Publications

Citation

BibTex format

@article{Bassani:2024:10.1142/s0218271823501134,
author = {Bassani, PM and Magueijo, J},
doi = {10.1142/s0218271823501134},
journal = {International Journal of Modern Physics D: Gravitation, Astrophysics and Cosmology},
title = {Unimodular-like times, evolution and Brans–Dicke gravity},
url = {http://dx.doi.org/10.1142/s0218271823501134},
volume = {33},
year = {2024}
}
Download

RIS format (EndNote, RefMan)

TY  - JOUR
AB  - In unimodular-like theories, the constants of nature are demoted from pre-given parameters to phase space variables. Their canonical duals provide physical time variables. We investigate how this interacts with an alternative approach to varying constants, where they are replaced by dynamical scalar fields. Specifically, we investigate the Brans–Dicke theory of gravity and its interaction with clocks dual to the cosmological constant, the Planck mass, etc. We crucially distinguish between the different role of Newton’s G in this process, leading to the possibility of local Lorentz invariance violation. A large number of possible theories emerge, for example where the Brans–Dicke coupling, ω, depends on unimodular-like times (in a generalization of scalar-tensor theories), or even become the dual variable to unimodular-like clocks ticking variations in other demoted constants, such as the cosmological constant. We scan the space of possible theories and select those most interesting regarding the joint variations of the Brans–Dicke ω and other parameters, (such as the cosmological constant); and also regarding their energy conservation violation properties. This ground work is meant to provide the formalism for further developments, namely regarding cosmology, black holes and the cosmological constant problem.
AU  - Bassani,PM
AU  - Magueijo,J
DO  - 10.1142/s0218271823501134
PY  - 2024///
SN  - 0218-2718
TI  - Unimodular-like times, evolution and Brans–Dicke gravity
T2  - International Journal of Modern Physics D: Gravitation, Astrophysics and Cosmology
UR  - http://dx.doi.org/10.1142/s0218271823501134
UR  - http://hdl.handle.net/10044/1/110007
VL  - 33
ER  -
Download

Note to staff:  Adding new publications to a research group

  1. Log in to Symplectic.
  2. Click on Menu > Create Links
  3. Choose what you want to create links between – in this case ‘Publications’ and ‘Organisational structures’.
  4. Choose the organisational structure (research group) into which you want to link the publications and check the box next to it.
  5. Now check the box of any publication you want to add to that group. You can use the filters to find what you want and select multiple publications if necessary. 
  6. Scroll to the bottom and click the blue ‘Create new link’ button to link them.
  7. The publications will be added to the group, and will be displayed on the group publications feed within 24 hours (it is not immediate).

Any problems, talk to Tim Evans or the Faculty Web Team.