dorsal/arxiv
View SchemaA Note on (Spin-) Coherent-State Path Integral
| Authors | Junya Shibata, Shin Takagi |
|---|---|
| Categories | |
| ArXiv ID | quant-ph/9807005 |
| URL | https://arxiv.org/abs/quant-ph/9807005 |
| DOI | 10.1142/S0217979299000096 |
| Journal | Int.J.Mod.Phys. B13 (1999) 107-140 |
Abstract
It is pointed out that there are some fundamental difficulties with the frequently used continuous-time formalism of the spin-coherent-state path integral. They arise already in a single-spin system and at the level of the "classical action" not to speak of fluctuations around the "classical path". Similar difficulties turn out to be present in the case of the (boson-)coherent-state path integral as well; although partially circumventable by an ingenious trick (Klauder's $\epsilon$-prescription) at the "classical level", they manifest themselves at the level of fluctuations. Detailed analysis of the origin of these difficulties makes it clear that the only way of avoiding them is to work with the proper discrete-time formalism. The thesis is explicitly illustrated with a harmonic oscillator and a spin under a constant magnetic field.
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"abstract": "It is pointed out that there are some fundamental difficulties with the\nfrequently used continuous-time formalism of the spin-coherent-state path\nintegral. They arise already in a single-spin system and at the level of the\n\"classical action\" not to speak of fluctuations around the \"classical path\".\nSimilar difficulties turn out to be present in the case of the\n(boson-)coherent-state path integral as well; although partially circumventable\nby an ingenious trick (Klauder\u0027s $\\epsilon$-prescription) at the \"classical\nlevel\", they manifest themselves at the level of fluctuations. Detailed\nanalysis of the origin of these difficulties makes it clear that the only way\nof avoiding them is to work with the proper discrete-time formalism. The thesis\nis explicitly illustrated with a harmonic oscillator and a spin under a\nconstant magnetic field.",
"arxiv_id": "quant-ph/9807005",
"authors": [
"Junya Shibata",
"Shin Takagi"
],
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"quant-ph"
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"doi": "10.1142/S0217979299000096",
"journal_ref": "Int.J.Mod.Phys. B13 (1999) 107-140",
"title": "A Note on (Spin-) Coherent-State Path Integral",
"url": "https://arxiv.org/abs/quant-ph/9807005"
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