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Updated: Sep 30, 2025
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Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
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Cosmological milestones, conformal frameworks and quiescent cosmology
Susan M Scott1, Philip Threlfall1
1Centre for Gravitational Astrophysics, Research School of Physics, College of Science, The Australian National University, Canberra, Australian Capital Territory 2601, Australia.
Summary
Quiescent cosmology proposes a smooth Big Bang origin for our universe. This study analyzes cosmological milestones and conformal frameworks within FRW models, informing future research on the universe's evolution.
Area of Science:
- Theoretical Physics
- Cosmology
- Astronomy
Background:
- Understanding the universe's origin and fate is a key driver in physics and astronomy.
- Various cosmological milestones (Big Bangs, Big Crunches, etc.) are defined in scientific literature.
- Quiescent cosmology posits a smooth, regular Big Bang, with evolution driven by gravitational attraction.
Purpose of the Study:
- To analyze the relationship between cosmological milestones and conformal frameworks.
- To establish general properties of FRW models admitting conformal frameworks.
- To inform future development of the quiescent cosmology program.
Main Methods:
- Analysis of Friedmann-Lemaître-Robertson-Walker (FRW) solutions.
- Investigation of conformal frameworks, such as the Isotropic Past Singularity (IPS).
- Examination of energy conditions and physical reasonableness of FRW models.
Main Results:
- Established general properties of FRW models that admit conformal frameworks.
- Determined which FRW models satisfy energy conditions, indicating physical reasonableness.
- Linked cosmological milestones with conformal frameworks for FRW solutions.
Conclusions:
- The study provides insights into the quiescent cosmology program.
- Results contribute to understanding the initial and final states of the universe.
- The geometric definitions used are independent of specific models and equations of state.
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