The truncated univariate rational moment problem

Nailwal, Rajkamal (avtor), Zalar, Aljaž (avtor)

Given a closed subset $K$ in ${\mathbb R}$, the rational $K$-truncated moment problem ($K$-RTMP) asks to characterize the existence of a positive Borel measure $\mu$, supported on $K$, such that a linear functional ${\mathcal L}$, defined on all rational functions of the form ${f \over q}$, where $q$ is a fixed polynomial with all real zeros of even order and $f$ is any real polynomial of degree at most $2k$, is an integration with respect to $\mu$. The case of a compact set $K$ was solved by Chandler in 1994, but there is no argument that ensures that $\mu$ vanishes on all real zeros of $q$. An obvious necessary condition for the solvability of the $K$-RTMP is that ${\mathcal L}$ is nonnegative on every $f$ satisfying $f|_K \ge 0$. If ${\mathcal L}$ is strictly positive on every $0 \ne f|_K \ge 0$, we add the missing argument in Chadler's solution and also bound the number of atoms in a minimal representing measure. We show by an example that nonnegativity of ${\mathcal L}$ is not sufficient and add the missing conditions to the solution. We also solve the $K$-RTMP for unbounded $K$ and derive the solutions to the strong truncated Hamburger moment problem and the truncated moment problem on the unit circle as special cases.

• Jezik: Angleški jezik
• Ključne besede: truncated moment problem, rational truncated moment problem, representing measure, moment matrix, localizing moment matrix, preordering
• Vrsta gradiva: Članek v reviji
• Tipologija: 1.01 - Izvirni znanstveni članek
• Organizacija: FRI - Fakulteta za računalništvo in informatiko; FMF - Fakulteta za matematiko in fiziko
• Status publikacije: Objavljeno
• Različica publikacije: Objavljena publikacija
• Leto izida: 2025
• Št. strani: Str. 280-301
• Številčenje: Vol. 708
• PID: 20.500.12556/RUL-166351
• UDK: 517.9
• ISSN pri članku: 0024-3795
• DOI: 10.1016/j.laa.2024.12.009
• COBISS.SI-ID: 219899139
• Datum objave v RUL: 08.01.2025

Gradivo je del revije

• Naslov: Linear algebra and its applications
• Skrajšan naslov: Linear algebra appl.
• Založnik: Elsevier
• ISSN: 0024-3795
• COBISS.SI-ID: 1119247

Licence

• Licenca: CC BY 4.0, Creative Commons Priznanje avtorstva 4.0 Mednarodna
• Povezava: http://creativecommons.org/licenses/by/4.0/deed.sl
• Opis: To je standardna licenca Creative Commons, ki daje uporabnikom največ možnosti za nadaljnjo uporabo dela, pri čemer morajo navesti avtorja.

Sekundarni jezik

• Jezik: Slovenski jezik
• Ključne besede: prirezani momentni problem, racionalni prirezani momentni problem, reprezentirajoča mera, momentna matrika, lokalizirajoča momentna matrika, predureditev