Abstract
The theory of slice regular functions of a quaternionic variable on the unit ball of the quaternions was introduced by Gentili and Struppa in 2006 and nowadays it is a well established function theory, especially in view of its applications to operator theory. In this paper, we introduce the notion of fractional slice regular functions of a quaternionic variable defined as null-solutions of a fractional Cauchy–Riemann operators. We present a fractional Cauchy–Riemann operator in the sense of Riemann–Liouville and then in the sense of Caputo, with orders associated to an element of \((0,1)\times {\mathbb {R}} \times (0,1)\times {\mathbb {R}}\) for some axially symmetric slice domains which are new in the literature. We prove a version of the representation theorem, of the splitting lemma and we discuss a series expansion.
Similar content being viewed by others
Availability of data and materials
Not applicable.
Code availability
Not applicable.
References
Alpay, D., Colombo, F., Sabadini, I.: Slice hyperholomorphic Schur analysis. Oper. Theory Adv. Appl. 256 (2016)
Baleanu, D., Restrepo, J.E., Suragan, D.: A class of time-fractional Dirac type operators. Chaos Solitons Fractals 143, 15 (2021)
Bernstein, S.: A fractional Dirac operator. Oper. Theory Adv. Appl. 252, 27–41 (2016)
Cerroni, C.: From the theory of congeneric surd equations to Segre’s bicomplex numbers. Hist. Math. 44(3), 232–251 (2017)
Coloma, N., Di Teodoro, A., Ochoa-Tocachi, D., et al.: Fractional elementary bicomplex functions in the Riemann–Liouville sense. Adv. Appl. Clifford Algebras 31(4), 29–63 (2021)
Colombo, F., Gantner, J.: Quaternionic closed operators, fractional powers and fractional diffusion processes. Oper. Theory Adv. Appl. 274(2), 1045–1100 (2016)
Colombo, F., Gantner, J.: Fractional powers of quaternionic operators and Kato’s formula using slice hyperholomorphicity. Trans. Am. Math. Soc. 370(2), 1045–1100 (2018)
Colombo, F., Sabadini, I., Struppa, D.C.: Noncommutative Functional Calculus. Theory and Applications of Slice Hyperholomorphic Functions. Birkhauser, Basel (2011)
Colombo, F., Sabadini, I., Struppa, D.C.: Entire Slice Regular Functions. Springer Briefs in Mathematics. Springer, Boston (2016)
Contharteze Grigoletto, E., Capelas de Oliveira, E.: Fractional versions of the fundamental theorem of calculus. Appl. Math. 4(3), 23–33 (2013)
Delgado, B., Macías-Díaz, J.: On the general solutions of some non-homogeneous div-curl systems with Riemann–Liouville and Caputo fractional derivatives. Fractal Fract. 3(3), 1045–1100 (2021)
Dou, X., Jin, M., Ren, G., et al.: A new approach to slice analysis via slice topology. Adv. Appl. Clifford Algebras 31(5), 1045–1100 (2021)
Dou, X., Ren, G., Sabadini, I.: Extension theorem and representation formula in non-axially symmetric domains for slice regular functions. J. Eur. Math. Soc. 31(5), 1045–1100 (2021)
Ferreira, M., Vieira, N.: Eigenfunctions and fundamental solutions of the fractional Laplace and Dirac operators: the Riemann–Liouville case. Complex Anal. Oper. Theory 10(5), 1081–1100 (2016)
Ferreira, M., Vieira, N.: Eigenfunctions and fundamental solutions of the fractional Laplace and Dirac operators using Caputo derivatives. Complex Var. Elliptic Equ. 62(9), 1237–1253 (2017)
Ferreira, M., Krausshar, R.S., Rodrigues, M.M., et al.: A higher dimensional fractional Borel–Pompeiu formula and a related hypercomplex fractional operator calculus. Math. Methods Appl. Sci. 42(10), 3633–3653 (2019)
Gentili, G., Stoppato, C.: A local representation formula for quaternionic slice regular functions. Proc. Am. Math. Soc. 149(5), 2025–2034 (2021)
Gentili, G., Struppa, D.C.: A new theory of regular function of a quaternionic variable. Adv. Math. 216(9), 279–301 (2007)
Gentili, G., Stoppato, C., Struppa, D.C.: Regular Functions of a Quaternionic Variable. Springer Monographs in Mathematics, vol. 149(5), pp. 2025–2034. Springer (2013)
González-Cervantes, J.O., Bory-Reyes, J.: A quaternionic fractional Borel–Pompeiu type formula. Fractal 30(1), 2025–2034 (2022)
