Astrophysicists have revealed the possible fate of the sun if an ancient small black hole enters it. According to research published on the preprint server arXiv, the star has the potential to transform into something like a red giant star. A primordial black hole is a hypothetical black hole that formed during the first moments of the universe’s existence. Many theoretical models assume that primordial black holes are common, so the probability that a star will capture one of them is considered high. Such a star is called a Hawking star. According to a new study, black holes initially have no visible impact on stars like the Sun. However, over time, it absorbs material from the star’s core and grows larger. If the black hole originally had a mass of about 1 billion solar masses, it would take less than 500 million years for the entire star to disappear.

If the black hole has a mass less than 1 trillion solar masses, the situation looks slightly different. The absorption of matter causes the star’s core to heat up and expand, forming a giant red star that is cooler and redder than a normal red giant star. Additionally, turbulence within the core may cause surface activity that can be observed using asteroseismology techniques. Results from astroseismological studies indicate that either there are likely no black holes inside the Sun, or that black holes are very small.

source: https://arxiv.org/abs/2312.07647