Abstract
In this research, we present necessary and sufficient conditions for the existence and uniqueness of positive solutions for a class of Hilfer–Hadamard-type fractional differential equations with boundary value problems, including those with integral boundary conditions. The obtained results are conditional on a specific set of strong assumptions, which substantially narrow the class of admissible nonlinearities, coefficients, and boundary data. Thus, the present work extends the Hadamard-type framework to the Hilfer–Hadamard setting only within this restrictive regime, rather than providing a full extension to all Hilfer–Hadamard systems. We utilize the properties of (Formula presented.) -concave and sub-homogeneous operators along with two Banach fixed point theorems to achieve our results. An illustrative example is also provided to demonstrate the applicability of the methodology and highlight the main findings. The novelty of our work in this paper is twofold: First, we have expanded the scope by considering Hilfer–Hadamard-type fractional differential equations. Second, we employed a new fixed point theorem to improve our results within this particular framework.
Recommended Citation
H. Rasouli et al., "Existence And Uniqueness Of Positive Solutions For Hilfer–Hadamard-Type Fractional Differential Equations With Γ-Concave And Sub-Homogeneous Operators," Fractal and Fractional, vol. 10, no. 7, article no. 449, MDPI, Jul 2026.
The definitive version is available at https://doi.org/10.3390/fractalfract10070449
Department(s)
Mathematics and Statistics
Publication Status
Open Access
Keywords and Phrases
Green function; Hilfer–Hadamard-type fractional differential equation; positive solution; γ-concave and sub-homogeneous operator
International Standard Serial Number (ISSN)
2504-3110
Document Type
Article - Journal
Document Version
Final Version
File Type
text
Language(s)
English
Rights
© 2026 The Authors, All rights reserved.
Creative Commons Licensing

This work is licensed under a Creative Commons Attribution 4.0 License.
Publication Date
01 Jul 2026
