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Study Challenges Universe's Expansion: Deceleration Detected

11/14/2025

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Summary

Story summary

A Yonsei University study led by astronomer Young-Wook Lee challenges the view that the universe is expanding and accelerating.
The apparent acceleration is an illusion from star ages used to measure distances.
The findings indicate the universe began decelerating about 1.5 billion years ago, potentially leading to a big crunch scenario.
The study was published in Monthly Notices of the Royal Astronomical Society.

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Story summary

A Yonsei University study led by astronomer Young-Wook Lee challenges the view that the universe is expanding and accelerating.
The apparent acceleration is an illusion from star ages used to measure distances.
The findings indicate the universe began decelerating about 1.5 billion years ago, potentially leading to a big crunch scenario.
The study was published in Monthly Notices of the Royal Astronomical Society.