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
  • Open Access

Dark energy and QCD instanton vacuum in a Friedmann-Lemaître-Robertson-Walker universe

M. M. Musakhanov*

  • *Contact author: musakhanov@gmail.com

Phys. Rev. D 112, 123501 – Published 1 December, 2025

DOI: https://doi.org/10.1103/x2b7-5y1r

Abstract

The standard model of the universe, λCDM, is based on the Friedmann-Lemaître-Robertson-Walker metric with a flat three-dimensional coordinate space and the Friedmann equations Navas et al. [Phys. Rev. D 110, 030001 (2024).]. The cosmological constant λ provides the cancellation of the matter field contributions in the flat (Minkowski) space, as was proposed long ago in 1967 by Zeldovich for the first time to our knowledge Zeldovich [JETP Lett. 6, 316 (1967)]; see also Krasinski and Zeldovich [Sov. Phys. Usp. 11, 381 (1968)]. The dynamical dark energy appears on the surface of the vacuum energy of matter fields at the flat (Minkowski) space. Within the Standard Model, the gluon Yang-Mills (YM) fields are playing a specific role since the properties of their vacuum, where there is the presence of the gluon condensate, provide the nonperturbative vacuum energy. It is natural to apply the successful instanton liquid model of the QCD vacuum and its lowest excitations. Our aim is to calculate the contribution of gluon YM fields to the dark energy density. We find that the universe metric is generating the QCD vacuum excitation, which gives the contribution to the dark energy density. But this one may hardly play a central role in the dynamics of the universe, since its timescale is too small. We also find the equation-of-state parameters w0=−1,wa=0 in accordance with λCDM, while the newest data, analyzed at Shajib and Frieman [Phys. Rev. D 112, 063508 (2025).], give them at least in the range −0.91<w0<−0.73,−1.05<wa<−0.65. They are requesting a contribution from an ultralight scalar such as an axion, or from YM field topological configurations with the nontrivial holonomy due to the deviation from a pure de Sitter state Van Waerbeke and Zhitnitsky [DESI results and dark energy from QCD topological sectors, arXiv:2506.14182.].

View figure in article

Physics Subject Headings (PhySH)

Article Text

References (36)

