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A simple description of the 3 k cosmic microwave background
Science (New York, N.Y.)
|February 29, 1980
Summary
This study presents the Milne model, a special relativistic view of cosmic expansion. It explains the cosmic microwave background as red-shifted photons from receding matter, approximating an ever-expanding open universe.
Area of Science:
- Cosmology
- Relativity
Background:
- The expansion of the universe is a fundamental concept in modern cosmology.
- General relativity provides the standard framework for describing the universe's evolution (Friedmann models).
Purpose of the Study:
- To develop an intuitive model for cosmic expansion using special relativity.
- To explore the relationship between special relativistic and general relativistic cosmological models.
Main Methods:
- Utilizing special relativity and a hypothetical observer in a Lorentz frame.
- Describing cosmic microwave background photons as red-shifted remnants of emitted radiation.
Main Results:
- The developed model, known as the Milne model, offers a special relativistic perspective on cosmic expansion.
- The Milne model approximates an open universe that expands indefinitely.
- This model represents an extreme case of a Friedmann universe at vanishing matter density.
Conclusions:
- The Milne model provides an accessible framework for understanding aspects of cosmic expansion.
- The model's accuracy in approximating an open universe increases over time.
- It highlights the connection between special relativity and the broader context of general relativistic cosmology.
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