eprintid: 10190500 rev_number: 6 eprint_status: archive userid: 699 dir: disk0/10/19/05/00 datestamp: 2024-04-11 13:50:47 lastmod: 2024-04-11 13:50:47 status_changed: 2024-04-11 13:50:47 type: article metadata_visibility: show sword_depositor: 699 creators_name: Böhmer, Christian G creators_name: Jensko, Erik title: A New 2D Formulation of Modified General Relativity ispublished: inpress divisions: UCL divisions: B04 divisions: C06 divisions: F59 note: © 2024 The Authors. Fortschritte der Physik published by Wiley-VCH GmbH. This is an open access article under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/). abstract: It is well known that the Einstein–Hilbert action in two dimensions is topological and yields an identically vanishing Einstein tensor. Consequently one is faced with difficulties when formulating a non‐trivial gravity model. The authors present a new, intrinsically two‐dimensional, approach to this problem based on the Einstein action. This yields a well defined variational approach which results in new field equations that break diffeomorphism invariance. This proposed approach does not require the introduction of additional scalar fields, nor the use of conformal transformations. However, how including conformal counter terms leads to equivalent results is shown. In doing so, an explanation for why previous approaches worked can be provided. Solutions to the field equations are briefly discussed. date: 2024-04-06 date_type: published publisher: Wiley official_url: http://dx.doi.org/10.1002/prop.202300216 oa_status: green full_text_type: pub language: eng primo: open primo_central: open_green verified: verified_manual elements_id: 2266361 doi: 10.1002/prop.202300216 lyricists_name: Boehmer, Christian lyricists_id: CGBOH42 actors_name: Flynn, Bernadette actors_id: BFFLY94 actors_role: owner full_text_status: public publication: Fortschritte der Physik article_number: 2300216 citation: Böhmer, Christian G; Jensko, Erik; (2024) A New 2D Formulation of Modified General Relativity. Fortschritte der Physik , Article 2300216. 10.1002/prop.202300216 <https://doi.org/10.1002/prop.202300216>. (In press). Green open access document_url: https://discovery.ucl.ac.uk/id/eprint/10190500/1/A%20New%202D%20Formulation%20of%20Modified%20General%20Relativity.pdf