On A Clear
Day
And on a clear day...
On a clear day...
You can see forever...
And ever...
And ever...
And ever more...
So far is forever?
Because the universe is locally flat, Euclidean, we might
think it is globally flat. However it was proposed that universe is hyperbolic
and it only appears flat locally. [1] I
am copying a figure from that article because it shows curved spacetime, ....and because
it is so darn pretty.
Treating spacetime as hyperbolic solves a number of problems, not the least of which is estimating the size of the universe.
A hyperbolic universe has to be expanding after the
Big Bang. Dr. Mabkhout’s article presents equations, based on Einstein’s
equations and a hyperbolic curved spacetime, which is consistent with the age
of the universe. A flat universe has to resort to dark energy and dark matter to
explain the expansion of the universe and the inconsistency between the age and
size of the universe. However if the universe is hyperbolic, without resorting
to dark matter or energy, the implication is that the age of the universe, 14
billion years, is consistent with the size of the universe, 1.3 x1028
cm, 8.6 x 1022 miles, 14 billion light-years. Of course since the universe
its still expanding, check back in a few billion years and there will be a
different answer for forever.
[1]
Mabkhout,
S.A., 2012. The infinite distance horizon and the hyperbolic inflation in the
hyperbolic universe. Phys. Essays, 25(1), p.112.
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