16 ms·

Is it reasonable to view the Cosmic Microwave Background Radiation as being the limit of this? The remains of the big bang, maximally scaled up and red shifted

by xen0 3y ago

Is it reasonable to view the Cosmic Microwave Background Radiation as being the limit of this? The remains of the big bang, maximally scaled up and red shifted as far as things can be today?

drorco 3y ago
So essentially one giant blob of cosmic background radiation was at the time its light was emitted, the size of an atom or so?
- ben_w 3y ago
  Kinda but different scale, the CMB era universe was about 1100 times smaller than that now, so still huge. There may be a neutrino background behind the CMB, where the universe was even smaller, and the gravitational wave background behind that with even more of a size difference.
  - bozhark 3y ago
    Plays right into the white hole theory, interesting
    - bloopernova 3y ago
      As in a white hole is the big bang? That has a kind of poetic symmetry to it, with black holes (big crunches?) being the end, and white holes being the beginning of our particular universe. But our universe has black holes in it. Forgive the layman thinking, but does that mean we're just one of an infinite series of "nested" universes?
      - pelorat 3y ago
        The energy in our universe is not unlimited, so perhaps each black hole spawns a new universe, and each has less and less energy in it. Think about, WHY is there a certain amount of energy in the universe? Why not more or less. Maybe it's just universes all the way down.
  - bloopernova 3y ago
    Would the universe in those other 2 older events have been 2 orders of magnitude smaller still? Have there been any estimates made for the sizes in each "event"? Are there even more events further back, or is the next one after gravity the big bang? What a fascinating subject, thank you for expanding my own little universe!
    - ben_w 3y ago
      I'm skim-reading on mobile right now, so here's some more information, but I didn't see anything about how much the universe expanded since 1 second after the big bang, which is the relevant number for the neutrino background: https://en.wikipedia.org/wiki/Cosmic_neutrino_background https://en.wikipedia.org/wiki/Cosmic_neutrino_background https://en.wikipedia.org/wiki/Neutrino_decoupling https://en.wikipedia.org/wiki/Neutrino_decoupling and for gravity: https://en.wikipedia.org/wiki/Gravitational_wave_background https://en.wikipedia.org/wiki/Gravitational_wave_background
- devoutsalsa 3y ago
  The cosmic microwave background radiation didn’t appear until the universe was about 380,000 years old. https://en.m.wikipedia.org/wiki/Cosmic_microwave_background https://en.m.wikipedia.org/wiki/Cosmic_microwave_background
  - oneshtein 3y ago
    So CMB is just 14B years old? Then why we see objects older than CMB? Moreover, why these older than CMB objects appearing in front of CMB?
    - jvanderbot 3y ago
      We dont see galaxies older than CMB.
      - oneshtein 3y ago
        Yep. This is the problem. Why CMB is emitted at the edge of our Universe only? Where are atoms, which produced the CMB?
        bigbillheck 3y ago
        > Why CMB is emitted at the edge of our Universe only? I thought CMB was emitted everywhere.
        oneshtein 3y ago
        CMB is produced by atoms, right? We see darker/lighter regions in CMB, so we should see a transition somewhere. 300M years is very short period of time, unless everything cooled very very uniformly, which is not the case. Sometimes, somewhere there must be a galaxy past CMB.
        bigbillheck 3y ago
        > a transition somewhere A transition from what to what? > which is not the case. Why not? > Sometimes, somewhere there must be a galaxy past CMB. If there is we'd have to wait for the light from it to get to us, by which time the CMB will have receded further and it would then be in front of the CMB.
__MatrixMan__ 3y ago
I think there's a coherent explanation of the cmb be had there, but it's not the conventional explanation. Under this alternative, the universe cooled to light transparency some time before the moment depicted by the cmb, and anything "further away" than that hugely magnified scene just happened outside of our light cone. That is to say, it's "elsewhere" (a technical term (https://web.phys.ksu.edu/fascination/Interlude1.pdf https://web.phys.ksu.edu/fascination/Interlude1.pdf)). Seems to me that in this alternative, cosmic expansion could be explained as gravitational attraction between elsewhere-matter and matter in our light cone. Imagine there's some argument to be made for why this is not the case, but I don't know it. It would require a bit of explaining re: why that point in history and not some other? - Is it that the maximal distance is constant and that the cmb is subtly changing in ways we havent noticed (as the point of most-distant-past moves forward in time) - Or maybe something caused the speed of light to change at that time, pruning the rest of the universe from our view.

