Title Cosine polynomials with few zeros /
Authors Juőkevičius, Tomas ; Sahasrabudhe, Julian
DOI 10.1112/blms.12468
Full Text Download
Is Part of Bulletin of the London Mathematical Society.. Hoboken : Wiley. 2021, vol. 53, iss. 3, p. 877-892.. ISSN 0024-6093. eISSN 1469-2120
Keywords [eng] cosine polynomials ; old conjecture of Littlewood ; analysis of their constructions
Abstract [eng] In a celebrated paper, Borwein, ErdΓ©lyi, Ferguson and Lockhart constructed cosine polynomials of the form 𝑓𝐴(π‘₯)=βˆ‘π‘Žβˆˆπ΄cos(π‘Žπ‘₯), with π΄βŠ†β„•, |𝐴|=𝑛 and as few as 𝑛5/6+π‘œ(1) zeros in [0,2πœ‹], thereby disproving an old conjecture of Littlewood. Here we give a sharp analysis of their constructions and, as a result, prove that there exist examples with as few as 𝐢(𝑛log𝑛)2/3 zeros.
Published Hoboken : Wiley
Type Journal article
Language English
Publication date 2021
CC license CC license description