Reuse & Permissions

It is not necessary to obtain permission to reuse this article or its components as it is available under the terms of the Creative Commons Attribution 4.0 International license. This license permits unrestricted use, distribution, and reproduction in any medium, provided attribution to the author(s) and the published article's title, journal citation, and DOI are maintained. Please note that some figures may have been included with permission from other third parties. It is your responsibility to obtain the proper permission from the rights holder directly for these figures.

Export citation

Export citation

Choose format for download:

Download Citation
  • Letter
  • Open Access

Quantum statistical mechanical gauge invariance

Johanna Müller and Matthias Schmidt*

  • *Contact author: Matthias.Schmidt@uni-bayreuth.de

Phys. Rev. E 114, L022104 – Published 14 August, 2026

DOI: https://doi.org/10.1103/dzz3-m28k

Abstract

We address gauge invariance in the statistical mechanics of quantum many-body systems. The gauge transformation acts on the position and momentum degrees of freedom, and it is represented by a quantum shifting superoperator that maps quantum observables onto each other. The shifting superoperator is anti-self-adjoint, and it has noncommutative Lie algebra structure. These properties induce exact equilibrium sum rules that connect locally resolved force and hyperforce densities for any given observable. We argue that the framework is amenable to tight integration into quantum hyperdensity functional theory and that it generalizes naturally to nonequilibrium.

View figure in article

Physics Subject Headings (PhySH)

See Also

Article Text

References (64)

