Entanglement of four qubit systems: A geometric atlas with polynomial compass I (the finite world)
- Laboratoire IRTES-M3M, Université de Technologie de Belfort-Montbéliard, 90010 Belfort Cedex (France)
- Université de Rouen, Laboratoire d'Informatique, du Traitement de l'Information et des Systèmes (LITIS), Avenue de l'Université – BP 8, 6801 Saint-étienne-du-Rouvray Cedex (France)
- Labroatoire d'Informatique Gaspard Monge Université Paris-Est Marne-la-Vallée, 77454 Marne-la-Vallée Cedex 2 (France)
We investigate the geometry of the four qubit systems by means of algebraic geometry and invariant theory, which allows us to interpret certain entangled states as algebraic varieties. More precisely we describe the nullcone, i.e., the set of states annihilated by all invariant polynomials, and also the so-called third secant variety, which can be interpreted as the generalization of GHZ-states for more than three qubits. All our geometric descriptions go along with algorithms which allow us to identify any given state in the nullcone or in the third secant variety as a point of one of the 47 varieties described in the paper. These 47 varieties correspond to 47 non-equivalent entanglement patterns, which reduce to 15 different classes if we allow permutations of the qubits.
- OSTI ID:
- 22251202
- Journal Information:
- Journal of Mathematical Physics, Vol. 55, Issue 1; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0022-2488
- Country of Publication:
- United States
- Language:
- English
Similar Records
Polynomial invariants for discrimination and classification of four-qubit entanglement
Constraints on SU(2) Circled-Times SU(2) invariant polynomials for a pair of entangled qubits