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f(R) Theories
Antonio De Felice1, Shinji Tsujikawa1
1Department of Physics, Faculty of Science, Tokyo University of Science, 1-3, Kagurazaka, Shinjuku-ku, Tokyo, 162-8601 Japan.
Living Reviews in Relativity
|February 10, 2017
Summary
f(R) theories offer simple modifications to General Relativity, with applications in cosmology and gravity. This review explores their use in inflation, dark energy, and gravity constraints, detailing observational distinctions from General Relativity.
Area of Science:
- Cosmology
- Modified Gravity Theories
Background:
- f(R) theories are a prominent class of modified gravity models.
- They represent simple deviations from General Relativity.
Purpose of the Study:
- To review applications of f(R) theories in cosmology and gravity.
- To discuss observational and experimental methods for distinguishing f(R) theories from General Relativity.
- To explore extensions to other modified gravity theories.
Main Methods:
- Review of existing literature on f(R) theories.
- Analysis of applications in inflation, dark energy, and gravitational constraints.
- Discussion of observational and experimental tests.
- Exploration of extensions to Brans-Dicke and Gauss-Bonnet gravity.
Main Results:
- f(R) theories have diverse applications including inflation and dark energy.
- Various methods exist to observationally and experimentally differentiate f(R) theories from General Relativity.
- Models satisfying both cosmological and local gravity constraints are addressed.
Conclusions:
- f(R) theories provide a viable framework for addressing cosmological puzzles and gravity modifications.
- Distinguishing modified gravity from General Relativity is crucial for understanding the universe.
- Further research into specific f(R) models and their observational signatures is warranted.
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