Advances in Differential Equations

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Advances in Differential Equations
Volume 30, Numbers 5-6, May/June 2025



To appear in the next issue
Volume 30, Numbers 7-8, July/August 2025


    Bifurcation results for nonlinear eigenvalue problems involving the $(p,q)$-Laplace operator
    Emmanuel Wend-Benedo Zongo and Bernhard Ruf
    Advances in Differential Equations, Volume 30, Number 7/8 (2025), 421-454
    Abstract: In this paper, we analyze an eigenvalue problem for nonlinear elliptic operators involving homogeneous Dirichlet boundary conditions in an open smooth bounded domain. We prove bifurcation results from trivial solutions and from infinity for considered nonlinear eigenvalue problem. We also show the existence of multiple solutions of the nonlinear problem using variational methods.



    The defocusing nonlinear Schrödinger equation with step-like oscillatory initial data
    Samuel Fromm, Jonatan Lenells, and Ronald Quirchmayr
    Advances in Differential Equations, Volume 30, Number 7/8 (2025), 455-525
    Abstract: We study the Cauchy problem for the defocusing nonlinear Schrödinger (NLS) equation under the assumption that the solution vanishes as $x \to \infty$ and approaches an oscillatory plane wave as $x \to -\infty$. We first develop an inverse scattering transform formalism for solutions satisfying such step-like boundary conditions. Using this formalism, we prove that there exists a global solution of the corresponding Cauchy problem and establish a representation for this solution in terms of the solution of a Riemann--Hilbert problem. By performing a steepest descent analysis of this Riemann--Hilbert problem, we identify three asymptotic sectors in the half-plane $t\ge0$ of the $xt$-plane and derive asymptotic formulas for the solution in each of these sectors. Finally, by restricting the constructed solutions to the half-line $x \ge 0$, we find a class of solutions with asymptotically time-periodic boundary values previously sought for in the context of the NLS half-line problem.


    The well-posedness of the stochastic nonlinear Schrödinger equations in $H^2(R^d)$
    Isamu Dôku, Shunya Hashimoto, and Shuji Machihara
    Advances in Differential Equations, Volume 30, Number 7/8 (2025), 527-560
    Abstract: The Cauchy problem for the stochastic nonlinear Schrödinger equation with multiplicative noise is considered where the nonlinear term is of power type and the noise coefficients are purely imaginary numbers. The main purpose of this paper is to construct classical solutions in $H^2(\mathbb{R}^d)$ for the problem. The techniques of Kato [21, 22] work well in overcoming smoothness problems even for the stochastic equations.

    Multi-bump solutions for the double phase critical Schrödinger equations involving logarithmic nonlinearity
    Lifeng Guo, Sihua Liang, Bohui Lin, and Patrizia Pucci
    Advances in Differential Equations, Volume 30, Number 7/8 (2025), 561-600
    Abstract: In this paper, we consider the existence and multiplicity of multi-bump solutions for the following double phase critical Schrödinger equations with logarithmic nonlinearity in $\mathbb{R}^N$ \begin{equation}\label{E} \begin{cases} -\Delta_pu-\Delta_qu+(\lambda\mathcal {V}(x) +\mathcal {Z}(x))(|u|^{p-2}u+|u|^{q-2}u) \\ \qquad\qquad\qquad\qquad\qquad\qquad =\alpha |u|^{p-2}u\log |u|^p+|u|^{p^\ast-2}u, \\ u\in W^{1,p}(\mathbb{R}^N)\bigcap W^{1,q} (\mathbb{R}^N), \end{cases} \tag{$\mathcal E$} \end{equation} where $N\geq3, \alpha\in (1, \infty), \Delta_\wp u=$div$(|\nabla|^{\wp-2}\nabla u)$ is the $\wp$-Laplacian operator with $\wp\in\{p,q\}$, $0 < q < p < p^\ast,$ the parameter $\lambda\geq1$ and $ \mathcal {Z},\, \mathcal {V}: \mathbb{R}^N \rightarrow \mathbb{R}$ are nonnegative continuous functions. Applying variational methods, we prove {the} existence of at least $2^k-1$ multi-bump solutions of \eqref{E} as $\lambda\geq1$ is sufficiently large. The main features and novelty of the paper are the presence of the double phase operator and of the logarithmic nonlinearity. Moreover, these results are new even in the case $p = q =2$. In a sense, we fill in the blanks of previous papers in the subject.



