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Cosmic Explosions, Life in the Universe, and the Cosmological Constant
Tsvi Piran1, Raul Jimenez2,3, Antonio J Cuesta4
1Racah Institute of Physics, The Hebrew University, Jerusalem 91904, Israel.
Physical Review Letters
|March 12, 2016
Summary
Gamma-ray bursts (GRBs) pose a threat to life. Life survival is maximized in Lambda-dominated universes, suggesting our universe
Area of Science:
- Cosmology
- Astrobiology
- Astrophysics
Background:
- Gamma-ray bursts (GRBs) are high-energy astronomical events.
- GRBs can pose a significant threat to complex life on planets through atmospheric interactions.
Purpose of the Study:
- To determine the cosmological conditions that maximize the chances of complex life surviving GRBs.
- To explore the relationship between the cosmological constant (Λ) and life's habitability.
Main Methods:
- Utilized cosmological N-body simulations.
- Incorporated recent data on GRB rates and extinction probabilities.
- Analyzed a cold dark matter model with a cosmological constant.
Main Results:
- Life survival to GRBs is favored in Lambda-dominated universes.
- The likelihood of life survival is dependent on the value of Λ and the age of the Universe.
- Current cosmic conditions appear to be favorable for life, balancing GRB exposure and star availability.
Conclusions:
- Advanced life may be more probable in universes with a specific cosmological constant.
- Our universe's current state seems to optimize conditions for life by minimizing cosmic threats and maximizing habitable stars.
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