Particle Production in f(R) Gravity during Structure Formation

Abstract

We study particle production in infrared-modified gravitational theories in the contemporary universe. It is shown that in astronomical systems with rising mass density, the curvature scalar may oscillate with very high frequency. These oscillations lead to efficient particle production and in an interesting range of model parameters could be a source of energetic cosmic rays. This effect either excludes some models of modified gravity or suggests a new mechanism of cosmic ray production.

16 pages, 3 figures

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• Dark energy cosmology: the equivalent description via different theoretical models and cosmography tests
• Models of f(R) Cosmic Acceleration that Evade Solar-System Tests
• Disappearing cosmological constant in f(R) gravity
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Cited by in corpus (8)

• $\Lambda$CDM Bounce Cosmology without $\Lambda$CDM: the case of modified gravity
• Chameleons in the Early Universe: Kicks, Rebounds, and Particle Production
• Jeans Instability in Classical and Modified Gravity
• Spherically Symmetric Solutions in F(R) Gravity and Gravitational Repulsion
• Gravitational instability in oscillating background
• No Cosmic Rays from Curvature Oscillations during Structure Formation with $F(R)$-gravity
• Cosmic ray production in modified gravity
• Construction of f(R) Gravity Models