dorsal/arxiv
View SchemaOne qubit almost completely reveals the dynamics of two
| Authors | Thomas F. Jordan, Anil Shaji, E. C. G. Sudarshan |
|---|---|
| Categories | |
| ArXiv ID | quant-ph/0611141 |
| URL | https://arxiv.org/abs/quant-ph/0611141 |
| DOI | 10.1103/PhysRevA.76.012101 |
Abstract
From the time dependence of states of one of them, the dynamics of two interacting qubits is determined to be one of two possibilities that differ only by a change of signs of parameters in the Hamiltonian. The only exception is a simple particular case where several parameters in the Hamiltonian are zero and one of the remaining nonzero parameters has no effect on the time dependence of states of the one qubit. The mean values that describe the initial state of the other qubit and of the correlations between the two qubits also are generally determined to within a change of signs by the time dependence of states of the one qubit, but with many more exceptions. An example demonstrates all the results. Feedback in the equations of motion that allows time dependence in a subsystem to determine the dynamics of the larger system can occur in both classical and quantum mechanics. The role of quantum mechanics here is just to identify qubits as the simplest objects to consider and specify the form that equations of motion for two interacting qubits can take.
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"abstract": "From the time dependence of states of one of them, the dynamics of two\ninteracting qubits is determined to be one of two possibilities that differ\nonly by a change of signs of parameters in the Hamiltonian. The only exception\nis a simple particular case where several parameters in the Hamiltonian are\nzero and one of the remaining nonzero parameters has no effect on the time\ndependence of states of the one qubit. The mean values that describe the\ninitial state of the other qubit and of the correlations between the two qubits\nalso are generally determined to within a change of signs by the time\ndependence of states of the one qubit, but with many more exceptions. An\nexample demonstrates all the results. Feedback in the equations of motion that\nallows time dependence in a subsystem to determine the dynamics of the larger\nsystem can occur in both classical and quantum mechanics. The role of quantum\nmechanics here is just to identify qubits as the simplest objects to consider\nand specify the form that equations of motion for two interacting qubits can\ntake.",
"arxiv_id": "quant-ph/0611141",
"authors": [
"Thomas F. Jordan",
"Anil Shaji",
"E. C. G. Sudarshan"
],
"categories": [
"quant-ph"
],
"doi": "10.1103/PhysRevA.76.012101",
"title": "One qubit almost completely reveals the dynamics of two",
"url": "https://arxiv.org/abs/quant-ph/0611141"
},
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