Abstract
In this paper, we review several results from singularly perturbed differential equations with multiple small parameters. In addition, we develop a general conceptual framework to compare and contrast the different results by proposing a three-step process. First, one specifies the setting and restrictions of the differential equation problem to be studied and identifies the relevant small parameters. Second, one defines a notion of equivalence via a property/observable for partitioning the parameter space into suitable regions near the singular limit. Third, one studies the possible asymptotic singular limit problems as well as perturbation results to complete the diagrammatic subdivision process. We illustrate this approach for two simple problems from algebra and analysis. Then we proceed to the review of several modern double-limit problems including multiple time scales, stochastic dynamics, spatial patterns, and network coupling. For each example, we illustrate the previously mentioned three-step process and show that already double-limit parametric diagrams provide an excellent unifying theme. After this review, we compare and contrast the common features among the different examples. We conclude with a brief outlook, how our methodology can help to systematize the field better, and how it can be transferred to a wide variety of other classes of differential equations.
Original language | English |
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Article number | 133105 |
Pages (from-to) | 1-26 |
Number of pages | 26 |
Journal | Physica D: Nonlinear Phenomena |
Volume | 431 |
Early online date | 1 Dec 2021 |
DOIs | |
Publication status | Published - Mar 2022 |
Bibliographical note
Funding Information:CK has been supported by a Lichtenberg Professorship of the VolkswagenStiftung. CK also acknowledges inspiring discussions with Grigorios A. Pavliotis regarding limit problems in differential equations, which were made possible by a TUM John von Neumann Visiting Professorship. NB has been supported by the ANR project PERISTOCH, ANR?19?CE40?0023. CB has been supported by the Institute for Advanced Study at the Technical University of Munich, Germany through a Hans Fischer fellowship and the Engineering and Physical Sciences Research Council (EPSRC), UK through the grant EP/T013613/1. ME has been supported by Germany's Excellence Strategy ? The Berlin Mathematics Research Center MATH+ (EXC-2046/1, project ID: 390685689). AI acknowledges support by an FWF Hertha Firnberg Research Fellowship (T 1199-N). CS has received funding from the European Union's Horizon 2020 research and innovation program under the Marie Sk?odowska?Curie grant agreement No. 754462. Support by INdAM-GNFM is gratefully acknowledged by CS. TH gratefully acknowledges support through SNF grant 200021?175728/1. We also thank two anonymous referees, whose comments and suggestions have helped to improve the presentation of this work.
Funding Information:
CK has been supported by a Lichtenberg Professorship of the VolkswagenStiftung. CK also acknowledges inspiring discussions with Grigorios A. Pavliotis regarding limit problems in differential equations, which were made possible by a TUM John von Neumann Visiting Professorship. NB has been supported by the ANR project PERISTOCH , ANR–19–CE40–0023 . CB has been supported by the Institute for Advanced Study at the Technical University of Munich, Germany through a Hans Fischer fellowship and the Engineering and Physical Sciences Research Council (EPSRC), UK through the grant EP/T013613/1 . ME has been supported by Germany’s Excellence Strategy – The Berlin Mathematics Research Center MATH+ (EXC-2046/1, project ID: 390685689 ). AI acknowledges support by an FWF Hertha Firnberg Research Fellowship ( T 1199-N ). CS has received funding from the European Union’s Horizon 2020 research and innovation program under the Marie Skłodowska–Curie grant agreement No. 754462 . Support by INdAM-GNFM is gratefully acknowledged by CS. TH gratefully acknowledges support through SNF grant . We also thank two anonymous referees, whose comments and suggestions have helped to improve the presentation of this work.
Publisher Copyright:
© 2021 Elsevier B.V.
Funding
CK has been supported by a Lichtenberg Professorship of the VolkswagenStiftung. CK also acknowledges inspiring discussions with Grigorios A. Pavliotis regarding limit problems in differential equations, which were made possible by a TUM John von Neumann Visiting Professorship. NB has been supported by the ANR project PERISTOCH, ANR?19?CE40?0023. CB has been supported by the Institute for Advanced Study at the Technical University of Munich, Germany through a Hans Fischer fellowship and the Engineering and Physical Sciences Research Council (EPSRC), UK through the grant EP/T013613/1. ME has been supported by Germany's Excellence Strategy ? The Berlin Mathematics Research Center MATH+ (EXC-2046/1, project ID: 390685689). AI acknowledges support by an FWF Hertha Firnberg Research Fellowship (T 1199-N). CS has received funding from the European Union's Horizon 2020 research and innovation program under the Marie Sk?odowska?Curie grant agreement No. 754462. Support by INdAM-GNFM is gratefully acknowledged by CS. TH gratefully acknowledges support through SNF grant 200021?175728/1. We also thank two anonymous referees, whose comments and suggestions have helped to improve the presentation of this work. CK has been supported by a Lichtenberg Professorship of the VolkswagenStiftung. CK also acknowledges inspiring discussions with Grigorios A. Pavliotis regarding limit problems in differential equations, which were made possible by a TUM John von Neumann Visiting Professorship. NB has been supported by the ANR project PERISTOCH , ANR–19–CE40–0023 . CB has been supported by the Institute for Advanced Study at the Technical University of Munich, Germany through a Hans Fischer fellowship and the Engineering and Physical Sciences Research Council (EPSRC), UK through the grant EP/T013613/1 . ME has been supported by Germany’s Excellence Strategy – The Berlin Mathematics Research Center MATH+ (EXC-2046/1, project ID: 390685689 ). AI acknowledges support by an FWF Hertha Firnberg Research Fellowship ( T 1199-N ). CS has received funding from the European Union’s Horizon 2020 research and innovation program under the Marie Skłodowska–Curie grant agreement No. 754462 . Support by INdAM-GNFM is gratefully acknowledged by CS. TH gratefully acknowledges support through SNF grant . We also thank two anonymous referees, whose comments and suggestions have helped to improve the presentation of this work.
Funders | Funder number |
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INdAM-GNFM | |
Horizon 2020 Framework Programme | |
Engineering and Physical Sciences Research Council | EP/T013613/1, EXC-2046/1, 390685689 |
Volkswagen Foundation | |
Agence Nationale de la Recherche | |
Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung | 200021−175728/1 |
Austrian Science Fund | T 1199-N |
Horizon 2020 | 754462 |
Institute for Advanced Study, Technische Universität München |
Keywords
- Double limits
- Multiscale dynamics
- Singular perturbation
- Stochastic dynamics