Are problems in Quantum Information Theory (un)decidable?

This note is intended to foster a discussion about the extent to which typical problems arising in quantum information theory are algorithmically decidable (in principle rather than in practice). Various problems in the context of entanglement theory and quantum channels turn out to be decidable via...

Descripción completa

Detalles Bibliográficos
Autores: Wolf, Michael M., Cubitt, Toby S., Pérez García, David
Tipo de recurso: artículo
Fecha de publicación:2011
País:España
Institución:Universidad Complutense de Madrid (UCM)
Repositorio:Docta Complutense
Idioma:inglés
OAI Identifier:oai:docta.ucm.es:20.500.14352/44449
Acceso en línea:https://hdl.handle.net/20.500.14352/44449
Access Level:acceso abierto
Palabra clave:51-73
530.145
Física matemática
Teoría de los quanta
2210.23 Teoría Cuántica
Descripción
Sumario:This note is intended to foster a discussion about the extent to which typical problems arising in quantum information theory are algorithmically decidable (in principle rather than in practice). Various problems in the context of entanglement theory and quantum channels turn out to be decidable via quantifier elimination as long as they admit a compact formulation without quantification over integers. For many asymptotically defined properties which have to hold for all or for one n € N, however, effective procedures seem to be difficult if not impossible to find. We review some of the main tools for (dis)proving decidability and apply them to problems in quantum information theory. We find that questions like ”can we overcome fidelity 1/2 w.r.t. a two-qubit singlet state?” easily become undecidable. A closer look at such questions might rule out some of the “single-letter” formulas sought in quantum information theory.