{"title":"A computable ordinary differential equation which possesses no computable solution","authors":"Marian Boylan Pour-el, Ian Richards","doi":"10.1016/0003-4843(79)90021-4","DOIUrl":null,"url":null,"abstract":"<div><p>We prove that there exists a computable—and hence continuous,-function <em>F</em>(v,x) defined α a rectangle <em>R</em> of the plane such that the differential equation <em>x</em>′=<em>F</em><sub><em>x</em>,<em>v</em></sub> has no computable solution of any neighborhood within <em>R</em>. As an immediate corollary, we obtain from the form of the above differential equation a computable transformation with no computable fixed point.</p></div>","PeriodicalId":100093,"journal":{"name":"Annals of Mathematical Logic","volume":"17 1","pages":"Pages 61-90"},"PeriodicalIF":0.0000,"publicationDate":"1979-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0003-4843(79)90021-4","citationCount":"162","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Annals of Mathematical Logic","FirstCategoryId":"1085","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/0003484379900214","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 162
Abstract
We prove that there exists a computable—and hence continuous,-function F(v,x) defined α a rectangle R of the plane such that the differential equation x′=Fx,v has no computable solution of any neighborhood within R. As an immediate corollary, we obtain from the form of the above differential equation a computable transformation with no computable fixed point.