摘要: 为了从根本上消灭存在于数学基础中的各种悖论,使数学建筑在高度可靠的基础上,发现形式逻辑只能用于同一律,矛盾律和排中律这三大规律都成立的讨论域 (称为可行域) 内,否则就会产生包括悖论在内的各种错误,而在形式逻辑的适用范围即可行域内,只要前提可靠,推导严格,悖论是不存在的。根据该结论,分析了说谎者悖论和理发师悖论等一些历史上比较著名的悖论的形成原因,同时指出了数学基础中皮亚诺公理的应用和康托尔定理、区间套和对角线法证明中的一些逻辑错误,提出了能够避免这些错误的统一的定义自然数、有理数和无理数的建议。
分类: 数学 >> 数学(综合) 提交时间: 2018-09-23
摘要: The aim of this paper is to study the heterogeneous optimization problem \begin{align*} \mathcal {J}(u)=\int_{\Omega}(G(|\nabla u|)+qF(u^+)+hu+\lambda_{+}\chi_{\{u>0\}} )\text{d}x\rightarrow\text{min}, \end{align*} in the class of functions $ W^{1,G}(\Omega)$ with $ u-\varphi\in W^{1,G}_{0}(\Omega)$, for a given function $\varphi$, where $W^{1,G}(\Omega)$ is the class of weakly differentiable functions with $\int_{\Omega}G(|\nabla u|)\text{d}x0$ respectively. We also establish growth rate near the free boundary for each non-negative minimizer of $\mathcal {J}(u)$ with $\lambda_+=0$, and $\lambda_+>0$ respectively. Furthermore, under additional assumption that $F\in C^1([0,+\infty); [0,+\infty))$, local Lipschitz regularity is carried out for non-negative minimizers of $\mathcal {J}(u)$ with $\lambda_{+}>0$.
分类: 数学 >> 数学(综合) 提交时间: 2018-09-22
摘要: In this paper, we prove several regularity results for the heterogeneous, two-phase free boundary problems $\mathcal {J}_{\gamma}(u)=\int_{\Omega}\big(f(x,\nabla u)+(\lambda_{+}(u^{+})^{\gamma}+\lambda_{-}(u^{-})^{\gamma})+gu\big)\text{d}x\rightarrow \text{min}$ under non-standard growth conditions. Included in such problems are heterogeneous jets and cavities of Prandtl-Batchelor type with $\gamma=0$, chemical reaction problems with $0 2$ for $p-$Laplace equations, but also in the singular case of $1
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分类: 数学 >> 数学(综合) 提交时间: 2018-09-22
摘要: We establish regularity of solutions to the $G$-Laplace equation $-\text{div}\ \bigg(\frac{g(|\nabla u|)}{|\nabla u|}\nabla u\bigg)=\mu$, where $\mu$ is a nonnegative Radon measure satisfying $\mu (B_{r}(x_{0}))\leq Cr^{m}$ for any ball $B_{r}(x_{0})\subset\subset \Omega$ with $r\leq 1$ and $m>n-1-\delta\geq 0$. The function $g(t)$ is supposed to be nonnegative and $C^{1}$-continuous in $[0,+\infty)$, satisfying $g(0)=0$, and for some positive constants $\delta$ and $g_{0}$, $\delta\leq \frac{tg'(t)}{g(t)}\leq g_{0}, \forall t>0$, that generalizes the structural conditions of Ladyzhenskaya-Ural'tseva for an elliptic operator.
分类: 数学 >> 数学(综合) 提交时间: 2018-09-22
摘要: Explicit equations are obtained to convert Cartesian coordinates to elliptic coordinates, based on which an elliptic-coordinate function can be readily mapped on a uniform Cartesian mesh.Application to Kirchhoff vortex is provided.
分类: 数学 >> 数学(综合) 提交时间: 2018-09-18
摘要: 本文研究一类高阶非线性微分方程的Lyapunov 不等式,是对《Lyapunov-type inequalities for $\psi$-Laplacian equations》有关结论的进一步探讨和推广
分类: 数学 >> 数学(综合) 提交时间: 2018-09-13
摘要: The aim of this paper is to study the obstacle problem associated with an elliptic operator having degenerate coercivity, and with a low order term and $L^1-$data. We prove the existence of an entropy solution to the obstacle problem and show its continuous dependence on the $L^{1}-$data in $W^{1,q}(\Omega)$ with some $q>1$.