TY - JOUR ID - 30861 TI - On Approximate Birkhoff-James Orthogonality and Approximate $\ast$-orthogonality in $C^\ast$-algebras JO - Sahand Communications in Mathematical Analysis JA - SCMA LA - en SN - 2322-5807 AU - Nabavi Sales, Seyed Mohammad Sadegh AD - Department of Mathematics, Hakim Sabzevari University, P.O. Box 397, Sabzevar, Iran. Y1 - 2019 PY - 2019 VL - 13 IS - 1 SP - 153 EP - 163 KW - Approximate orthogonality KW - Birkhoff--James orthogonality KW - Range-kernel orthogonality KW - $C^\ast$-algebra KW - $\ast$-orthogonality DO - 10.22130/scma.2018.62262.233 N2 - We offer a new definition of $\varepsilon$-orthogonality in normed spaces, and we try to explain some properties of which. Also we introduce some types of $\varepsilon$-orthogonality in an arbitrary  $C^\ast$-algebra $\mathcal{A}$, as a Hilbert $C^\ast$-module over itself, and investigate some of its properties in such spaces. We state some results relating range-kernel orthogonality in $C^*$-algebras. UR - https://scma.maragheh.ac.ir/article_30861.html L1 - https://scma.maragheh.ac.ir/article_30861_f0543a2f5639a20e512cc2c244fb4bd2.pdf ER -