dorsal/arxiv
View SchemaTime reversal and exchange symmetries of unitary gate capacities
| Authors | Aram W. Harrow, Peter W. Shor |
|---|---|
| Categories | |
| ArXiv ID | quant-ph/0511219 |
| URL | https://arxiv.org/abs/quant-ph/0511219 |
| Journal | IEEE Trans. Inf. Th., vol. 56, no. 1, pp. 462-475, 2010 |
| License | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ |
Abstract
Unitary gates are an interesting resource for quantum communication in part because they are always invertible and are intrinsically bidirectional. This paper explores these two symmetries: time-reversal and exchange of Alice and Bob. We will present examples of unitary gates that exhibit dramatic separations between forward and backward capacities (even when the back communication is assisted by free entanglement) and between entanglement-assisted and unassisted capacities, among many others. Along the way, we will give a general time-reversal rule for relating the capacities of a unitary gate and its inverse that will explain why previous attempts at finding asymmetric capacities failed. Finally, we will see how the ability to erase quantum information and destroy entanglement can be a valuable resource for quantum communication.
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"abstract": "Unitary gates are an interesting resource for quantum communication in part\nbecause they are always invertible and are intrinsically bidirectional. This\npaper explores these two symmetries: time-reversal and exchange of Alice and\nBob. We will present examples of unitary gates that exhibit dramatic\nseparations between forward and backward capacities (even when the back\ncommunication is assisted by free entanglement) and between\nentanglement-assisted and unassisted capacities, among many others. Along the\nway, we will give a general time-reversal rule for relating the capacities of a\nunitary gate and its inverse that will explain why previous attempts at finding\nasymmetric capacities failed. Finally, we will see how the ability to erase\nquantum information and destroy entanglement can be a valuable resource for\nquantum communication.",
"arxiv_id": "quant-ph/0511219",
"authors": [
"Aram W. Harrow",
"Peter W. Shor"
],
"categories": [
"quant-ph"
],
"journal_ref": "IEEE Trans. Inf. Th., vol. 56, no. 1, pp. 462-475, 2010",
"license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
"title": "Time reversal and exchange symmetries of unitary gate capacities",
"url": "https://arxiv.org/abs/quant-ph/0511219"
},
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