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Updated: May 8, 2026
11:20
Investigation of Early Plasma Evolution Induced by Ultrashort Laser Pulses
Published on: July 2, 2012
Precursor of inflation
Inyong Cho1, Hyeong-Chan Kim, Taeyoon Moon
1Institute of Convergence Fundamental Studies and School of Liberal Arts, Seoul National University of Science and Technology, Seoul 139-743, Korea. iycho@seoultech.ac.kr
Physical Review Letters
|September 3, 2013
Summary
This study presents a nonsingular early Universe model using scalar fields in modified gravity, naturally leading to cosmic inflation without needing quantum gravity for the preinflationary phase.
Area of Science:
- Cosmology
- Theoretical Physics
Background:
- Understanding the very early Universe and the origin of cosmic inflation remains a key challenge in modern physics.
- Existing models often rely on quantum gravity for the preinflationary epoch, which is not yet experimentally verified.
Purpose of the Study:
- To investigate a nonsingular initial state of the Universe that naturally leads to cosmic inflation.
- To explore inflation within the framework of Eddington-inspired Born-Infeld gravity.
Main Methods:
- The study employs a scalar field with a quadratic potential within Eddington-inspired Born-Infeld gravity.
- Analysis focuses on the curvature of the initial state determined by the scalar field's mass scale.
Main Results:
- A nonsingular initial state is identified where the curvature is below the Planck scale.
- This model avoids the necessity of quantum gravity for the preinflationary stage, irrespective of energy density.
- The initial state evolves into a prolonged inflationary period, consistent with chaotic inflation models.
Conclusions:
- The proposed model offers a viable alternative for understanding the Universe's earliest moments.
- It provides a natural mechanism for cosmic inflation without invoking quantum gravity at extremely high energy densities.
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