  1. S. Navas et al. (Particle Data Group), Review of particle physics, Phys. Rev. D 110, 030001 (2024).
  2. Y. B. Zeldovich, Cosmological constant and elementary particles, JETP Lett. 6, 316 (1967), http://jetpletters.ru/ps/1673/article_25521.shtml.
  3. A. Krasinski and Y. B. Zeldovich, The cosmological constant and the theory of elementary particles, Sov. Phys. Usp. 11, 381 (1968).
  4. J. Bjorken, Emergent gauge bosons, arXiv:hep-th/0111196.
  5. J. D. Bjorken, The classification of universes, arXiv:astro-ph/0404233.
  6. R. Schutzhold, Small cosmological constant from the QCD trace anomaly?, Phys. Rev. Lett. 89, 081302 (2002).
  7. F. R. Klinkhamer and G. E. Volovik, Self-tuning vacuum variable and cosmological constant, Phys. Rev. D 77, 085015 (2008).
  8. F. R. Klinkhamer and G. E. Volovik, Dynamic vacuum variable and equilibrium approach in cosmology, Phys. Rev. D 78, 063528 (2008).
  9. F. R. Urban and A. R. Zhitnitsky, The cosmological constant from the QCD Veneziano ghost, Phys. Lett. B 688, 9 (2010).
  10. F. R. Urban and A. R. Zhitnitsky, The QCD nature of dark energy, Nucl. Phys. B835, 135 (2010).
  11. A. R. Zhitnitsky, Inflaton as an auxiliary topological field in a QCD-like system, Phys. Rev. D 89, 063529 (2014).
  12. A. R. Zhitnitsky, Dynamical de Sitter phase and nontrivial holonomy in strongly coupled gauge theories in an expanding universe, Phys. Rev. D 92, 043512 (2015).
  13. A. O. Barvinsky and A. R. Zhitnitsky, Inflation and gauge field holonomy, Phys. Rev. D 98, 045008 (2018).
  14. L. Van Waerbeke and A. Zhitnitsky, DESI results and dark energy from QCD topological sectors, arXiv:2506.14182.
  15. I. L. Shapiro, Effective action of vacuum: Semiclassical approach, Classical Quantum Gravity 25, 103001 (2008).
  16. T. C. Kraan and P. van Baal, Periodic instantons with nontrivial holonomy, Nucl. Phys. B533, 627 (1998).
  17. K. M. Lee and C. h. Lu, SU(2) calorons and magnetic monopoles, Phys. Rev. D 58, 025011 (1998).
  18. M. Abdul Karim et al. (DESI Collaboration), DESI DR2 results. II. Measurements of baryon acoustic oscillations and cosmological constraints, Phys. Rev. D 112, 083515 (2025).
  19. A. J. Shajib and J. A. Frieman, Scalar-field dark energy models: Current and forecast constraints, Phys. Rev. D 112, 063508 (2025).
  20. E. V. Shuryak, The role of instantons in quantum chromodynamics. 1. Physical vacuum, Nucl. Phys. B203, 93 (1982).
  21. D. Diakonov and V. Y. Petrov, Instanton based vacuum from Feynman variational principle, Nucl. Phys. B245, 259 (1984).
  22. D. Diakonov, Instantons at work, Prog. Part. Nucl. Phys. 51, 173 (2003).
  23. E. Shuryak, Lectures on nonperturbative QCD (nonperturbative topological phenomena in QCD and related theories), arXiv:1812.01509.
  24. L. D. Faddeev, In search of multidimensional solitons, (JINR, Dubna, 1976), in 40 Years in Mathematical Physics (World Scientific Publishing, Singapore, 1995), pp. 369–381.
  25. L. D. Faddeev, Some comments on the many dimensional solitons, Lett. Math. Phys. 1, 289 (1976).
  26. R. Jackiw and C. Rebbi, Vacuum periodicity in a Yang-Mills quantum theory, Phys. Rev. Lett. 37, 172 (1976).
  27. G. V. Dunne and B. Tekin, Calorons in Weyl gauge, Phys. Rev. D 63, 085004 (2001).
  28. M. C. Chu, J. M. Grandy, S. Huang, and J. W. Negele, Evidence for the role of instantons in hadron structure from lattice QCD, Phys. Rev. D 49, 6039 (1994).
  29. D. Diakonov, M. V. Polyakov, and C. Weiss, Hadronic matrix elements of gluon operators in the instanton vacuum, Nucl. Phys. B461, 539 (1996).
  30. A. A. Migdal and M. A. Shifman, Dilaton effective Lagrangian in gluodynamics, Phys. Lett. 114B, 445 (1982).
  31. V. A. Novikov, M. A. Shifman, A. I. Vainshtein, and V. I. Zakharov, Are all hadrons alike?, Nucl. Phys. B191, 301 (1981).
  32. M. A. Shifman, Anomalies and low-energy theorems of quantum chromodynamics, Sov. Phys. Usp. 32, 289 (1989).
  33. J. R. Ellis and J. Lanik, Is scalar gluonium observable?, Phys. Lett. B 150, 289 (1985).
  34. D. Kharzeev, E. Levin, and K. Tuchin, QCD in curved space-time: A conformal bag model, Phys. Rev. D 70, 054005 (2004).
  35. M. C. Tichy and P. Faccioli, The scalar glueball in the instanton vacuum, Eur. Phys. J. C 63, 423 (2009).
  36. H. B. Meyer and M. J. Teper, Glueball Regge trajectories and the Pomeron: A lattice study, Phys. Lett. B 605, 344 (2005).

Outline

Information

Sign In to Your Journals Account

Filter

Filter

Article Lookup

Enter a citation