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Groundbreaking Study Confirms Big Bang's Cosmic Background Temperature

11/2/2025

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Summary

Story summary

Keio University researchers led by Tatsuya Kotani and Tomoharu Oka measured the cosmic microwave background temperature at redshift z = 0.89 as 5.13 ± 0.06 K.
The temperature is nearly double the current 2.7 K, confirming the Big Bang–predicted scaling of CMB temperature with redshift.
The findings, published in The Astrophysical Journal, used Atacama Large Millimeter/submillimeter Array (ALMA) data and established a benchmark for future cosmological research.

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Story summary

Keio University researchers led by Tatsuya Kotani and Tomoharu Oka measured the cosmic microwave background temperature at redshift z = 0.89 as 5.13 ± 0.06 K.
The temperature is nearly double the current 2.7 K, confirming the Big Bang–predicted scaling of CMB temperature with redshift.
The findings, published in The Astrophysical Journal, used Atacama Large Millimeter/submillimeter Array (ALMA) data and established a benchmark for future cosmological research.