Two-parameters pseudo-bosons
arXiv:1010.0204 · doi:10.1007/s10773-010-0525-9
Abstract
We construct a two-parameters example of {\em pseudo-bosons}, and we show that they are not regular, in the sense previously introduced by the author. In particular, we show that two biorthogonal bases of $\Lc^2(\Bbb R)$ can be constructed, which are not Riesz bases, in general.
In press in International Journal of Theoretical Physics