Has JWST discovered a primordial black hole and how many posts will it take before this thread is derailed?

[sjastro]

Primordial black holes are theorized to have formed shortly after the Big Bang when quantum fluctuations in the inflaton field, the hypothetical quantum field which drives inflation resulting in a very brief period of exponential inflation of the universe. Where there are quantum fluctuations creating regions of over-density, these collapse after inflation due to gravity to form primordial black holes.

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"JWST black hole discovery Redefines Cosmic Origins"

Explore the groundbreaking JWST black hole discovery of A2744-QSO1—reshaping our understanding of galaxy formation and the early universe.

nasaspacenews.com

If primordial black holes do exist it would favour the theory that supermassive black holes in the centre of galaxies were produced before the formation of the galaxy.

 

[Larniavc]

If primordial black holes do exist it would favour the theory that supermassive black holes in the centre of galaxies were produced before the formation of the galaxy.

I thought that PBHs were tiny (relatively). Why would that imply they might be responsible for galactic centre black holes?

 

[sjastro]

I thought that PBHs were tiny (relatively). Why would that imply they might be responsible for galactic centre black holes?

PBHs can have masses up to intermediate supermassive black holes and grow further through merging and accretion of primeval hydrogen and helium.
While this is not a mainstream theory, the trouble with the accepted model of black hole growth based purely on the accretion of stars or gas, it is far too slow for the formation of supermassive black holes in galaxies which as JWST has shown can form early in the universe's history.

 

[sjastro]

Here is the spectrum of A2744-QSO1.

Some notes on the spectrum.

The spectrum of A2744-QSO1, a quasar observed at a redshift of z = 7.0451, was obtained using the James Webb Space Telescope's NIRSpec instrument. This deep spectrum, equivalent to approximately 38 hours of integration time, reveals several key features.(Nature)

• Broad Hydrogen Emission Lines: Prominent broad Hβ and Hα lines are present, with the Hβ line exhibiting a full width at half maximum (FWHM) of 2,800 ± 250 km/s. This indicates high-velocity gas in the vicinity of the supermassive black hole. (Nature)
• High Reddening: The spectrum shows significant dust extinction, quantified as A_V ≈ 3, suggesting that the quasar is heavily obscured by dust. (Nature)
• Lack of Strong Metal Lines: The absence of strong metal emission lines implies a low-metallicity environment, consistent with an early stage in cosmic chemical evolution. (arXiv)
• High Black Hole Mass and Luminosity: The black hole mass is estimated to be 4 × 10⁷ M_☉, with a bolometric luminosity of (1.1 ± 0.3) × 10⁴⁵ erg/s, indicating rapid accretion at about 30% of the Eddington limit. (Nature)

These spectral characteristics suggest that A2744-QSO1 is a rapidly growing supermassive black hole in the early universe, potentially representing a transitional phase between black hole seeds and the first luminous quasars. (arXiv)

For a detailed view of the spectrum, refer to Figure 2 in the Nature article: (Nature).(Nature)

The Eddington limit mentioned in the notes occurs when the gravitational potential energy of infalling accreting matter is converted into radiation and heat. The resulting outward radiation pressure counters the gravitational pull on the infalling matter and slows the accretion rate.
When the outward radiation pressure equals the gravitational pull the Eddington limit is reached.