Negativity of the Casimir Self-Entropy in Spherical Geometries
It has been recognized for some time that, even for perfect conductors, the interaction Casimir entropy, due to quantum/thermal fluctuations, can be negative. This result was not considered problematic because it was thought that the self-entropies of the bodies would cancel this negative interactio...
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| Format: | Article |
| Language: | English |
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MDPI AG
2021-02-01
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| Series: | Entropy |
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| Online Access: | https://www.mdpi.com/1099-4300/23/2/214 |
| _version_ | 1797411909285183488 |
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| author | Yang Li Kimball A. Milton Prachi Parashar Lujun Hong |
| author_facet | Yang Li Kimball A. Milton Prachi Parashar Lujun Hong |
| author_sort | Yang Li |
| collection | DOAJ |
| description | It has been recognized for some time that, even for perfect conductors, the interaction Casimir entropy, due to quantum/thermal fluctuations, can be negative. This result was not considered problematic because it was thought that the self-entropies of the bodies would cancel this negative interaction entropy, yielding a total entropy that was positive. In fact, this cancellation seems not to occur. The positive self-entropy of a perfectly conducting sphere does indeed just cancel the negative interaction entropy of a system consisting of a perfectly conducting sphere and plate, but a model with weaker coupling in general possesses a regime where negative self-entropy appears. The physical meaning of this surprising result remains obscure. In this paper, we re-examine these issues, using improved physical and mathematical techniques, partly based on the Abel–Plana formula, and present numerical results for arbitrary temperatures and couplings, which exhibit the same remarkable features. |
| first_indexed | 2024-03-09T04:53:10Z |
| format | Article |
| id | doaj.art-898dddbc75194dbc9a4dd0ec731491f8 |
| institution | Directory Open Access Journal |
| issn | 1099-4300 |
| language | English |
| last_indexed | 2024-03-09T04:53:10Z |
| publishDate | 2021-02-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Entropy |
| spelling | doaj.art-898dddbc75194dbc9a4dd0ec731491f82023-12-03T13:08:31ZengMDPI AGEntropy1099-43002021-02-0123221410.3390/e23020214Negativity of the Casimir Self-Entropy in Spherical GeometriesYang Li0Kimball A. Milton1Prachi Parashar2Lujun Hong3Department of Physics, Nanchang University, Nanchang 330031, ChinaHomer L. Dodge Department of Physics and Astronomy, University of Oklahoma, Norman, OK 73019, USAJohn A. Logan College, Carterville, IL 62918, USAInstitute of Space Science and Technology, Nanchang University, Nanchang 330031, ChinaIt has been recognized for some time that, even for perfect conductors, the interaction Casimir entropy, due to quantum/thermal fluctuations, can be negative. This result was not considered problematic because it was thought that the self-entropies of the bodies would cancel this negative interaction entropy, yielding a total entropy that was positive. In fact, this cancellation seems not to occur. The positive self-entropy of a perfectly conducting sphere does indeed just cancel the negative interaction entropy of a system consisting of a perfectly conducting sphere and plate, but a model with weaker coupling in general possesses a regime where negative self-entropy appears. The physical meaning of this surprising result remains obscure. In this paper, we re-examine these issues, using improved physical and mathematical techniques, partly based on the Abel–Plana formula, and present numerical results for arbitrary temperatures and couplings, which exhibit the same remarkable features.https://www.mdpi.com/1099-4300/23/2/214Casimir free energyentropyAbel–Plana formula |
| spellingShingle | Yang Li Kimball A. Milton Prachi Parashar Lujun Hong Negativity of the Casimir Self-Entropy in Spherical Geometries Entropy Casimir free energy entropy Abel–Plana formula |
| title | Negativity of the Casimir Self-Entropy in Spherical Geometries |
| title_full | Negativity of the Casimir Self-Entropy in Spherical Geometries |
| title_fullStr | Negativity of the Casimir Self-Entropy in Spherical Geometries |
| title_full_unstemmed | Negativity of the Casimir Self-Entropy in Spherical Geometries |
| title_short | Negativity of the Casimir Self-Entropy in Spherical Geometries |
| title_sort | negativity of the casimir self entropy in spherical geometries |
| topic | Casimir free energy entropy Abel–Plana formula |
| url | https://www.mdpi.com/1099-4300/23/2/214 |
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