91–100 of 186 posts
> Over the course of a year, Chandra stared at the cosmic lens for two weeks — one of its longest observation campaigns yet — and collected 19 X-ray photons coming from a galaxy called UHZ1, at a redshift of 10.1. Those 19 high-octane photons most likely came from a growing black hole that existed fewer than half a billion years after the Big Bang, making it by far the most distant X-ray source ever detected. This bl…
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Your comment is a bit strange. Light doesn't travel as photons. Photons exclusively exist at the site and instant of detection of the wave of probability of detection that light really travels as. When light is redshifted, it loses energy, therefore the wavelength becomes longer.
That is not the current understanding of quantum mechanics, as far as I know. Wave/particle dualism says that different experiments can either view light as a wave or a particle (never both) and that speaking about the nature of light when an experiment is not being performed is non-scientific by definition. Importantly, light very much behaves like a conventional wave in many real experiments - the interferometer ex…
silly downvoters.
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Experimentally one never observes waves. Light is detected based on its interaction with electrons and that is always by an electron absorbing a quanta of energy, not via some continuous process as would be the case with waves. Classically one can imagine that as if electron was hit by a particle. But then we have light diffraction and interference, which classically is described as a wave. So from a classical point…
> So from a classical point of view light travels as a wave but interact as a particle. And the classical point of view is wrong . Photons resemble classical particles in a few respects, and classical waves in a few others, but at the end of the day they're neither. > Still the point stands that we never observe light directly but only through its effects on electrons and other charged particles. This is true of lite…
and yes direct observation exists. that's what measurement is. and that's all you can ever "observe" unless you incorporate the wavefunction, which also doesn't "exist".
Can someone who really knows this stuff clarify my understanding? I've been given to understand that black holes remain a physics theory that has not been directly observed or proven. I thought that we had a fair amount of observational evidence that suggests their existence, but no "smoking gun" proof of it, and that these types of "observed a black hole" articles are a little misleading - that in reality, what was…
A part of CCC[1] is giant black holes outlasting the end of the universe to be around for the beginning of the next one. Is this a potential explanation? [1] https://en.wikipedia.org/wiki/Conformal_cyclic_cosmology
It's pretty cool how much JWST has caught in such a short amount of time. Give it another 5-10 years and we may have some absolutely groundbreaking new celestial theories.
It's really worthwhile to compare it to the hubble in that regard. Pre-hubble, the question was whether the universe would contract into a big crunch, expand slower and slower forever, or balance out somehow in the middle. Then hubble got a good look at universal expansion and we noticed it was speeding up and now we've got Lambda-CDM from that. From this we know what the long term fate of the universe is. That there…
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Jesse, what are you talking about?
Well, Mr White, if you look at all of the "weirdness" in physics with theories coming out because "the math says it's possible", then you'd see that it would be much more simple if we were not allowed to have negative numbers because we're only using u64 integers. we'd have more digits for precision as well.
- Blackholes are collapsed masses. In our phase of the universe, they are normally the results of supernovae but only because today stars are the only source of dense masses.
- Because the total mass of the universe is constant and the early universe has a volume of dozen orders of magnitude smaller than the universe in later stage (the universe we normally observe), collapsed masses should happen much more likely than in later stage.
- Those masses do not necessarily come from the stars, which are masses with a visible fusion processes but could come directly from mass-lumps, left after the Big Bang.
- In fact, I think the idea of a super homogenous universe right after the Big Bang is suspect. Even the CMB is only homogeneous on (very) large scale (3000 mega parsecs), ways too big for blackholes.
- Therefore, I think after the Big Bang, there should be a large number of primordial blackholes.
- We can only observe blackholes with an accretion disk, but the primordial blackholes with no visible accretion will stay invisible unless there is a collision/fusion in progress.
Consequently, we will find a lot more blackholes in the early universe, the more we look. They are super massive because of the bias: only supermassive blackholes with accretion disk were producing radiation, powerful enough so we can detect with our current technology.
Maybe I’m a bit naive here, but I thought finding of many supermassive back holes in the very early universe should be expected, and not a surprise. My chain of thoughts is following: - Blackholes are collapsed masses. In our phase of the universe, they are normally the results of supernovae but only because today stars are the only source of dense masses. - Because the total mass of the universe is constant and the…
Maybe I’m a bit naive here, but I thought finding of many supermassive back holes in the very early universe should be expected, and not a surprise. My chain of thoughts is following: - Blackholes are collapsed masses. In our phase of the universe, they are normally the results of supernovae but only because today stars are the only source of dense masses. - Because the total mass of the universe is constant and the…
Would it be enough to account for the "Dark Matter" conundrum ?