Story perspectives

Study Suggests Universe's Expansion May Be Slowing Down

11/8/2025

Summary

Story summary

A Yonsei University study suggests the expansion of the Universe may be slowing, challenging the view that it accelerates because of dark energy.
Researchers analyzed data from Type Ia supernovae and found the brightness depends on the age of the progenitor stars.
After correcting for this age-related bias, the data favor decelerating expansion and could reshape ideas about dark energy and the Universe’s fate.

History

Historical Context

In 1929, Edwin Hubble's groundbreaking observations established Hubble's Law, demonstrating that galaxies recede from Earth at speeds proportional to their distances, thus revealing the universe's expansion. This foundational work built on earlier theories by Alexander Friedmann and Georges Lemaître. A recent study from Yonsei University challenges the notion of accelerating expansion, suggesting a decelerating universe, which could reshape our understanding of cosmic evolution.

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Story summary

A Yonsei University study suggests the expansion of the Universe may be slowing, challenging the view that it accelerates because of dark energy.
Researchers analyzed data from Type Ia supernovae and found the brightness depends on the age of the progenitor stars.
After correcting for this age-related bias, the data favor decelerating expansion and could reshape ideas about dark energy and the Universe’s fate.

1 / 2