The most exciting idea to me that JWST has bolstered is primordial black holes. Many models already predict them but JWST has provided the first good indirect evidence in the form of too-early galaxies. The models that predict PBHs predict that.
If they exist, they would not be constrained to stellar mass and above. There could be a population of little black holes floating around. Anything under the mass of a decent size asteroid would have evaporated by now but anything that mass and above would still exist.
They are a dark matter candidate, and one that doesn’t require new physics. But even if they don’t account for a significant amount of dark matter they still probably exist.
The most exciting thing about PBHs is that one or more may exist in our solar system. They might have been captured over billions of years. Finding them would be incredibly challenging, especially if they are low mass, but if we did it means we could directly examine and experiment on a black hole.
That’s something that could allow us to test theories of quantum gravity and things like string theory, and maybe more. A black hole could be like a Rosetta Stone of deep fundamental physics.
gbjcantab 2 hours ago [-]
This is one of my favorite phenomena: again in again, across various fields of study, breakthroughs in discovery allow us to go from relative ignorance to a level of knowledge and understanding that enables clear and clean conceptual models; then, as we learn even more, we realize how much more complex and weird and multifaceted reality really is.
It’s like a Dunning-Kruger effect on a field-wide scale, but in a good way. Rather than an example of hubris, it’s an opportunity for awe.
qsera 2 hours ago [-]
>It’s like a Dunning-Kruger effect on a field-wide scale, but in a good way.
But not in in medical field. The unjustifiable over confidence can lead to application of bad things on a generational and population wide scale, damaging many many generations of human beings.
sdoering 1 hours ago [-]
WTF. We have such great medical advancement in cancer treatments, vaccines, reconstructive surgery h just to name a few.
Not sure what you are referring to, but the only unjustifiable things in the (so called) medical field are snake oil sales men trying to make a quick buck by instilling a fear of science into people's minds. Like anti-vax idiots. Or homeopathic bullshit.
juanani 57 minutes ago [-]
[dead]
6thbit 58 minutes ago [-]
That’s a beautiful article showcasing our predicament in having access to more information about the universe.
Now i have to be the one to ask the dumb defensive question:
what makes us so certain that we can trust what we see on James Webb?
Can we definitely discard a measurement problem?
neffy 33 minutes ago [-]
Some of the Hubble results were also raising questions. At the same time, I read one of the papers on the galaxy stuff, and what struck me was they were identifying galaxy shapes by counting the pixels each galaxy had, so there are definitely some question marks over how they do some of this.
jdw64 3 hours ago [-]
As observations become too numerous, it seems like it can be summarized as there now being too many possible candidate explanations. As data increases and becomes clearer, more and more things don't fit the existing theories.
What are the current theories explaining the early universe? What happened to the Big Bang? I only studied astronomy up to an undergraduate level, so I don't really know.
I imagine that various non-uniform gases were scattered around, and due to spatial distortions, those uniform gas regions clumped together, forming stars and other structures. Perhaps the expansion of space wasn't uniform either—it expanded unevenly, sometimes bulging, and when space expands or contracts, energy is generated, causing spacetime changes to shake the field, and that shaking might have created matter. Maybe the dynamic interaction between changing spacetime and fields revealed the energy stored in the field in the form of particles.
What do scientists think about this in modern cosmology? My knowledge is far too limited and I lack intuition, but reading science-related articles always excites me. Maybe it's because I still have some childlike curiosity left in me
tigerlily 1 hours ago [-]
I took a good long look at the CMB picture, including the caption. It basically says the Universe was one big hot apparently uniform ball at one stage.
I don't know what conditions were like before that stage, but like Eric Idle says, nothing can come from nothing.
