3 papers
math-ph2020
Quantifier elimination theory and maps which preserve semipositivity
Grzegorz Pastuszak, Adam Skowyrski, Andrzej Jamiołkowski
We give an algorithm determining whether a hermiticity-preserving superoperator is positive. In our approach we apply techniques of quantifier elimination theory for real numbers.…
math-ph2020
On maps which preserve semipositivity and quantifier elimination theory for real numbers
Grzegorz Pastuszak, Adam Skowyrski, Andrzej Jamiołkowski
Assume that is a superoperator which preserves hermiticity. We give an algorithm determining whether preserv…
quant-ph2004
On a Stroboscopic Approach to Quantum Tomography of Qudits Governed by Gaussian Semigroups
Andrzej Jamiołkowski
In this paper, we discuss the minimal number of observables, where expectation values at some time instant determine the trajectory of a d-level quantum system ("qudit") governed b…