To appear in the next issue
Volume 30, Numbers 9-10, September/October 2025


    Energy decay for semilinear evolution equations with memory and time-dependent time delay feedback
    Elisa Continelli and Cristina Pignotti
    Advances in Differential Equations, Volume 30, Number 9/10 (2025), 601-634
    Abstract: In this paper, we study well-posedness and exponential stability for semilinear second-order evolution equations with memory and time-varying delay feedback. The time delay function is assumed to be continuous and bounded. Under a suitable assumption on the delay feedback, we are able to prove that solutions corresponding to small initial data are globally defined and satisfy an exponential decay estimate.


    Singular elliptic equations having a gradient term with natural growth
    Adele Ferone, Anna Mercaldo, and Sergio Segura de Leon
    Advances in Differential Equations, Volume 30, Number 9/10 (2025), 635-670
    Abstract: We study a class of Dirichlet boundary value problems whose prototype is \begin{equation}\label{1.2abs} \left\{\begin{array}{ll} -\Delta_p u =h(u)|\nabla u|^p+u^{q-1}+f(x)\, &\quad\hbox{in } \ \Omega\,,\\ u\ge 0\,,&{\quad\hbox{in } \ \Omega}\\ u = 0\, &\quad\hbox{on }\partial \Omega\,, \end{array}\right. \end{equation} where $\Omega$ an open bounded subset of $\mathbb{R}^N$, $0 < q < 1$, $1 < p < N$, $h$ is a continuous function and $f$ belongs to a suitable Lebesgue space. The main features of this problem are the presence of a singular term and a first order term with natural growth in the gradient. A priori estimates and existence results are proved depending on the summability of the datum $f$.


    On the Föppl-von Kármán theory for elastic prestrained films with varying thickness
    Hui Li
    Advances in Differential Equations, Volume 30, Number 9/10 (2025), 671-706
    Abstract: We derive the variational limiting theory of thin films, parallel to the Föppl-von Kármán theory in the nonlinear elasticity, for films that have been prestrained and whose thickness is a general non-constant function. Using $\Gamma$-convergence, we extend the existing results to the variable thickness setting, calculate the associated Euler-Lagrange equations of the limiting energy, and analyze convergence of equilibria. The resulting formulas display the interrelation between deformations of the geometric mid-surface and components of the growth tensor.


    Maximal regularity for degenerate multi-term fractional integro-differential equations and applications
    Rafael Aparicio and Valentin Keyantuo
    Advances in Differential Equations, Volume 30, Number 9/10 (2025), 707-758
    Abstract: Many problems in the applied sciences can be formulated as multi-term differential or integro-differential equations. We use the theory of operator-valued Fourier multipliers to obtain characterizations for well-posedness of degenerate multi-term fractional differential equations with infinite delay in Banach spaces. We adopt the right-sided Liouville fractional derivative on the real axis and the Lebesgue-Bochner spaces $L^p(\mathbb{R},X), \, 1\le p < \infty$ where $X$ is a Banach space. When $X$ is a UMD (Banach space in which martingale differences are unconditional) and $1 < p < \infty$, concrete conditions are given for well-posedness using the concept of $\mathcal{R}$-boundedness. Applications are given for concrete integro-differential equations which appear in several models in the applied sciences, particularly physics, biological sciences, rheology, and material science. We present several concrete examples of equations that can be treated by the results obtained. The equations considered in the applications can contain fractional derivatives in the space variable.

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