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I love the timing of this with the release of a new/old theory that the universe has always existed : http://zeenews.india.com/news/space/no-big-bang-new-theor

• TbobbyZ 12y ago
  I came here to say this. I'm glad you beat me to it!
• wozniacki 12y ago
  Cosmology from quantum potential ( Ahmed Farag Ali, Saurya Das ) It was shown recently that replacing classical geodesics with quantal (Bohmian) trajectories gives rise to a quantum corrected Raychaudhuri equation (QRE). In this article we derive the second order Friedmann equations from the QRE, and show that this also contains a couple of quantum correction terms, the first of which can be interpreted as cosmological constant (and gives a correct estimate of its observed value), while the second as a radiation term in the early universe, which gets rid of the big-bang singularity and predicts an infinite age of our universe. [1] [1] http://arxiv.org/pdf/1404.3093v3.pdf http://arxiv.org/pdf/1404.3093v3.pdf
  • saiya-jin 12y ago
    If universe is older than big bang, why don't we see anything older than that? I mean, there isnt such a drop in visibility of galaxy/bright object that is 5 billion vs 10 bilion years old. So, where are all 30 or more billion year old objects? Maybe there wasn't ultimate singularity in the beginning, but universe is definitely not the same no matter how far you look in the past.
    • ccozan 12y ago
      I think the answer is here [1]. [1] http://en.wikipedia.org/wiki/Observable_universe#Misconceptions_on_its_size http://en.wikipedia.org/wiki/Observable_universe#Misconcepti...
• privong 12y ago
  The theory you link to would likely not have any bearing on the issue of the existence of this supermassive black hole at such a time. Based on my understanding of it, that new theory predicts that the Universe has always existed, by doing away with the singularity prior to inflation ([0] for some information on inflation). But it does not really affect our understanding of what happens post-inflation. The post-inflation period is when quantum fluctuations are amplified by gravity, resulting in the formation of structure[1]. To be a bit more specific, the relevant time interval for this Nature paper is between when dark matter halos began collapsing and when this quasar turned on, not the interval between the start of the Universe until the quasar turned on. However, in the currently-favored cosmology, the "start" of the Universe is followed very rapidly by the onset of structure formation, so the two are effectively the same point in time (at least, for the purposes of supermassive black hole formation and growth). As it relates to this Nature paper, the theory you reference merely separates the "start" of the Universe from the onset of structure formation, so it doesn't affect the relevant time interval for this particular question. > I always new that there was a relationship between black holes and quasars (In/Out) but was unaware that there was an established relationship between specific events. Does anyone have links to this ? It isn't so much a link between specific times as a limit on how quickly you can grow a black hole. The formation of supermassive black holes is fairly uncertain[2], but models generally predict that you start with a black hole that is 1–100 times the mass of the Sun and then grow it by accreting gas. There's a limit to how quickly you can accrete gas[3], so there's a limit to how quickly you can grow the black hole. If you put those two things together, there isn't enough time elapsed between the onset of structure formation and this newly discovered quasar was active, with such a high mass black hole. [0] https://en.wikipedia.org/wiki/Inflation_%28cosmology%29 https://en.wikipedia.org/wiki/Inflation_%28cosmology%29 [1] https://en.wikipedia.org/wiki/Lambda-CDM_model https://en.wikipedia.org/wiki/Lambda-CDM_model [2] https://en.wikipedia.org/wiki/Supermassive_black_hole#Formation https://en.wikipedia.org/wiki/Supermassive_black_hole#Format... [3] https://en.wikipedia.org/wiki/Eddington_luminosity https://en.wikipedia.org/wiki/Eddington_luminosity Edit: modified wording for clarity.
• tempodox 12y ago
  I wouldn't go so far as to say “no big bang”, at least not exactly. Maybe the phenomenon we interpret as an event at a fixed point in the past is actually happening “all the time” (it's hard to use our language correctly when talking about the thing which defines <time> and <space> in the first place). What if background radiation doesn't actually come “from the past” but is what is left after black holes squirt some of the stuff that fell into them all over space & time in shreds (traversing the singularity)? Just an idea. Anyway, I'm only waiting for the first object to be found that is “older” than the big bang :)