{"publication_status":"published","doi":"10.1007/s10884-022-10167-w","date_created":"2024-04-07T12:39:12Z","status":"public","_id":"53323","user_id":"31496","publication_identifier":{"issn":["1040-7294","1572-9222"]},"author":[{"full_name":"Winkler, Michael","last_name":"Winkler","first_name":"Michael"}],"year":"2022","keyword":["Analysis"],"type":"journal_article","publisher":"Springer Science and Business Media LLC","citation":{"short":"M. Winkler, Journal of Dynamics and Differential Equations (2022).","bibtex":"@article{Winkler_2022, title={Slow Grow-up in a Quasilinear Keller–Segel System}, DOI={10.1007/s10884-022-10167-w}, journal={Journal of Dynamics and Differential Equations}, publisher={Springer Science and Business Media LLC}, author={Winkler, Michael}, year={2022} }","ieee":"M. Winkler, “Slow Grow-up in a Quasilinear Keller–Segel System,” Journal of Dynamics and Differential Equations, 2022, doi: 10.1007/s10884-022-10167-w.","ama":"Winkler M. Slow Grow-up in a Quasilinear Keller–Segel System. Journal of Dynamics and Differential Equations. Published online 2022. doi:10.1007/s10884-022-10167-w","mla":"Winkler, Michael. “Slow Grow-up in a Quasilinear Keller–Segel System.” Journal of Dynamics and Differential Equations, Springer Science and Business Media LLC, 2022, doi:10.1007/s10884-022-10167-w.","chicago":"Winkler, Michael. “Slow Grow-up in a Quasilinear Keller–Segel System.” Journal of Dynamics and Differential Equations, 2022. https://doi.org/10.1007/s10884-022-10167-w.","apa":"Winkler, M. (2022). Slow Grow-up in a Quasilinear Keller–Segel System. Journal of Dynamics and Differential Equations. https://doi.org/10.1007/s10884-022-10167-w"},"language":[{"iso":"eng"}],"date_updated":"2024-04-07T12:39:17Z","title":"Slow Grow-up in a Quasilinear Keller–Segel System","abstract":[{"text":"AbstractIn a ball $$\\Omega =B_R(0)\\subset \\mathbb {R}^n$$\r\n \r\n Ω\r\n =\r\n \r\n B\r\n R\r\n \r\n \r\n (\r\n 0\r\n )\r\n \r\n ⊂\r\n \r\n \r\n R\r\n \r\n n\r\n \r\n \r\n , $$n\\ge 2$$\r\n \r\n n\r\n ≥\r\n 2\r\n \r\n , the chemotaxis system $$\\begin{aligned} \\left\\{ \\begin{array}{l}u_t = \\nabla \\cdot \\big ( D(u) \\nabla u \\big ) - \\nabla \\cdot \\big ( uS(u)\\nabla v\\big ), \\\\ 0 = \\Delta v - \\mu + u, \\qquad \\mu =\\frac{1}{|\\Omega |} \\int _\\Omega u, \\end{array} \\right. \\qquad \\qquad (\\star ) \\end{aligned}$$\r\n \r\n \r\n \r\n \r\n \r\n \r\n \r\n \r\n \r\n \r\n \r\n \r\n u\r\n t\r\n \r\n =\r\n ∇\r\n ·\r\n \r\n (\r\n \r\n D\r\n \r\n (\r\n u\r\n )\r\n \r\n ∇\r\n u\r\n \r\n )\r\n \r\n -\r\n ∇\r\n ·\r\n \r\n (\r\n \r\n u\r\n S\r\n \r\n (\r\n u\r\n )\r\n \r\n ∇\r\n v\r\n \r\n )\r\n \r\n ,\r\n \r\n \r\n \r\n \r\n \r\n \r\n \r\n 0\r\n =\r\n Δ\r\n v\r\n -\r\n μ\r\n +\r\n u\r\n ,\r\n \r\n μ\r\n =\r\n \r\n 1\r\n \r\n |\r\n Ω\r\n |\r\n \r\n \r\n \r\n ∫\r\n Ω\r\n \r\n u\r\n ,\r\n \r\n \r\n \r\n \r\n \r\n \r\n \r\n \r\n \r\n (\r\n ⋆\r\n )\r\n \r\n \r\n \r\n \r\n \r\n \r\n is considered under no-flux boundary conditions, with a focus on nonlinearities $$S\\in C^2([0,\\infty ))$$\r\n \r\n S\r\n ∈\r\n \r\n C\r\n 2\r\n \r\n \r\n (\r\n \r\n [\r\n 0\r\n ,\r\n ∞\r\n )\r\n \r\n )\r\n \r\n \r\n which exhibit super-algebraically fast decay in the sense that with some $$K_S>0, \\beta \\in [0,1)$$\r\n \r\n \r\n K\r\n S\r\n \r\n >\r\n 0\r\n ,\r\n β\r\n ∈\r\n \r\n [\r\n 0\r\n ,\r\n 1\r\n )\r\n \r\n \r\n and $$\\xi _0>0$$\r\n \r\n \r\n ξ\r\n 0\r\n \r\n >\r\n 0\r\n \r\n , $$\\begin{aligned} S(\\xi )>0 \\quad \\text{ and } \\quad S'(\\xi ) \\le -K_S\\xi ^{-\\beta } S(\\xi ) \\qquad \\text{ for } \\text{ all } \\xi \\ge \\xi _0. \\end{aligned}$$\r\n \r\n \r\n \r\n \r\n \r\n S\r\n \r\n (\r\n ξ\r\n )\r\n \r\n >\r\n 0\r\n \r\n \r\n and\r\n \r\n \r\n \r\n S\r\n ′\r\n \r\n \r\n (\r\n ξ\r\n )\r\n \r\n ≤\r\n -\r\n \r\n K\r\n S\r\n \r\n \r\n ξ\r\n \r\n -\r\n β\r\n \r\n \r\n S\r\n \r\n (\r\n ξ\r\n )\r\n \r\n \r\n \r\n for\r\n \r\n \r\n all\r\n \r\n ξ\r\n ≥\r\n \r\n ξ\r\n 0\r\n \r\n .\r\n \r\n \r\n \r\n \r\n \r\n It is, inter alia, shown that if furthermore $$D\\in C^2((0,\\infty ))$$\r\n \r\n D\r\n ∈\r\n \r\n C\r\n 2\r\n \r\n \r\n (\r\n \r\n (\r\n 0\r\n ,\r\n ∞\r\n )\r\n \r\n )\r\n \r\n \r\n is positive and suitably small in relation to S by satisfying $$\\begin{aligned} \\frac{\\xi S(\\xi )}{D(\\xi )} \\ge K_{SD}\\xi ^\\lambda \\qquad \\text{ for } \\text{ all } \\xi \\ge \\xi _0 \\end{aligned}$$\r\n \r\n \r\n \r\n \r\n \r\n \r\n \r\n ξ\r\n S\r\n (\r\n ξ\r\n )\r\n \r\n \r\n D\r\n (\r\n ξ\r\n )\r\n \r\n \r\n ≥\r\n \r\n K\r\n \r\n SD\r\n \r\n \r\n \r\n ξ\r\n λ\r\n \r\n \r\n \r\n for\r\n \r\n \r\n all\r\n \r\n ξ\r\n ≥\r\n \r\n ξ\r\n 0\r\n \r\n \r\n \r\n \r\n \r\n \r\n with some $$K_{SD}>0$$\r\n \r\n \r\n K\r\n \r\n SD\r\n \r\n \r\n >\r\n 0\r\n \r\n and $$\\lambda >\\frac{2}{n}$$\r\n \r\n λ\r\n >\r\n \r\n 2\r\n n\r\n \r\n \r\n , then throughout a considerably large set of initial data, ($$\\star $$\r\n ⋆\r\n ) admits global classical solutions (u, v) fulfilling $$\\begin{aligned} \\frac{z(t)}{C} \\le \\Vert u(\\cdot ,t)\\Vert _{L^\\infty (\\Omega )} \\le Cz(t) \\qquad \\text{ for } \\text{ all } t>0, \\end{aligned}$$\r\n \r\n \r\n \r\n \r\n \r\n \r\n \r\n z\r\n (\r\n t\r\n )\r\n \r\n C\r\n \r\n ≤\r\n \r\n \r\n ‖\r\n u\r\n \r\n (\r\n ·\r\n ,\r\n t\r\n )\r\n \r\n ‖\r\n \r\n \r\n \r\n L\r\n ∞\r\n \r\n \r\n (\r\n Ω\r\n )\r\n \r\n \r\n \r\n ≤\r\n C\r\n z\r\n \r\n (\r\n t\r\n )\r\n \r\n \r\n \r\n for\r\n \r\n \r\n all\r\n \r\n t\r\n >\r\n 0\r\n ,\r\n \r\n \r\n \r\n \r\n \r\n with some $$C=C^{(u,v)}\\ge 1$$\r\n \r\n C\r\n =\r\n \r\n C\r\n \r\n (\r\n u\r\n ,\r\n v\r\n )\r\n \r\n \r\n ≥\r\n 1\r\n \r\n , where z denotes the solution of $$\\begin{aligned} \\left\\{ \\begin{array}{l}z'(t) = z^2(t) \\cdot S\\big ( z(t)\\big ), \\qquad t>0, \\\\ z(0)=\\xi _0, \\end{array} \\right. \\end{aligned}$$\r\n \r\n \r\n \r\n \r\n \r\n \r\n \r\n \r\n \r\n \r\n \r\n z\r\n ′\r\n \r\n \r\n (\r\n t\r\n )\r\n \r\n =\r\n \r\n z\r\n 2\r\n \r\n \r\n (\r\n t\r\n )\r\n \r\n ·\r\n S\r\n \r\n (\r\n \r\n z\r\n \r\n (\r\n t\r\n )\r\n \r\n \r\n )\r\n \r\n ,\r\n \r\n t\r\n >\r\n 0\r\n ,\r\n \r\n \r\n \r\n \r\n \r\n \r\n \r\n z\r\n \r\n (\r\n 0\r\n )\r\n \r\n =\r\n \r\n ξ\r\n 0\r\n \r\n ,\r\n \r\n \r\n \r\n \r\n \r\n \r\n \r\n \r\n \r\n \r\n which is seen to exist globally, and to satisfy $$z(t)\\rightarrow +\\infty $$\r\n \r\n z\r\n (\r\n t\r\n )\r\n →\r\n +\r\n ∞\r\n \r\n as $$t\\rightarrow \\infty $$\r\n \r\n t\r\n →\r\n ∞\r\n \r\n . As particular examples, exponentially and doubly exponentially decaying S are found to imply corresponding infinite-time blow-up properties in ($$\\star $$\r\n ⋆\r\n ) at logarithmic and doubly logarithmic rates, respectively.","lang":"eng"}],"publication":"Journal of Dynamics and Differential Equations"}