2000/04/04 by Eduardo Guendelman, E. I. Guendelman, Guendelman, E. I.
Earth and Planetary Sciences · Physics and Astronomy · #Cosmology and Gravitation Theories #Earth Systems and Cosmic Evolution #FOS: Physical sciences #General Relativity and Quantum Cosmology (gr-qc) #Relativity and Gravitational Theory #gr-qc
paper · pdf · doi:10.48550/arxiv.gr-qc/0004011
Contribution to the conference "Energy Densities in the Universe", Les Arcs, France, January 2000
arxiv created 2000/04/04 · openalex publication_date 2000/04/04 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The possibility of mass in the context of scale-invariant, generally covariant theories, is discussed. Scale invariance is considered in the context of a gravitational theory where the action, in the first order formalism, is of the form S = ∫ L1 Φd4x + ∫ L2√(-g)d4x where Φ is a density built out of degrees of freedom independent of the metric. For global scale invariance, a "dilaton" ϕ has to be introduced, with non-trivial potentials V(ϕ) = f1eαϕ in L1 and U(ϕ) = f2e2αϕ in L2. This leads to non-trivial mass generation and a potential for ϕ which is interesting for inflation. The model after ssb can be connected to the induced gravity model of Zee, which is a successful model of inflation. Models of the present universe and a natural transition from inflation to a slowly accelerated universe at late times are discussed.