Point evaluation in Paley--Wiener spaces

التفاصيل البيبلوغرافية
العنوان: Point evaluation in Paley--Wiener spaces
المؤلفون: Brevig, Ole Fredrik, Chirre, Andrés, Ortega-Cerdà, Joaquim, Seip, Kristian
سنة النشر: 2022
المجموعة: Mathematics
مصطلحات موضوعية: Mathematics - Classical Analysis and ODEs, Mathematics - Complex Variables, Mathematics - Functional Analysis
الوصف: We study the norm of point evaluation at the origin in the Paley--Wiener space $PW^p$ for $0 < p < \infty$, i. e., we search for the smallest positive constant $C$, called $\mathscr{C}_p$, such that the inequality $|f(0)|^p \leq C \|f\|_p^p$ holds for every $f$ in $PW^p$. We present evidence and prove several results supporting the following monotonicity conjecture: The function $p\mapsto \mathscr{C}_p/p$ is strictly decreasing on the half-line $(0,\infty)$. Our main result implies that $\mathscr{C}_p

p/2$ for $1 \leq p < 2$. We also estimate the asymptotic behavior of $\mathscr{C}_p$ as $p \to \infty$ and as $p \to 0^+$. Our approach is based on expressing $\mathscr{C}_p$ as the solution of an extremal problem. Extremal functions exist for all $0Comment: Minor corrections to Theorem 1.4 and Lemma 3.1. This paper has been accepted for publication in Journal d'Analyse Math\'{e}matique

نوع الوثيقة: Working Paper
URL الوصول: http://arxiv.org/abs/2210.13922
رقم الأكسشن: edsarx.2210.13922
قاعدة البيانات: arXiv