Existence of weak solutions to boundary problem for elliptic equations with variable exponents under $p\left(\cdot \right)$-uniformly convexity condition

Document Type : Research Paper

Author
National Technical University of Ukraine, ”Igor Sikorsky Kyiv Polytechnic Institute” Kyiv, Ukraine, 37, Prospect Beresteiskyi (former Peremohy), Kyiv, Ukraine, 03056
Abstract
The main goal of this work is to establish the existence of a weak solution in {{$W_{1,0}^{p\left(\cdot \right)} \left(\Omega \right)$}} to the boundary problem
\[\begin{array}{l} {-div\left(a\left(x,\; \nabla u\right)\right)+d\left(x\right)u\left|u\right|^{p\left(x\right)-2} =f\left(x,\; u\right),} \\ {\left. u\right|_{\partial \Omega } =0,} \end{array}\]
where $\Omega $ is a bounded domain in \textit{$R^{n} ,\; n\ge 3$}. The main term $a\left(x,\; \xi \right)=\frac{\partial A\left(x,\; \xi \right)}{\partial \xi } $ satisfies: $p\left(\cdot \right)$-uniformly convexity and $p\left(\cdot \right)$- sub-homogeneousness conditions; $d\in L^{\infty } \left(\Omega \right)$ and $d_{m} >0$; and $f$ is a real Caratheodory function on $\Omega \times R$, which satisfies the following non-standard growth condition {{$\left|f\left(x,\; s\right)\right|\le A_{1} \left(1+\left|s\right|^{\gamma \left(x\right)-1} \right)$}}, where {{$p_{S} <\gamma _{m} \le \gamma _{S} <p_{m}^{*} $}}, {{$c_{1} $}} is a positive constant, and $p^{*} \left(x\right)=\frac{np\left(x\right)}{n-p\left(x\right)} $ for $p\left(x\right)<n$.
Keywords

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Articles in Press, Corrected Proof
Available Online from 25 August 2026

  • Receive Date 16 November 2025
  • Revise Date 08 December 2025
  • Accept Date 11 December 2025