Journals / İstanbul University Science Faculty The Journal Of Mathematics Physics and Astronomy / 2014 / Cilt: 5
A Version of Lagrange's Theorem for Some Classes of Functions of Many Variables
- Issue
- 2014 · Cilt: 5
- Pages
- 1–8
- DOI
- —
Abstract
The famous mean motion problem which goes back to Lagrange asfollows: to prove that any exponential polynomial with exponentson the imaginary axis has an average speed for the amplitude,whenever the variable moves along a horizontal line. It wascompletely proved by B.\,Jessen and H.\,Tornehave in Acta Math.77,1945. Actually, this result is a consequence of almost periodicityin Weyl's sense of amplitude increments over segments of thelength 1. Here we consider the problem for some classes of almostperiodic functions of several variables.