THERMAL SCIENCE
International Scientific Journal
APPROXIMATION OF BLOCK NUMERICAL RANGE FOR HAMILTONIAN OPERATOR MATRIX
ABSTRACT
The aim of this paper is to derive approximations for the block numerical range of unbounded block operator matrices that are block dominant. To illustrate our approach, we calculate the quartic numerical range of a concrete Hamiltonian operator matrix.
KEYWORDS
PAPER SUBMITTED: 2024-03-23
PAPER REVISED: 2024-06-23
PAPER ACCEPTED: 2024-06-23
PUBLISHED ONLINE: 2025-07-06
THERMAL SCIENCE YEAR
2025, VOLUME
29, ISSUE
Issue 3, PAGES [2085 - 2093]
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