English

Improvements of Berezin number inequalities

Functional Analysis 2018-05-22 v2

Abstract

In this paper, we generalize several Berezin number inequalities involving product of operators. For instance, we show that if A,BA, B are positive operators and XX is any operator, then \begin{align*} \textbf{ber}^{r}(H_{\alpha}(A,B))&\leq\frac{\|X\|^{r}}{2}\textbf{ber}(A^{r}+B^{r})&\leq\frac{\|X\|^{r}}{2}\textbf{ber}(\alpha A^{r}+(1-\alpha)B^{r})+\textbf{ber}((1-\alpha)A^{r}+\alpha B^{r}), \end{align*} where Hα(A,B)=AαXB1α+A1αXBα2H_{\alpha}(A,B)=\frac{A^\alpha XB^{1-\alpha}+A^{1-\alpha} XB^{\alpha}}{2}, 0α10\leq\alpha\leq1 and r2r\geq2.

Keywords

Cite

@article{arxiv.1805.03231,
  title  = {Improvements of Berezin number inequalities},
  author = {Monire Hajmohamadi and Rahmatollah Lashkaripour and Mojtaba Bakherad},
  journal= {arXiv preprint arXiv:1805.03231},
  year   = {2018}
}