dorsal/arxiv
View SchemaGeneral Classes of Impossible Operations through the Existence of Incomparable States
| Authors | Indrani Chattopadhyay, Debasis Sarkar |
|---|---|
| Categories | |
| ArXiv ID | quant-ph/0609226 |
| URL | https://arxiv.org/abs/quant-ph/0609226 |
| Journal | Quantum Information and Computation, 7 (2007) 392-400 |
Abstract
In this work we show that the most general class of anti-unitary operators are nonphysical in nature through the existence of incomparable pure bipartite entangled states. It is also shown that a large class of inner-product-preserving operations defined only on the three qubits having spin-directions along x, y and z are impossible. If we perform such an operation locally on a particular pure bipartite state then it will exactly transform to another pure bipartite state that is incomparable with the original one. As subcases of the above results we find the nonphysical nature of universal exact flipping operation and existence of universal Hadamard gate. Beyond the information conservation in terms of entanglement, this work shows how an impossible local operation evolve with the joint system in a nonphysical way.
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"abstract": "In this work we show that the most general class of anti-unitary operators\nare nonphysical in nature through the existence of incomparable pure bipartite\nentangled states. It is also shown that a large class of\ninner-product-preserving operations defined only on the three qubits having\nspin-directions along x, y and z are impossible. If we perform such an\noperation locally on a particular pure bipartite state then it will exactly\ntransform to another pure bipartite state that is incomparable with the\noriginal one. As subcases of the above results we find the nonphysical nature\nof universal exact flipping operation and existence of universal Hadamard gate.\nBeyond the information conservation in terms of entanglement, this work shows\nhow an impossible local operation evolve with the joint system in a nonphysical\nway.",
"arxiv_id": "quant-ph/0609226",
"authors": [
"Indrani Chattopadhyay",
"Debasis Sarkar"
],
"categories": [
"quant-ph"
],
"journal_ref": "Quantum Information and Computation, 7 (2007) 392-400",
"title": "General Classes of Impossible Operations through the Existence of Incomparable States",
"url": "https://arxiv.org/abs/quant-ph/0609226"
},
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