1994/08/25 by J. S. F. Chan, J S F Chan, R. B. Mann +1
Physics and Astronomy · #Action (physics) #Black Holes and Theoretical Physics #Cosmology #Cosmology and Gravitation Theories #Dilaton #Equation of state #Field equation #Gravitation #Hydrostatic equilibrium #Noncommutative and Quantum Gravity Theories #Tensor (intrinsic definition) #f(R) gravity #gr-qc
paper · pdf · doi:10.1088/0264-9381/12/2/006
published as Class.Quant.Grav.12:351-372,1995 · 34 pages
arxiv created 1994/08/25 · openalex publication_date 1995/02/01 · arxiv updated 2010/04/06 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
The actions of the `R=T' and string-inspired theories of gravity in (1+1) dimensions are generalized into one single action which is characterized by two functions. We discuss differing interpretations of the matter stress--energy tensor, and show how two such different interpretations can yield two different sets of field equations from this action. The weak-field approximation, post-Newtonian expansion, hydrostatic equilibrium state of a star and two-dimensional cosmology are studied separately by using the two sets of field equations. Some properties in the `R=T' and string-inspired theories are shown to be generic in the theory induced by the generalized action.