medium · Act science
The 'Big Bang' Model: The universe began as a singularity and has been expanding and cooling ever since. The 'Steady State' Model: The universe has always existed in the same state, with new matter being created as it expands to keep density constant.
If the 'Cosmic Microwave Background' radiation is discovered to be a uniform 'glow' of heat left over from a hot early universe, which model is supported?
- The 'Big Bang' Model, because it predicts a specific period of intense heat in the past that would leave such a lingering signature.
- The 'Big Bang' Model, because it is the only theory that is compatible with the laws of thermodynamics and the expansion of the galaxies.
- The 'Steady State' Model, because the uniform nature of the radiation suggests that the universe is perfectly balanced in its current form.
- Neither model, because radiation is a property of energy that can be generated by various astronomical objects like pulsars and quasars.
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