Recommendable! Given that the Big Bang theory overall is actually quite implausible, black holes may help to expose this inconvenient fact! What came before the Big Bang? God?
"We still don’t know how the first black holes formed — or when they formed. To have gotten as big as they seem to be today, they may have emerged right after the universe was formed, a new study concludes. ...
The oldest black hole we know of is 13.80 billion years old, forming just 690 million years after the big bang. It’s also a massive black hole, at 800 million times the mass of the Sun. ...
How did a black hole so massive form so early in the universe, what did it form from? Plus, it’s unlikely that we found the oldest black hole, there are possibly even older ones out there, and our current understanding of the universe struggles to explain something like that. Meanwhile, on the other end of the scale, there could be some small early black holes (as highlighted by observations from ESA’s Gaia). These black holes seem too small to have formed from stars, so how did they form exactly? ..."
The oldest black hole we know of is 13.80 billion years old, forming just 690 million years after the big bang. It’s also a massive black hole, at 800 million times the mass of the Sun. ...
How did a black hole so massive form so early in the universe, what did it form from? Plus, it’s unlikely that we found the oldest black hole, there are possibly even older ones out there, and our current understanding of the universe struggles to explain something like that. Meanwhile, on the other end of the scale, there could be some small early black holes (as highlighted by observations from ESA’s Gaia). These black holes seem too small to have formed from stars, so how did they form exactly? ..."
From the abstract (I have to admit this is a tough one loaded with technical terms etc. and no attempt to explain the relevance to a non-expert audience):
"We explore the observational implications of a model in which primordial black holes (PBHs) with a broad birth mass function ranging in mass from a fraction of a solar mass to ∼106 M⊙, consistent with current observational limits, constitute the dark matter (DM) component in the universe. The formation and evolution of dark matter and baryonic matter in this PBH-Λ cold dark matter (ΛCDM) universe are presented. In this picture, PBH-DM mini-halos collapse earlier than in standard ΛCDM, baryons cool to form stars at z ∼ 15–20, and growing PBHs at these early epochs start to accrete through Bondi capture. The volume emissivity of these sources peaks at z ∼ 20 and rapidly fades at lower redshifts. As a consequence, PBH DM could also provide a channel to make early black hole seeds and naturally account for the origin of an underlying DM halo–host galaxy and central black hole connection that manifests as the Mbh–σ correlation. To estimate the luminosity function and contribution to integrated emission power spectrum from these high-redshift PBH-DM halos, we develop a halo occupation distribution model. In addition to tracing the star formation and reionization history, it permits us to evaluate the cosmic infrared and X-ray backgrounds. We find that accretion onto PBHs/active galactic nuclei successfully accounts for the detected backgrounds and their cross-correlation, with the inclusion of an additional IR stellar emission component. Detection of the deep IR source count distribution by the James Webb Space Telescope could reveal the existence of this population of high-redshift star-forming and accreting PBH DM."
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