  1. L. O' Raifeartaigh and N. Straumann, Gauge theory: Historical origins and some modern developments, Rev. Mod. Phys. 72, 1 (2000).
  2. J. D. Jackson and L. B. Okun, Historical roots of gauge invariance, Rev. Mod. Phys. 73, 663 (2001).
  3. E. Noether, Invariante Variationsprobleme, Nachr. König. Gesellsch. Wiss. Göttingen, Math.-Phys. Klasse 235, 83 (1918) English translation by M. A. Tavel: Invariant variation problems, Transp. Theo. Stat. Phys. 1, 186 (1971); for a version with corrigenda, Frank Y. Wang, arXiv:physics/0503066.
  4. J. C. Baez and B. Fong, A Noether theorem for Markov processes, J. Math. Phys. 54, 013301 (2013).
  5. I. Marvian and R. W. Spekkens, Extending Noether's theorem by quantifying the asymmetry of quantum states, Nat. Commun. 5, 3821 (2014).
  6. S. I. Sasa and Y. Yokokura, Thermodynamic entropy as a Noether invariant, Phys. Rev. Lett. 116, 140601 (2016).
  7. S. I. Sasa, S. Sugiura, and Y. Yokokura, Thermodynamical path integral and emergent symmetry, Phys. Rev. E 99, 022109 (2019).
  8. A. Bravetti, M. A. Garcia-Ariza, and D. Tapias, Thermodynamic entropy as a Noether invariant from contact geometry, Entropy 25, 1082 (2023).
  9. Y. A. Budkov and A. L. Kolesnikov, Modified Poisson-Boltzmann equations and macroscopic forces in inhomogeneous ionic fluids, J. Stat. Mech. (2022) 053205.
  10. P. E. Brandyshev and Y. A. Budkov, Noether's second theorem and covariant field theory of mechanical stresses in inhomogeneous ionic fluids, J. Chem. Phys. 158, 174114 (2023).
  11. A. Beyen and C. Maes, The first part of Clausius' heat theorem in terms of Noether's theorem, Math. Mech. Compl. Sys. 13, 1 (2025).
  12. J. Müller, S. Hermann, F. Sammüller, and M. Schmidt, Gauge invariance of equilibrium statistical mechanics, Phys. Rev. Lett. 133, 217101 (2024); Editors' Suggestion; Phys. Rev. Lett.'s Collection of the Year 2024; Featured in Physics 17, 163 (2024) by B. Rotenberg.
  13. J. Müller, F. Sammüller, and M. Schmidt, Why gauge invariance applies to statistical mechanics, J. Phys. A: Math. Theor. 58, 125003 (2025).
  14. B. Rotenberg, Viewpoint: Symmetry spotted in statistical mechanics, Physics 17, 163 (2024).
  15. J. L. Miller, Gauge invariance applies to statistical mechanics too, Phys. Today 78(2), 11 (2025).
  16. J. Müller, F. Sammüller, and M. Schmidt, Dynamical gauge invariance of statistical mechanics, arXiv:2504.17599.
  17. S. Hermann and M. Schmidt, Noether's theorem in statistical mechanics, Commun. Phys. 4, 176 (2021).
  18. S. Robitschko, F. Sammüller, M. Schmidt, and S. Hermann, Hyperforce balance from thermal Noether invariance of any observable, Commun. Phys. 7, 103 (2024).
  19. S. Hermann and M. Schmidt, Force balance in thermal quantum many-body systems from Noether's theorem, J. Phys. A: Math. Theor. 55, 464003 (2022).
  20. F. Sammüller, S. Hermann, D. de las Heras, and M. Schmidt, Noether-constrained correlations in equilibrium liquids, Phys. Rev. Lett. 130, 268203 (2023).
  21. J. Yvon, La Théorie Statistique Des Fluides et L'équation D'état, Actualités Scientifiques et Industrielles, (Hermann & Cie., Paris, 1935).
  22. M. Born and H. S. Green, A general kinetic theory of liquids I. The molecular distribution functions, Proc. R. Soc. 188, 10 (1946).
  23. J. P. Hansen and I. R. McDonald, Theory of Simple Liquids, 4th ed. (Academic Press, London, 2013).
  24. J. Müller and M. Schmidt, companion paper, Quantum statistical mechanics: Gauge invariance, operator shifting, hyperdensity functionals, and nonequilibrium sum rules, Phys. Rev. E 114, 024130 (2026).
  25. I. Bloch, J. Dalibard, and W. Zwerger, Many-body physics with ultracold gases, Rev. Mod. Phys. 80, 885 (2008).
  26. J.-Y. Choi, S. Hild, J. Zeiher, P. Schauß, A. Rubio-Abadal, T. Yefsah, V. Khemani, D. A. Huse, I. Bloch, and C. Gross, Exploring the many-body localization transition in two dimensions, Science 352, 1547 (2016).
  27. P. Bordia, H. Lüschen, S. Scherg, S. Gopalakrishnan, M. Knap, U. Schneider, and I. Bloch, Probing slow relaxation and many-body localization in two-dimensional quasiperiodic systems, Phys. Rev. X 7, 041047 (2017).
  28. M. Yan, H. Y. Hui, M. Rigol, and V. W. Scarola, Equilibration dynamics of strongly interacting bosons in 2D lattices with disorder, Phys. Rev. Lett. 119, 073002 (2017).
  29. M. Yan, H.-Y. Hui, and V. W. Scarola, Dynamics of disordered states in the Bose-Hubbard model with confinement, Phys. Rev. A 95, 053624 (2017).
  30. P. Łydżba, M. Mierzejewski, M. Rigol, and L. Vidmar, Generalized thermalization in quantum-chaotic quadratic Hamiltonians, Phys. Rev. Lett. 131, 060401 (2023).
