dorsal/arxiv
View SchemaStochastic simulations of conditional states of partially observed systems, quantum and classical
| Authors | Jay Gambetta, H. M. Wiseman |
|---|---|
| Categories | |
| ArXiv ID | quant-ph/0503241 |
| URL | https://arxiv.org/abs/quant-ph/0503241 |
| DOI | 10.1088/1464-4266/7/10/008 |
| Journal | Journal of Optics B: Quantum and Semiclassical Optics 7, S250 (2005) |
Abstract
In a partially observed quantum or classical system the information that we cannot access results in our description of the system becoming mixed even if we have perfect initial knowledge. That is, if the system is quantum the conditional state will be given by a state matrix $\rho_r(t)$ and if classical the conditional state will be given by a probability distribution $P_r(x,t)$ where $r$ is the result of the measurement. Thus to determine the evolution of this conditional state under continuous-in-time monitoring requires an expensive numerical calculation. In this paper we demonstrating a numerical technique based on linear measurement theory that allows us to determine the conditional state using only pure states. That is, our technique reduces the problem size by a factor of $N$, the number of basis states for the system. Furthermore we show that our method can be applied to joint classical and quantum systems as arises in modeling realistic measurement.
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"abstract": "In a partially observed quantum or classical system the information that we\ncannot access results in our description of the system becoming mixed even if\nwe have perfect initial knowledge. That is, if the system is quantum the\nconditional state will be given by a state matrix $\\rho_r(t)$ and if classical\nthe conditional state will be given by a probability distribution $P_r(x,t)$\nwhere $r$ is the result of the measurement. Thus to determine the evolution of\nthis conditional state under continuous-in-time monitoring requires an\nexpensive numerical calculation. In this paper we demonstrating a numerical\ntechnique based on linear measurement theory that allows us to determine the\nconditional state using only pure states. That is, our technique reduces the\nproblem size by a factor of $N$, the number of basis states for the system.\nFurthermore we show that our method can be applied to joint classical and\nquantum systems as arises in modeling realistic measurement.",
"arxiv_id": "quant-ph/0503241",
"authors": [
"Jay Gambetta",
"H. M. Wiseman"
],
"categories": [
"quant-ph"
],
"doi": "10.1088/1464-4266/7/10/008",
"journal_ref": "Journal of Optics B: Quantum and Semiclassical Optics 7, S250\n (2005)",
"title": "Stochastic simulations of conditional states of partially observed systems, quantum and classical",
"url": "https://arxiv.org/abs/quant-ph/0503241"
},
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