Using the fluctuation-dissipation theorem for nonconservative forces
An equilibrium system which is perturbed by an external potential relaxes to a new equilibrium state, a process obeying the fluctuation-dissipation theorem. In contrast, perturbing by nonconservative forces yields a nonequilibrium steady state, and the fluctuation-dissipation theorem can in general...
| Main Authors: | , |
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| Format: | Article |
| Language: | English |
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American Physical Society
2019-12-01
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| Series: | Physical Review Research |
| Online Access: | http://doi.org/10.1103/PhysRevResearch.1.033151 |
| _version_ | 1797211583061950464 |
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| author | Kiryl Asheichyk Matthias Krüger |
| author_facet | Kiryl Asheichyk Matthias Krüger |
| author_sort | Kiryl Asheichyk |
| collection | DOAJ |
| description | An equilibrium system which is perturbed by an external potential relaxes to a new equilibrium state, a process obeying the fluctuation-dissipation theorem. In contrast, perturbing by nonconservative forces yields a nonequilibrium steady state, and the fluctuation-dissipation theorem can in general not be applied. Here we exploit a freedom inherent to linear response theory: Force fields which perform work that does not couple statistically to the considered observable can be added without changing the response. Using this freedom, we demonstrate that the fluctuation-dissipation theorem can be applied for certain nonconservative forces. We discuss the case of a nonconservative force field linear in particle coordinates, where the mentioned freedom can be formulated in terms of symmetries. In particular, for the case of shear, this yields a response formula, which we find advantageous over the known Green-Kubo relation in terms of statistical accuracy. |
| first_indexed | 2024-04-24T10:28:47Z |
| format | Article |
| id | doaj.art-175201cd326a45c79d9bc54cf507b4ec |
| institution | Directory Open Access Journal |
| issn | 2643-1564 |
| language | English |
| last_indexed | 2024-04-24T10:28:47Z |
| publishDate | 2019-12-01 |
| publisher | American Physical Society |
| record_format | Article |
| series | Physical Review Research |
| spelling | doaj.art-175201cd326a45c79d9bc54cf507b4ec2024-04-12T16:47:26ZengAmerican Physical SocietyPhysical Review Research2643-15642019-12-011303315110.1103/PhysRevResearch.1.033151Using the fluctuation-dissipation theorem for nonconservative forcesKiryl AsheichykMatthias KrügerAn equilibrium system which is perturbed by an external potential relaxes to a new equilibrium state, a process obeying the fluctuation-dissipation theorem. In contrast, perturbing by nonconservative forces yields a nonequilibrium steady state, and the fluctuation-dissipation theorem can in general not be applied. Here we exploit a freedom inherent to linear response theory: Force fields which perform work that does not couple statistically to the considered observable can be added without changing the response. Using this freedom, we demonstrate that the fluctuation-dissipation theorem can be applied for certain nonconservative forces. We discuss the case of a nonconservative force field linear in particle coordinates, where the mentioned freedom can be formulated in terms of symmetries. In particular, for the case of shear, this yields a response formula, which we find advantageous over the known Green-Kubo relation in terms of statistical accuracy.http://doi.org/10.1103/PhysRevResearch.1.033151 |
| spellingShingle | Kiryl Asheichyk Matthias Krüger Using the fluctuation-dissipation theorem for nonconservative forces Physical Review Research |
| title | Using the fluctuation-dissipation theorem for nonconservative forces |
| title_full | Using the fluctuation-dissipation theorem for nonconservative forces |
| title_fullStr | Using the fluctuation-dissipation theorem for nonconservative forces |
| title_full_unstemmed | Using the fluctuation-dissipation theorem for nonconservative forces |
| title_short | Using the fluctuation-dissipation theorem for nonconservative forces |
| title_sort | using the fluctuation dissipation theorem for nonconservative forces |
| url | http://doi.org/10.1103/PhysRevResearch.1.033151 |
| work_keys_str_mv | AT kirylasheichyk usingthefluctuationdissipationtheoremfornonconservativeforces AT matthiaskruger usingthefluctuationdissipationtheoremfornonconservativeforces |