Two astrophysicists at Spain's Instituto de Astrofísica de Canarias analyzed data from the James Webb Space Telescope — the most powerful telescope available — on 31 galaxies with an average redshift of 7.3 (when the universe was 700 million years old, according to the standard model). "We found that they are on average ~600 million years old old, according to the comparison with theoretical models based on previous knowledge of nearby galaxies..."

"If this result is correct, we would have to think about how it is possible that these massive and luminous galaxies were formed and started to produce stars in a short time. It is a challenge."

But "The fact that some of these galaxies might be older than the universe, within some significant confidence level, is even more challenging." The most extreme case is for the galaxy JADES-1050323 with redshift 6.9, which has, according to my calculation, an age incompatible to be younger than the age of the universe (800 million years) within 4.7-sigma (that is, a probability that this happens by chance as statistical fluctuation of one in one million).

If this result is confirmed, it would invalidate the standard Lambda-CDM cosmological model. Certainly, such an extraordinary change of paradigm would require further corroboration and other stronger evidence. Anyway, it would be interesting for other researchers to try to explain the Spectral Energy Distribution of JADES-1050323 in standard terms, if they can ... and without introducing unrealistic/impossible models of extinction, as is usually done.
The findings are published in the journal Monthly Notices of the Royal Astronomical Society.