open universe

If the open universe we see today is extrapolated
back near the beginning, the ratio of the actual
density of matter in the universe to the critical
density must differ from unity by just a part in 1059.
Any larger deviation would result in a universe
already collapsed on itself or already dissipated.
Inflation failed to achieve its goal when many observations went
against it. To maintain consistency and salvage inflation, the Big
Bang has now introduced two new adjustable parameters: (1) the
cosmological constant, which has a major fine-tuning problem of its
own because theory suggests it ought to be of order 10120, and
observations suggest a value less than 1; and (2) “quintessence” or
“dark energy.” [35,36] This latter theoretical substance solves the
fine-tuning problem by introducing invisible, undetectable energy
sprinkled at will as needed throughout the universe to keep
consistency between theory and observations. It can therefore be
accurately described as “the ultimate fudge factor.”
* * * * *
Anyone doubting the Big Bang in its present form (which includes
most astronomy-interested people outside the field of astronomy,
according to one recent survey) would have good cause for that
opinion and could easily defend such a position. This is a
fundamentally different matter than proving the Big Bang did not
happen, which would be proving a negative—something that is
normally impossible. (E.g., we cannot prove that Santa Claus does not

exist.) The Big Bang, much like the Santa Claus hypothesis, no longer
makes testable predictions wherein proponents agree that a failure
would falsify the hypothesis. Instead, the theory is continually
amended to account for all new, unexpected discoveries. Indeed,
many young scientists now think of this as a normal process in
science! They forget or were never taught that a model has value only
when it can predict new things that differentiate the model from
chance and from other models before the new things are discovered.
Explanations of new things are supposed to flow from the basic
theory itself with at most an adjustable parameter or two, and not
from add-on bits of new theory.
Of course, the literature also contains the occasional review paper
in support of the Big Bang. [37] But these generally don’t count any
of the prediction failures or surprises as theory failures as long as
some ad hoc theory might explain them. And the “prediction
successes” in almost every case do not distinguish the Big Bang from
any of the four leading competitor models: Quasi-Steady-State
[16,38], Plasma Cosmology [18], Meta Model [3], and Variable-Mass
Cosmology [20].

For the most part, these four alternative cosmologies are ignored
by astronomers. However, one web site by Ned Wright does try to
advance counterarguments in defense of the Big Bang. [39] But his
counterarguments are mostly old objections long since defeated.