González-Cervantes, J.O., Bory-Reyes, J.: A bicomplex \((\vartheta ,\varphi )-\)weighted fractional Borel–Pompeiu type formula. J. Math. Anal. Appl. 520(2), 2025–2034 (2023)
Kähler, U., Vieira, N.: Fractional Clifford analysis. In: Hypercomplex Analysis: New Perspectives and Applications. Trends in Mathematics, vol. 520(2), pp. 191–201 (2014)
Kilbas, A.A., Srivastava, H.M., Trujillo, J.J.: Theory and Applications of Fractional Differential Equations. Hypercomplex Analysis: New Perspectives and Applications. Trends in Mathematics. North-Holland Mathematics Studies, vol. 204. Elsevier, Amsterdam (2006)
Leibniz, G.W.: TMathematische Schriften: aus den Handschriften der Königlichen Bibliothek zu Hannover. Briefwechsel zwischen Leibniz, Wallis, Varignon, Guido Grandi, Zendrini, Hermann und Freiherrn von Tschirnhaus, vol. 1. Druck und Verlag von H.W. Schmidt. Halle, Germany (1859)
Liouville, J.: Mémoire sur le calcul des différentielles a indices quelconques. J. Ecole Polytech. 13(2), 71–162 (1832)
Miller, K.S., Ross, B.: An Introduction to the Fractional Calculus and Fractional Differential Equations. Wiley, New York (1993)
Oldham, K.B., Spanier, J.: The Fractional Calculus. Dover Publications, New York (2006)
Ortigueira, M.D.: Fractional Calculus for Scientists and Engineers. Lecture Notes in Electrical Engineering, vol. 84. Springer, Dordrecht (2011)
Peña Pérez, Y., Abreu Blaya, R., Árciga Alejandre, M.P., et al.: Biquaternionic reformulation of a fractional monochromatic Maxwell system. Adv. High Energy Phys. 13(2), 71–162 (2020)
Podlubny, I.: Fractional differential equations. An introduction to fractional derivatives, fractional differential equations, to methods of their solution and some of their applications. Mathematics in Science and Engineering, vol. 198. Academic Press, San Diego (1999)
Riemann, B.: Versuch einer allgemeinen Auffassung der Integration und Differentiation (An attempt to a general understanding of integration and differentiation) (1847) In: Weber, H. (ed.), Bernhard Riemanns gesammelte mathematische Werke und wissenschaftlicher Nachlass. Dover Publications, Germany (1953)
Ross, B.: A brief history and exposition of the fundamental theory of fractional calculus. In: Ross, B. (ed.) Fractional Calculus and Its Applications. Lecture Notes in Mathematics, vol. 457. Springer, Berlin (1975)
Samko, S., Kilbas, A.A., Marichev, O.: Fractional Integrals and Derivatives, Theory and Applications. Gordon and Breach Science Publlication, London (1993)
Tarasov, V.E.: No violation of the Leibniz rule. No VTRMB fractional derivative. Commun. Nonlinear Sci. Numer. Simul. 18(11), 2945–2948 (2013)
Valério, D., Trujillo, J.J., Rivero, M., et al.: Fractional calculus: a survey of useful formulas. Eur. Phys. J. Spec. Top. 222(11), 1827–1846 (2013)
Vieira, N.: Fischer decomposition and Cauchy–Kovalevskaya extension in fractional Clifford analysis: the Riemann–Liouville case. Proc. Edinb. Math. Soc. II 60(1), 251–272 (2017)
Funding
This work was partially supported by Instituto Politécnico Nacional (Grant Numbers SIP20232103, SIP20230312) and CONACYT.
Author information
Authors and Affiliations
Contributions
All authors contributed equally to the study, read and approved the final version of the submitted manuscript.
Corresponding author
Ethics declarations
Conflict of interest
The authors declare that they have no competing interests regarding the publication of this paper.
Additional information
Publisher's Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Rights and permissions
Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.
About this article
Cite this article
González-Cervantes, J.O., Bory-Reyes, J. & Sabadini, I. Fractional Slice Regular Functions of a Quaternionic Variable. Results Math 79, 32 (2024). https://doi.org/10.1007/s00025-023-02047-6
Received:
Accepted:
Published:
DOI: https://doi.org/10.1007/s00025-023-02047-6
Keywords
- Quaternionic analysis
- Cauchy–Riemann operator
- slice regular functions
- Riemann–Liouville and Caputo derivatives