Question: A cosmological “what if ”
Here’s my question:
suppose for the sake of argument, the big bang happened somewhat differently, that it was like a huge mega supernova, and created super-duper massive black hole. A universal black hole. THE black hole of the entire known universe!
slowing down all the stuff that blew away from it.
the stuff coalesced into galaxies which are all still expanding away from each other.
such a scenario would have all the galaxies at different heights in a huge potential well. now…if our galaxy were further up such a potential well, all the light from all the galaxies further down would be red shifted.
also photons emitted from those galaxies would not only come ‘straight’ up the potential well but also would spiral up the potential well.
If our galaxy were near the ‘top’, light from one galaxy would reach us from many directions, all such photons would be red-shifted, and would have taken different lengths of time to reach us because of the many different spiral geodisics they could have taken. In other words, many of the galaxies we see could in fact be the SAME galaxy seen from a different direction in the sky and at vastly different times in its evolution as well as from its different orientations.
pretty much all the galaxies would appear to be receeding from ours (whether they are or not)
furthermore, between our galaxy and the more red-shifted ones further down the well, the space-time would become more and more stretched the further away from our galaxy you’d go.
And therefore it would appear that the expansion of the universe was therefore ‘speeding up’.
Thus explaining the embarassing ‘dark’ energy issue.
In other words, all the distant galaxies might not be ‘spread out’ over the night sky as they appear to be, but instead be all more or less in the same ‘direction’ (downwards), in one and the same huge potential well of “THE” black hole of the entire Universe, that would make a galactic supermassive black hole look like an electron neutrino!
There would be no ‘center’ because any such center would be in all directions, it would therefore be ‘spread out’ as the surface of a sphere.
So maybe therefore, our view of the universe has been ‘inside out’ as it were.
This view seems consistent with general relativity.
How would we know? observationally, how could we tell the difference?
(it sure would explain the ‘dark’ energy /cosmic acceleration issue, plus it’s a lot less absurd)
Answer: I think that your scenario has one basic flaw in that if the giant supernova which led to the “central” black hole did exist, we would observe a “source” or center for the overall expansion of the universe. In fact, what we see are all galaxies (excluding local gravitational interactions between galaxies located near each other) moving away from each other rather than moving away from a common point. You might want to take a look at some of the questions and answers that have been posted to the cosmology section of this blog for further information.