  31. R. Patil and M. Rigol, Eigenstate thermalization for local versus translationally invariant observables, arXiv:2602.09087.
  32. R. Patil and M. Rigol, Eigenstate thermalization, arXiv:2604.11872.
  33. A. Palamara, F. Plastina, A. Sindona, and I. D'Amico, Thermal-density-functional-theory approach to quantum thermodynamics A, Phys. Rev. A 110, 062203 (2024).
  34. A. Palamara, F. Plastina, A. Sindona, and I. D' Amico, Full quantum work statistics for non-homogeneous many-body systems, Quantum Sci. Technol. 11, 025055 (2026).
  35. C. A. Ullrich, A snapshot of time-dependent density-functional theory, APL Comp. Phys. 1, 020901 (2025).
  36. M. Schmidt, Power functional theory for many-body dynamics, Rev. Mod. Phys. 94, 015007 (2022).
  37. P. A. M. Dirac, The Principles of Quantum Mechanics, 4th ed. (Clarendon Press, Oxford, 1958).
  38. J. J. Sakurai, Advanced Quantum Mechanics (Addison-Wesley, Reading, MA, 1973).
  39. E. Fick and G. Sauermann, The Quantum Statistics of Dynamic Processes (Springer, Berlin, 1990).
  40. A. Anderson, Canonical transformations in quantum mechanics, Ann. Phys. (NY) 232, 292 (1994).
  41. H. Goldstein, C. Poole, and J. Safko, Classical Mechanics (Addison-Wesley, New York, 2002).
  42. R. Kubo, Statistical-mechanical theory of irreversible processes. I. General theory and simple applications to magnetic and conduction problems, J. Phys. Soc. Jpn. 12, 570 (1957).
  43. D. Petz and G. Toth, The Bogoliubov inner product in quantum statistics, Lett. Math. Phys. 27, 205 (1993).
  44. G. Sauermann, H. Turschner, and W. Just, Selfconsistent approximations in Mori's theory, Physica A 225, 19 (1996).
  45. F. Sammüller, S. Robitschko, S. Hermann, and M. Schmidt, Hyperdensity functional theory of soft matter, Phys. Rev. Lett. 133, 098201 (2024).
  46. F. Sammüller and M. Schmidt, Why hyperdensity functionals describe any equilibrium observable, J. Phys.: Condens. Matter 37, 083001 (2025).
  47. N. D. Mermin, Thermal properties of the inhomogeneous electron gas, Phys. Rev. 137, A1441 (1965).
  48. I. V. Tokatly, Quantum many-body dynamics in a Lagrangian frame: I. Equations of motion and conservation laws, Phys. Rev. B 71, 165104 (2005).
  49. I. V. Tokatly, Quantum many-body dynamics in a Lagrangian frame: II. Geometric formulation of time-dependent density functional theory, Phys. Rev. B 71, 165105 (2005).
  50. I. V. Tokatly, Time-dependent deformation functional theory, Phys. Rev. B 75, 125105 (2007).
  51. C. A. Ullrich and I. V. Tokatly, Nonadiabatic electron dynamics in time-dependent density-functional theory, Phys. Rev. B 73, 235102 (2006).
  52. W. Tarantino and C. A. Ullrich, A reformulation of time-dependent Kohn-Sham theory in terms of the second time derivative of the density, J. Chem. Phys. 154, 204112 (2021).
  53. M.-L. M. Tchenkoue, M. Penz, I. Theophilou, M. Ruggenthaler, and A. Rubio, Force balance approach for advanced approximations in density functional theories, J. Chem. Phys. 151, 154107 (2019).
  54. K. J. Daas, S. Crisostomo, and K. Burke, Ensemble time-dependent density functional theory, Phys. Rev. Lett. 137, 028002 (2026).
  55. M. S. Green, Markoff random processes and the statistical mechanics of time-dependent phenomena. II. Irreversible processes in fluids, J. Chem. Phys. 22, 398 (1954).
  56. W. De Roeck and C. Maes, Quantum version of free-energy–irreversible-work relations, Phys. Rev. E 69, 026115 (2004).
  57. L. C. Céleri and Ł. Rudnicki, Gauge-invariant quantum thermodynamics: Consequences for the first law, Entropy 26, 111 (2024).
  58. G. F. Ferrari, Ł. Rudnicki, and L. C. Céleri, Quantum thermodynamics as a gauge theory, Phys. Rev. A 111, 052209 (2025).
  59. N. Nguyen-Tran-Thanh, T. Nguyen-Xuan, and H. Pham-Van, Gauge theory of orientation in anisotropic fluids, Phys. Rev. E 113, 025401 (2026).
  60. H. Pham-Van, Unified gauge-geometry symmetry for equilibrium statistical mechanics, Phys. Rev. E 113, 054134 (2026).
  61. T. Maruyama, T. Seto, V. Zaverkin, and H. Christiansen, A Leibniz rule of distributional pairing and hyperforce sum rule, arXiv:2603.01519.
  62. H. Pham-Van, Quantum statistical-gauge geometry, Phys. Rev. E 113, 064134 (2026).
  63. H. Pham-Van, Statistical-gauge covariance in open quantum systems, Phys. Rev. E (2026), doi:10.1103/vghs-2pdw.
  64. https://www.mschmidt.uni-bayreuth.de/pubs/quantum_gauge.nb.

Outline

Information

Sign In to Your Journals Account

Filter

Filter

Article Lookup

Enter a citation