Early universe's 'little red dots' may be black hole stars

4 days ago (science.org)

The JWST is discovering so many new things and blowing the lid off of so many theories. It's pretty incredible.

This list doesn't even include the red dots: https://www.astronomy.com/science/the-10-greatest-jwst-disco...

  • My favorite is that there are probably primordial black holes, which is exciting because they are a good dark matter candidate. They could have other neat implications too, like being common enough that we might some day find one within visiting range. Being able to examine one directly could allow us to “finish physics.”

    Note that many if not most variations on the Big Bang and inflation predict them but we have yet to directly see them. What JWST has found is indirect evidence they’re out there.

    • This PBS Spacetime video pours some cold water on the black holes as dark matter hypothesis:

      https://youtu.be/qy8MdewY_TY?si=9jc_a7IAm4qrhfNX

      It’s 4 years old; I don’t know if this JWST finding changes anything. I do know we have finally found some (one?) intermediate-mass black holes in the interim, but I don’t know if that changes it either.

      The possibility it leaves open for “Planck relics” is interestingly exotic

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    • I wonder if the time estimates of ~13.8 billion years hold up for the big bang in the future. I remember a physicist talking about time and space being fuzzy in the real early universe.

Just in case you somehow don’t know what a Black Hole Star is, check out Kurzgesagt’s video about them <https://www.youtube.com/watch?v=aeWyp2vXxqA>

Forgive me for being off topic, but I must say how astonished and happy I am that Soundgarden's nonsense song title from 1994 now is a real science concept:

https://youtu.be/3mbBbFH9fAg?si=cnB-WVsE9OLuF-GK

If true, does this give more credence to the so called "Blowtorch Theory" that was featured on HN a couple of months back?

Upon reading the title, I would have expected some gravitational redshift to be part of the explanation, which made me wonder—are we sure none of that deep gravity well effect is contributing to the redness? That said, I understand the community tends to favor AGN-related causes: rapid Doppler broadening of emission lines, infrared dust reprocessing, and cosmological redshift seem to account for most of what’s observed.

  • The redshift in the early universe is actually why the JWST is an infrared telescope. Hubble was limited to higher wavelengths and couldn't see objects that were excessively redshifted.

    But no in this case these objects are red even in comparison to nearby objects.

  • There's already a ton of redshift from the universe expanding, so they're definitely correcting their spectra for some amount of redshift. I'd love to know if there's a way to tell the two sources of redshift apart, or if significant redshift from climbing away from the hole just makes it look a smidge farther away.

    But honestly I'd guess that the light is emitted too far from the horizon to be redshifted very much by the black hole.

  • I'm no astronomer trying to have work published, but wouldn't a mistake like that be one of the most obvious things to attempt to test your own work against before releasing the results? Is the fear of releasing an obvious mistake and the damage to one's reputation just not present anymore, or is first to publish so critical that mistakes are forgiven? To me, if I was going to present a paper that goes against existing conventional thinking, I'd want to make sure my paper stood up to the most rigorous review including (especially?) from HN commenters.

    • Fair point — I don't think gravitational redshift was completely ignored, but perhaps it was ruled out early and not discussed in the public-facing article. In most astrophysical observations, especially with JWST, cosmological redshift and AGN mechanisms usually dominate the interpretation, but I agree: when something challenges conventional thinking, even “obvious” effects deserve a clear mention or elimination.

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How many other "known" things in astronomy are actually something else entirely when you throw better instruments at them

  • That's not an astronomy thing, that's a general science thing. Everything is just an educated guess until we build something to study it in more detail. And when we confirm or disprove something, we can make new guesses using the added info.

I wish we could have faster than light travel by compressing space somehow, go to these 50 billion light years away objects and actually verify if they are a galaxy or not. Even if you could insta teleport to every object, I think it would still take an infinite amount of time to visit every star, every galaxy and every planet for just 10 seconds

  • I predict that if faster than light travel is possible, we will have it within our lifetimes, perhaps even as soon as 20 years ago.

  • You can't get there because you can't out run the growth of space itself and even if you got there, whatever it was you came to see was there at last 50 billion years ago and wouldn't look the same, or possibly no longer exist.

    • Not 50 billion years ago because the universe is only about 13.8 billion years old as of current thinking. Space has been expanding in the time it's taken light to travel so "light years away = time ago light was emitted" gets increasingly wrong at longer distances

Making progress on these key issues in galaxy evolution and black hole growth is exactly the kind of research that will not happen (or at minimum be extremely limited) under the current administration’s grant cancellations, funding cuts, and staffing reductions at the NSF and NASA, the two of which account for almost all of US astronomy research funding.

  • It's just depressing. Such a moronic & self sabotaging policy. I'd say people should look at the evidence on the returns from NSH & NSF funding but if people cared about basing policy on evidence we wouldn't be here in the first place.

    • How is studying a black hole going to make the rich richer? If it's not, then it's not worth doing. It doesn't take a rocket scientist to figure that out. All of you poors should be less concerned about make believe spacey stuff, and figure out how to give more of your money to the rich.

      I wish I was joking

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  • We're finally at the point where instruments like JWST can answer decade-old questions