Even if their theory is correct and their measurements (a linear trend) accurately reflect time slowing down, the universe would have only slowed down 81,140m/s total (average .073% per year) over 6000 years making the time required for visible light from distant galaxies to reach faster by only 0.79%, meaning there is still light from 13.2 billion light years away that we can observe, but the universe is 6000 years old
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