equations with apparent singularities,” Internat. J. Theor. Math. Phys., 3 (6), 190–196 (2013).
S. Yu. Slavyanov, D. F. Shat’ko, A. M. Ishkhanyan, and T. A. Rotinyan, “Generation and removal of apparent singularities in linear ordinary differential equations with polynomial coefficients,” Theor. Math. Phys., 189, 1726–1733 (2016).
S. Yu. Slavyanov, “Symmetries and apparent singularities for the simplest Fuchsian equations,” Theor. Math. Phys., 193, 1754–1760 (2017).
S. Yu. Slavyanov and O. L. Stesik, “Antiquantization of deformed Heun-class equations,” Theor. Math. Phys., 186, 118–125 (2016).
A. V. Shanin and R. V. Craster, “Removing false singular points as a method of solving ordinary differential equations,” Eur. J. Appl. Math., 13, 617–639 (2002).
E. S. Cheb-Terrab, “Solutions for the general, confluent, and biconfluent Heun equations and their connection with Abel equations,” J. Phys. A: Math. Theor., 37, 9923–9949 (2004); arXiv:math-ph/0404014v4 (2004).
A. Hautot, “Sur des combinaisons lineaires d’un nombre fini de fonctions transcendantes comme solutions d’equations différentielles du second ordre,” Bull. Soc. Roy. Sci. Liège, 40, 13–23 (1971).
R. V. Craster and V. H. Hoàng, “Applications of Fuchsian differential equations to free boundary problems,” Proc. Roy. Soc. London Ser. A, 454, 1241–1252 (1998).
H. V. Hoàng, J. M. Hill, and J. N. Dewynne, “Pseudo-steady-state solutions for solidification in a wedge,” IMA J. Appl. Math., 60, 109–121 (1998).
R. V. Craster, “The solution of a class of free boundary problems,” Proc. Roy. Soc. London Ser. A, 453, 607–630 (1997).
A. Fratalocchi, A. Armaroli, and S. Trillo, “Time-reversal focusing of an expanding soliton gas in disordered replicas,” Phys. Rev. A, 83, 053846 (2011); arXiv:1104.1886v1 [nlin.PS] (2011).
Q. T. Xie, “New quasi-exactly solvable periodic potentials,” J. Phys. A, 44, 285302 (2011).
A. M. Ishkhanyan, “Thirty five classes of solutions of the quantum time-dependent two-state problem in terms of the general Heun functions,” Eur. Phys. J. D, 69, 10 (2015); arXiv:1404.3922v2 [quant-ph] (2014).
G. S. Joyce and R. T. Delves, “Exact product forms for the simple cubic lattice Green function 11,” J. Phys. A: Math. Theor., 37, 5417–5447 (2004).
G. V. Kraniotis, “The Klein-Gordon-Fock equation in the curved spacetime of the Kerr-Newman (anti) de Sitter black hole,” Class. Q. Grav., 33, 225011 (2016).
Author information
Authors and Affiliations
Corresponding author
Ethics declarations
Conflicts of interest. The author declares no conflicts of interest.
Additional information
This research was supported by the Armenian State Committee of Science (SCS Grant Nos. 18RF-139 and 18T-1C276) and the Russian — Armenian (Slavonic) University at the expense of the Ministry of Education and Science of the Russian Federation.
Prepared from an English manuscript submitted by the author; for the Russian version, see Teoreticheskaya i Matematicheskaya Fizika, Vol. 202, No. 1, pp. 3–13, January, 2020.
Rights and permissions
About this article
Cite this article
Ishkhanyan, A.M. Generalized Hypergeometric Solutions of the Heun Equation. Theor Math Phys 202, 1–10 (2020). https://doi.org/10.1134/S0040577920010018
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1134/S0040577920010018