by xen0 3y ago

Is it reasonable to view the Cosmic Microwave Background Radiation as being the limit of this? The remains of the big bang, maximally scaled up and red shifted as far as things can be today?

drorco 3y ago

So essentially one giant blob of cosmic background radiation was at the time its light was emitted, the size of an atom or so?

ben_w 3y ago
Kinda but different scale, the CMB era universe was about 1100 times smaller than that now, so still huge. There may be a neutrino background behind the CMB, where the universe was even smaller, and the gravitational wave background behind that with even more of a size difference.
- bozhark 3y ago
  Plays right into the white hole theory, interesting
  - bloopernova 3y ago
    As in a white hole is the big bang? That has a kind of poetic symmetry to it, with black holes (big crunches?) being the end, and white holes being the beginning of our particular universe. But our universe has black holes in it. Forgive the layman thinking, but does that mean we're just one of an infinite series of "nested" universes?
    - pelorat 3y ago
      The energy in our universe is not unlimited, so perhaps each black hole spawns a new universe, and each has less and less energy in it. Think about, WHY is there a certain amount of energy in the universe? Why not more or less. Maybe it's just universes all the way down.
- bloopernova 3y ago
  Would the universe in those other 2 older events have been 2 orders of magnitude smaller still? Have there been any estimates made for the sizes in each "event"? Are there even more events further back, or is the next one after gravity the big bang? What a fascinating subject, thank you for expanding my own little universe!
  - ben_w 3y ago
    I'm skim-reading on mobile right now, so here's some more information, but I didn't see anything about how much the universe expanded since 1 second after the big bang, which is the relevant number for the neutrino background: https://en.wikipedia.org/wiki/Cosmic_neutrino_background https://en.wikipedia.org/wiki/Cosmic_neutrino_background https://en.wikipedia.org/wiki/Neutrino_decoupling https://en.wikipedia.org/wiki/Neutrino_decoupling and for gravity: https://en.wikipedia.org/wiki/Gravitational_wave_background https://en.wikipedia.org/wiki/Gravitational_wave_background
devoutsalsa 3y ago
The cosmic microwave background radiation didn’t appear until the universe was about 380,000 years old. https://en.m.wikipedia.org/wiki/Cosmic_microwave_background https://en.m.wikipedia.org/wiki/Cosmic_microwave_background
- oneshtein 3y ago
  So CMB is just 14B years old? Then why we see objects older than CMB? Moreover, why these older than CMB objects appearing in front of CMB?
  - jvanderbot 3y ago
    We dont see galaxies older than CMB.
    - oneshtein 3y ago
      Yep. This is the problem. Why CMB is emitted at the edge of our Universe only? Where are atoms, which produced the CMB?
      - bigbillheck 3y ago
        > Why CMB is emitted at the edge of our Universe only? I thought CMB was emitted everywhere.
        oneshtein 3y ago
        CMB is produced by atoms, right? We see darker/lighter regions in CMB, so we should see a transition somewhere. 300M years is very short period of time, unless everything cooled very very uniformly, which is not the case. Sometimes, somewhere there must be a galaxy past CMB.
        bigbillheck 3y ago
        > a transition somewhere A transition from what to what? > which is not the case. Why not? > Sometimes, somewhere there must be a galaxy past CMB. If there is we'd have to wait for the light from it to get to us, by which time the CMB will have receded further and it would then be in front of the CMB.

__MatrixMan__ 3y ago

I think there's a coherent explanation of the cmb be had there, but it's not the conventional explanation. Under this alternative, the universe cooled to light transparency some time before the moment depicted by the cmb, and anything "further away" than that hugely magnified scene just happened outside of our light cone. That is to say, it's "elsewhere" (a technical term (https://web.phys.ksu.edu/fascination/Interlude1.pdf https://web.phys.ksu.edu/fascination/Interlude1.pdf)). Seems to me that in this alternative, cosmic expansion could be explained as gravitational attraction between elsewhere-matter and matter in our light cone. Imagine there's some argument to be made for why this is not the case, but I don't know it. It would require a bit of explaining re: why that point in history and not some other? - Is it that the maximal distance is constant and that the cmb is subtly changing in ways we havent noticed (as the point of most-distant-past moves forward in time) - Or maybe something caused the speed of light to change at that time, pruning the rest of the universe from our view.