Comment by ndsipa_pomu
Comment by ndsipa_pomu 3 days ago
I recall seeing something (likely a youtube video on cosmology) that suggested that the Big Bang would be the white hole horizon (i.e. a singularity in out past) and that does make some kind of sense as it'd be impossible to go inside the Big Bang. I recall there being some good reasons as to why that's not believed to be the case though and also why the visible universe doesn't have an event horizon.
> the Big Bang would be the white hole horizon (i.e. a singularity in out past)
The white hole horizon is not the same thing as the white hole singularity. The "Big Bang" as an initial singularity in our universe (which is not actually the correct usage of the term "Big Bang", but that's a whole other discussion) would be the white hole singularity, not the horizon.
Note also that in a white hole model of our universe, we would be inside the white hole horizon, not outside it.