TY - JOUR T1 - Invariance of Conjugate Normality Under Similarity AU - Wang , Cun AU - Yu , Meng AU - Liang , Minyi JO - Communications in Mathematical Research VL - 3 SP - 245 EP - 260 PY - 2024 DA - 2024/09 SN - 40 DO - http://doi.org/10.4208/cmr.2024-0002 UR - https://global-sci.org/intro/article_detail/cmr/23411.html KW - $C$-normal operators, complex symmetric operators, similarity. AB -

An operator $T$ on a separable, infinite dimensional, complex Hilbert space $\mathcal{H}$ is called conjugate normal if $C|T|C = |T^∗|$ for some conjugate linear, isometric involution $C$ on $\mathcal{H}.$ This paper focuses on the invariance of conjugate normality under similarity. Given an operator $T,$ we prove that every operator $A$ similar to $T$ is conjugate normal if and only if there exist complex numbers $λ_1$, $λ_2$ such that $(T−λ_1)(T−λ_2)=0.$