A comment on metric vs metric-affine gravity

Creative Commons License

Lındström U. G., Sarıoğlu B. Ö.

PHYSICS LETTERS B, cilt.836, 2023 (SCI-Expanded) identifier identifier identifier

  • Yayın Türü: Makale / Kısa Makale
  • Cilt numarası: 836
  • Basım Tarihi: 2023
  • Doi Numarası: 10.1016/j.physletb.2022.137619
  • Dergi Adı: PHYSICS LETTERS B
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, Aerospace Database, Chemical Abstracts Core, INSPEC, zbMATH, Directory of Open Access Journals
  • Orta Doğu Teknik Üniversitesi Adresli: Evet

Özet

We consider the sum of the Einstein-Hilbert action and a Pontryagin density (PD) in arbitrary even dimension D >= 4. All curvatures are functions of independent affine (torsionless) connections only. In arbitrary even dimension, not only in D = 4n, these first order PD terms are shown to be covariant divergences of "Chern-Simons" currents. The field equation for the connection leads to it being LeviCivita, and to the metric and affine field equations being equivalent to the second order metric theory. This result is a counterexample to the theorem stating that purely metric and metric-affine models can only be equivalent for Lovelock theories. (c) 2022 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/). Funded by SCOAP(3).