1979, Robert A. Freitas Jr., Xenology: An Introduction to the Scientific Study of Extraterrestrial Life, Intelligence, and Civilization, (Chapter 4. Xenology: The Context of the Universe)https://www.bibliotecapleyades.net/vida_alien/xenology/04.0.htm The energy corresponds to a constant, uniform temperature of 2.7 K. This actual relic of the primeval ylem superexplosion strongly affirms the Big Bang theories, and appears to verify the Cosmological Principle mentioned earlier.
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