提出了一种计算几何奇异扰动问题中慢流形及其快纤维丛的新方法。这种独立于坐标的方法受到Cabré,Fontich和de la Llave引入的参数化方法的启发。通过迭代求解所谓的共轭方程,我们的方法同时计算参数化的慢流形和快速纤维束,以及这些对象上的动态,以任意高的精度。我们展示了这种自上而下的方法在研究具有多个(即,三个或更多)时间尺度。特别是,我们强调了隐藏的时间尺度的出现,并展示了我们的方法如何发现这些令人惊讶的多个时间尺度结构。我们还将我们的参数化方法应用到几个反应网络问题。
英文摘要:
We present a novel method for computing slow manifolds and their fast fibre bundles in geometric singular perturbation problems. This coordinate-independent method is inspired by the parametrisation method introduced by Cabré, Fontich and de la Llave. By iteratively solving a so-called conjugacy equation, our method simultaneously computes parametrisations of slow manifolds and fast fibre bundles, as well as the dynamics on these objects, to arbitrarily high degrees of accuracy. We show the power of this top-down method for the study of systems with multiple (i.e., three or more) timescales. In particular, we highlight the emergence of hidden timescales and show how our method can uncover these surprising multiple timescale structures. We also apply our parametrisation method to several reaction network problems.
Escape, Oscillatory Relapse or Elimination: A Geometric Blow-up Analysis of a Tumour Model with Singular Bifurcations
Imagination Corp.(想象公司);Department of Applied Mathematics, Fictional University(虚构大学应用数学系);School of Mathematics and Statistics, The University of Sydney(悉尼大学数学与统计学院)
Geometric singular perturbation analysis of the multiple-timescale Hodgkin-Huxley equations
我们提出了一个新的和全球性的三维约化的无量纲版本的四维霍奇金-赫胥黎方程[J。鲁宾和M。Wechselberger,Giant squid--hidden canard:the 3D geometry of the Hodgkin-Huxley model,Biological Cybernetics,97(2007),pp. 5- 32],该方法基于几何奇异扰动理论(GSPT)。我们调查所产生的三维系统中的两个参数制度,在三个不同的时间尺度上的流动演变的动力学。具体地说,我们证明了该系统的振荡动力学和复杂的混合模式振荡(MMO)的分叉,根据几何机制介绍[P. Kaklamanos,N。Popović,and K.联合Kristiansen,Bifurcations of mixed-mode oscillations in three-timescale systems:An extended prototypical example,Chaos:An Interdisciplinary Journal of Nonlinear Science,32(2022),p.013108],我们根据外部施加电流对各种点火模式进行了分类。虽然这种模式已被记录在[S。土井,S. Nabetani和S. Kumagai,时间尺度变化引起的Hodgkin-Huxley方程的复杂非线性动力学,生物…
Singular basins in multiscale systems: tunneling between stable states
University College Cork(科克大学);Potsdam Institute for Climate Impact Research(波茨坦气候影响研究所);Johann Bernoulli Institute for Mathematics and Computer Science, University of Groningen(格罗宁根大学约翰·伯努利数学与计算机科学研究所)