Dark energy is a horse shit name for a theory that was horse shit to begin with. The Universe is probably just inhomogeneous, like your intuition is saying.
tigerlily 54 minutes ago [-]
I will say that the current and future telescope lineup is amazing and is bound to reveal: even more fascinating insights and mysteries!
jvs76 2 hours ago [-]
I dont think about it because my days are occupied by very specific problems. Theory of Bounded Rationality and its implications apply.
jdw64 2 hours ago [-]
Right. When you don't have any breathing room, it's hard to think about anything else. That's why I take about two hours a day to just watch the news and clear my head. I'd probably forget all about it too if I were working 70-hour weeks on a contracted project, haha. Hang in there. Have a good day
ben_w 1 hours ago [-]
With the caveat I'm summarising from what PBS Space Time and Dr Becky* say:
• Big Bang: we can only see back to surface of last scattering, i.e. the CMB, extrapolating backwards goes "???" at much the same point as it did a few decades back because we still have not unified quantum mechanics and general relativity
• CMB should only have isotope distribution of Big Bang nucleosynthesis, that hasn't changed in the last decades, dunno if that's what you meant by "various non-uniform gases were scattered around"?
• Variations in density of CMB do exist, key phrase is "Baryon acoustic oscillations", while they're very small magnitude they're also massive in distance scale, so they're how galactic clusters formed (that scale rather than stars directly): https://en.wikipedia.org/wiki/Baryon_acoustic_oscillations
• Re: "Perhaps the expansion of space wasn't uniform either": I heard about specifically "Timescape Cosmology", but a quick search says that's part of a broader category of inhomogeneous cosmologies: https://en.wikipedia.org/wiki/Inhomogeneous_cosmology#Timesc...
• Re: "and when space expands or contracts, energy is generated": no, general relativity does not in general conserve energy, and it is related to the curvature of spacetime. Simple example is that the photons in the CMB have much less energy to us than they did to the atoms they were emitted from**: https://www.youtube.com/watch?v=04ERSb06dOg
* I assuming I'm correctly judging the level and attention to detail they're providing, given the detail they put in and references to specific research publications. My degree is Software Engineering.
** There's also a Veritasium video about this, but to me Veritasium feels like a BBC 2 evening popular science show, so I'm not as confident about recommending it.
jdw64 1 hours ago [-]
thanks!!
dvh 2 hours ago [-]
Only two things are infinite: the cosmos, and a web designer’s obsession with discovering new ways to break scrolling.
beng-nl 1 hours ago [-]
And we’re not sure about the cosmos.
CrzyLngPwd 1 hours ago [-]
And no one can be sure about the cosmos :-p
34 minutes ago [-]
phyzix5761 2 hours ago [-]
> Faced with observations of early black holes and galaxies that weren’t expected to exist, scientists have come up with a wealth of new theories to explain them. Now they just need to figure out which ones are true.
This subtitle really bothers me. Science isn't about finding out what is true. Science is about finding out what is false and building models to explain the rest. We can never confidently say we know something to be true because that closes the door for future science to disprove our beliefs and that's exactly the purpose of science.
The best we can do is come up with increasingly more useful models accepting that in the end all models are wrong but different models are useful for different purposes.
Tanath 46 minutes ago [-]
Hypotheses are made for a reason though. Science is still about finding what's true, and ruling out what's not is part of the process/method for doing so. Sometimes all the alternatives to the truth are ruled out and we know the truth. Scientific revolutions happen sometimes, but they still need to explain everything the old theories explained. The newer theories may still be wrong, but in different and hopefully fewer ways. It's important to keep the scope of what's been demonstrated/tested in mind to not be misled about what truths have been established. Newton's physics is still largely true within the scope of everyday experience, for example.
Rendered at 12:58:37 GMT+0000 (Coordinated Universal Time) with Vercel.
If they exist, they would not be constrained to stellar mass and above. There could be a population of little black holes floating around. Anything under the mass of a decent size asteroid would have evaporated by now but anything that mass and above would still exist.
They are a dark matter candidate, and one that doesn’t require new physics. But even if they don’t account for a significant amount of dark matter they still probably exist.
