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James Webb Telescope discovers some quasars that seem to exist in isolation
- xqcgrek2 2y agoThis is clickbait / regurgitating a press release from a university outfit tl;dr there's a lot of dust around the quasar Astronomy has a big problem with people overhyping their results
- pbhjpbhj 2y agoThey sound like quasars that have consumed everything around them?
- ramraj07 2y agoOnce you look at the math, you realize that no matter how hard they try, black holes can’t suck everything around them.
- hparadiz 2y agoIt probably got kicked out of it's host galaxy during a merger.
- haccount 2y agoThese are quasars in 13+ billion years old footage. Using the official age of the universe we need to then form the quasar in a dense matter region and then speedrun a galaxy merger that ejects the relevant quasar out into sparse space, all of that in a few hundred million years only. Using contemporary cosmology practices I suggest we add a Dark Age to everything observed. Yes the age of the quasar is 13 billion something years in the axis of regular time, but due to observations disagreeing with this timeline we can just keep adding years to any given observation in the Dark Age, complex time axis, until the problem is solved
- api 2y agoPrimordial black holes I believe are the answer to this, but I’m not a pro physicist. AFAIK we have seen indirect evidence of their existence with Webb. They could explain some of this early structure.
- mr_mitm 2y agoPlease respect the guidelines of this community. This is really unnecessary. > Be kind. Don't be snarky. Converse curiously; don't cross-examine. Edit out swipes. > Comments should get more thoughtful and substantive, not less, as a topic gets more divisive. > Please don't fulminate. Please don't sneer, including at the rest of the community.
- scotty79 2y agoNot sure how you read into any of those things in the parent comment. Dark Age he's suggesting already exists in cosmology in form of short period of rapid inflation that started and ended for no reason other than without it we can't fit inflationary cosmology to observation at all.
- mr_mitm 2y agoThe GP poster is clearly making fun of dark matter and dark energy, supporting the typical trope among dark matter skeptics that both are mere crutches because most cosmologists refuse to find modifications to gravity for whatever reason. This interpretation is in line with other comments made in this thread by the same account (the one about "dark suction" and others). Inflation has no influence on galaxy formation. Its duration was also a tiny fraction of a second, not years. It's also the first time I have heard it being associated with the term "dark age". The only actual "dark age" in cosmology in the common sense of the term is the period between reionization and first light by stars. Nothing to do with the quasars we are discussing here. It's really hard for me to read the comment in the way you suggest.
- scotty79 2y ago
- renegade-otter 2y agoI was just watching this: https://www.youtube.com/watch?v=c1sZpSoMq5g https://www.youtube.com/watch?v=c1sZpSoMq5g And, apparently, poor lonely black holes can evaporate over time?
- api 2y agoNot if their Hawking temperature is below the CMB, which is the case I think for any above asteroid mass. As the universe cools and the CMB drops that threshold drops. The big black holes will last n^n^n… ridiculous amounts of time.
- speakeron 2y agoJust one ^n. Supermassive black holes are expected to have completely evaporated by 10^100 years.
- kolanos 2y agoEvaporate into what? Nothingness?
- api 2y agoEnergy, over a very long period of time. Remember that mass and energy are equivalent. Hawking temperature is inversely proportional to black hole size, so the bigger the hole the "colder" it is. The largest black holes will start evaporating very slowly once the CMB drops below their temperature. A tiny micro black hole, if one were created, would evaporate almost instantly converting 100% of its mass into energy, basically a bomb. E.g. a 1kg micro black hole smaller than an electron would have a yield similar to a small hydrogen bomb, most of which would be released as ultra high energy gamma rays. Black holes are awesome. In some ways they are the most extreme things in the universe, the extreme-est of extreme physics. The mass-energy density required to create them is so far beyond anything humanly possible that trying to do so with, for example, hydrogen bombs would be not much better than trying to do it by squeezing really hard with your hand. It requires things like the first few milliseconds after the Big Bang (if primordial black holes exist) or collapsing massive stars. To give a sense of this density: a black hole with the mass of the Earth would be about the size of a marble (Schwartzchild radius). Inside of course there's either a true singularity or -- if certain theories of quantum gravity are correct -- a region of some kind of maximum-theoretical-density matter. (Some theories predict that true singularities don't exist.) If somehow someday it were possible to create or control them, it would be possible to access energies far beyond fusion or even antimatter-driven reactions... think perfect direct mass-energy conversion with near 100% efficiency.
- haccount 2y agoMaybe a theory of hard-to-observe Dark Suction will come to the rescue
- api 2y agoIf they did they’d be invisible, which is why isolated primordial black holes with a variety of masses are a dark matter candidate. A quasar would be one with a giant accretion disk right?
- smolder 2y agoIs that necessarily true in the earliest moments of the universe? Probably there are good reasons for it to be so that I don't understand, but then most of what cosmologists understand about the period that JWST looks back to is from extrapolating backwards, and it seems like the new observations it has enabled keep disagreeing with previous assumptions. Anyway, I really look forward to finding out what improvements to theory can be made to better explain anomalies like these lonely quasars or the apparently overdeveloped young galaxies.
