On solutions of a nonlinear wave question when the ratio of the period to the length of the interval is irrational
On solutions of a nonlinear wave question when the ratio of the period to the length of the interval is irrational
The semilinear wave equation <inline-formula content-type="math/mathml"> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="u Subscript t t Baseline minus u Subscript x x Baseline plus f left-parenthesis u right-parenthesis equals g left-parenthesis t right-parenthesis"> <mml:semantics> <mml:mrow> <mml:mrow class="MJX-TeXAtom-ORD"> <mml:msub> <mml:mi>u</mml:mi> <mml:mrow class="MJX-TeXAtom-ORD"> <mml:mi>t</mml:mi> <mml:mi>t</mml:mi> </mml:mrow> </mml:msub> </mml:mrow> <mml:mo>−<!-- − --></mml:mo> <mml:mrow class="MJX-TeXAtom-ORD"> <mml:msub> <mml:mi>u</mml:mi> <mml:mrow …