The most exciting thing about PBHs is that one or more may exist in our solar system. They might have been captured over billions of years. Finding them would be incredibly challenging, especially if they are low mass, but if we did it means we could directly examine and experiment on a black hole.
That’s something that could allow us to test theories of quantum gravity and things like string theory, and maybe more. A black hole could be like a Rosetta Stone of deep fundamental physics.
It’s like a Dunning-Kruger effect on a field-wide scale, but in a good way. Rather than an example of hubris, it’s an opportunity for awe.
But not in in medical field. The unjustifiable over confidence can lead to application of bad things on a generational and population wide scale, damaging many many generations of human beings.
Not sure what you are referring to, but the only unjustifiable things in the (so called) medical field are snake oil sales men trying to make a quick buck by instilling a fear of science into people's minds. Like anti-vax idiots. Or homeopathic bullshit.
what makes us so certain that we can trust what we see on James Webb? Can we definitely discard a measurement problem?
What are the current theories explaining the early universe? What happened to the Big Bang? I only studied astronomy up to an undergraduate level, so I don't really know.
I imagine that various non-uniform gases were scattered around, and due to spatial distortions, those uniform gas regions clumped together, forming stars and other structures. Perhaps the expansion of space wasn't uniform either—it expanded unevenly, sometimes bulging, and when space expands or contracts, energy is generated, causing spacetime changes to shake the field, and that shaking might have created matter. Maybe the dynamic interaction between changing spacetime and fields revealed the energy stored in the field in the form of particles.
What do scientists think about this in modern cosmology? My knowledge is far too limited and I lack intuition, but reading science-related articles always excites me. Maybe it's because I still have some childlike curiosity left in me
I don't know what conditions were like before that stage, but like Eric Idle says, nothing can come from nothing.
Dark energy is a horse shit name for a theory that was horse shit to begin with. The Universe is probably just inhomogeneous, like your intuition is saying.
• Big Bang: we can only see back to surface of last scattering, i.e. the CMB, extrapolating backwards goes "???" at much the same point as it did a few decades back because we still have not unified quantum mechanics and general relativity
• CMB should only have isotope distribution of Big Bang nucleosynthesis, that hasn't changed in the last decades, dunno if that's what you meant by "various non-uniform gases were scattered around"?
• Variations in density of CMB do exist, key phrase is "Baryon acoustic oscillations", while they're very small magnitude they're also massive in distance scale, so they're how galactic clusters formed (that scale rather than stars directly): https://en.wikipedia.org/wiki/Baryon_acoustic_oscillations
https://www.youtube.com/watch?v=PPpUxoeooZk
https://www.youtube.com/watch?v=LRUTnoveZs8
• Re: "Perhaps the expansion of space wasn't uniform either": I heard about specifically "Timescape Cosmology", but a quick search says that's part of a broader category of inhomogeneous cosmologies: https://en.wikipedia.org/wiki/Inhomogeneous_cosmology#Timesc...
https://www.youtube.com/watch?v=SXg6YVcdOcA
https://www.youtube.com/watch?v=JlNVZz5D6WE
• Re: "and when space expands or contracts, energy is generated": no, general relativity does not in general conserve energy, and it is related to the curvature of spacetime. Simple example is that the photons in the CMB have much less energy to us than they did to the atoms they were emitted from**: https://www.youtube.com/watch?v=04ERSb06dOg
* I assuming I'm correctly judging the level and attention to detail they're providing, given the detail they put in and references to specific research publications. My degree is Software Engineering.
** There's also a Veritasium video about this, but to me Veritasium feels like a BBC 2 evening popular science show, so I'm not as confident about recommending it.
This subtitle really bothers me. Science isn't about finding out what is true. Science is about finding out what is false and building models to explain the rest. We can never confidently say we know something to be true because that closes the door for future science to disprove our beliefs and that's exactly the purpose of science.
The best we can do is come up with increasingly more useful models accepting that in the end all models are wrong but different models are useful for different purposes.