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<ArticleSet>
<Article>
<Journal>
<PublisherName>OICC Press</PublisherName>
<JournalTitle>Mathematical Analysis and its Contemporary Applications</JournalTitle>
<Issn></Issn>
<Volume>7</Volume>
<Issue>2</Issue>
<PubDate PubStatus="epublish">
<Year>2025</Year>
<Month>05</Month>
<Day>26</Day>
</PubDate>
</Journal>
<ArticleTitle>Orthogonality of algebraic elementary operators when their numerical ranges are spheroidal</ArticleTitle>
<VernacularTitle></VernacularTitle>
<FirstPage></FirstPage>
<LastPage></LastPage>
<ELocationID EIdType="doi">10.30495/maca.2025.2055200.1132</ELocationID>
<Language>EN</Language>
<AuthorList>
<Author>
<FirstName>James Mwangi</FirstName>
<LastName>Njoroge</LastName>
<Affiliation>Department of Pure and Applied Mathematics, Jaramogi Oginga Odinga University of Science and Technology, P.O. Box 210-40601, Bondo, Kenya</Affiliation>
<Identifier Source="ORCID"></Identifier>
</Author>
<Author>
<FirstName>Benard</FirstName>
<LastName>Okelo</LastName>
<Affiliation>Department of Pure and Applied Mathematics, Jaramogi Oginga Odinga University of Science and Technology, P.O. Box 210-40601, Bondo, Kenya</Affiliation>
<Identifier Source="ORCID">https://orcid.org/0000-0003-3963-1910</Identifier>
</Author>
<Author>
<FirstName>Priscah</FirstName>
<LastName>Omoke</LastName>
<Affiliation>Department of Pure and Applied Mathematics, Jaramogi Oginga Odinga University of Science and Technology, P.O. Box 210-40601, Bondo, Kenya</Affiliation>
<Identifier Source="ORCID"></Identifier>
</Author>
</AuthorList>
<PublicationType>Journal Article</PublicationType>
<History>
<PubDate PubStatus="received">
<Year>2025</Year>
<Month>05</Month>
<Day>26</Day>
</PubDate>
</History>
<Abstract>Characterizations involving algebraic elementary operators have been done over the years, for instance, orthogonality when the operators are induced by other different types of transformations. In particular, algebraic elementary operators induced by norm-attainable maps have not been characterized in terms of orthogonality when their numerical ranges have spheroid boundaries. In this note, we characterize algebraic elementary operators in terms of Birkhoff-James orthogonality when they are induced by norm-attainable maps and the boundaries of their numerical ranges are spheroidal in shape. We show that under the spheroidicity criterion for the numerical range boundary, various types of algebraic elementary operators satisfy Birkhoff-James orthogonality.</Abstract>
<ObjectList>
<Object Type="keyword">
<Param Name="value">Numerical range</Param>
</Object>
<Object Type="keyword">
<Param Name="value">Elementary operator</Param>
</Object>
<Object Type="keyword">
<Param Name="value">Orthogonal projection</Param>
</Object>
</ObjectList>
</Article>
</ArticleSet>