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arXiv · 1708.07438

On the stratifications of 2-qubits X-state space

Arsen Khvedelidze·Astghik Torosyan
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Abstract

The 7-dimensional family $\mathfrak{P}_X$ of so-called mixed X-states of 2-qubits is considered. Two types of stratification of 2-qubits $X-$state space, i.e., partitions of $\mathfrak{P}_X\,$ into orbit types with respect to the adjoint group actions, one of the global unitary group $G_X \subset SU(4)$ and another one under the action of the local unitary group $LG_X \subset G_X$, is described. The equations and inequalities in the invariants of the corresponding groups, determining each stratification component, are given.

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Arsen Khvedelidze, Astghik Torosyan. 2017-08-24. On the stratifications of 2-qubits X-state space. https://doi.org/10.1051/epjconf/201817302011

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