- saagarjha 2y agoQuasars are bright because they are surrounded by material that accretes and shines. If they are isolated then they are just quiet black holes.
- pbhjpbhj 2y agoWell, the accretion disk surely runs out at some point, and just before that point, shouldn't it look like a quasar in surprisingly empty space?
- saagarjha 2y agoThe brightness comes from the accretion disk.
- pbhjpbhj 2y agoYes, I understand that, but what is the failure mode - is it gradual or rapid? If it is rapid, then the system keeps shining even when it appears almost empty. If gradual, then I probably need to revisit what I learned of quasars done decades ago...
- saagarjha 2y agoLet me know what you find ;)
- Sharlin 2y agoQuasars don't and can't even consume a significant fraction of their host galaxies' mass, never mind other nearby galaxies.
- haccount 2y ago[flagged]
- ironSkillet 2y agoRather than just making a conspiratorial post, could you explain these alternative theories and why you see this article as strong evidence against existing mainstream theories?
- exe34 2y agoeven better, he could offer an alternative that doesn't fall on its face based on existing observations.
- haccount 2y agoMy contribution is that current theory falls on it its face based on existing observations. That stands on its own. That I don't provide a viable replacement is a refutation of absolutely nothing.
- exe34 2y agoI think we already know that - otherwise nobody would be trying to gather more observations with the hope of throwing up a clue as to what the solution would be. the current theories are favoured purely because they work in more cases than any alternatives. nobody is saying they are 100% correct. so I'm not sure your contribution is terribly novel.
- haccount 2y agoI don't keep much track of the alternative theories, my feeds are dialed for space news and every second article is paraphrased as "new JWST observations doesn't fit current theories" It's constantly finding something too big, too old, too early and in the wrong place. As for dark matter, repeat failure of observation in both man made experiments and inconsistencies in the cosmic distribution. If we called it the "ad hoc variable representing the will of the gods lightly pushing shit around" it would more accurately fit observations. Something spins too fast, arbitrary dial the will of god to keep shit together in that particular place. Inconsistent with elsewhere? No problem the Gods will it differently there, maybe the average distribution of worshippers is lower in that galaxy? Contemporary evidence is the the same for both formulations of the dark mystery variable that forces observation to adhere to the fraying theory. At some point the accumulated problems grow so large you don't need to be on a cosmologist payroll to recognize it for being legacy bullshit grandfathered into the present.
- OgsyedIE 2y agoI would assume that given the extreme redshift this can be explained by the combination of acoustic oscillation overdensities and gravothermal catastrophe but there is probably some unmentioned reason why it can't.
- ajross 2y agoThis sounds like a line stolen from an old Star Trek script, FWIW. For those who need more context, the ideas here are real: https://physics.stackexchange.com/questions/249679/gravothermal-catastrophe-looking-for-simple-explanation https://physics.stackexchange.com/questions/249679/gravother... https://en.wikipedia.org/wiki/Baryon_acoustic_oscillations https://en.wikipedia.org/wiki/Baryon_acoustic_oscillations
- orbisvicis 2y agoWait - If I throw a bowling ball really fast in a vacuum, does its temperature increase?
- ajross 2y agoYes. But if you take an existing slow ("cold") bowling ball in orbit around a mass concentration and hit it with a fast ("hot") one, it will be moving faster immediately. But now it's trajectory will take it out into a longer orbit where it slows down and spends more time moving near apogee, where it looks "cold". So you end up with this paradoxical situation where a "hot" mass starts to interact with a "cold" one and ends up making it even colder, so it collapses.
- orbisvicis 2y agoI'm having trouble wrapping my head around how a measure with an absolute value (temperature) can relate to a measure with no absolute reference (velocity). In a purely inelastic collision, all the energy should be transfered to velocity, and thus the temperature not increase. A pure elastic collision would be the opposite. Similarly, if the ball and launcher are moving away relative to a given point, and the ball is launched towards that given point so that it is moving slower relatively, did the temperature increase or decrease? And with rotational velocity, if you double the radius the velocity halves because the total energy (and therefore temperature?) remains constant. Imagine if I used an inertialess drive to move faster - would my temperature have increased?
- benjamaan 2y ago[flagged]
- AlexAndScripts 2y agoBTW we all know this is LLM generated. It's really obvious. Please stop (entirely; don't just get better at hiding it).
- beastman82 2y agoIf Halton Arp were still here he'd be smiling
- dfilppi 2y ago[dead]
- ck2 2y agoso much new JWST stuff, it's fantastic first brown dwarfs seen in other galaxies too https://bsky.app/profile/philplait.bsky.social/post/3l7bssmhq222t https://bsky.app/profile/philplait.bsky.social/post/3l7bssmh...