Pseudo $S$-spectra of special operators in quaternionic Hilbert spaces

Kousik Dhara, Santhosh Kumar Pamula

For a bounded quaternionic operator $T$ on a right quaternionic Hilbert space $\mathcal{H}$ and $\epsilon >0$, the pseudo $S$-spectrum of $T$ is defined as \begin{align*} Λ_{\va…