Table 1 summarizes the current estimates of
m from the various
methods of measurement. In general, the methods based on virialized objects
favor low values, while the global measures (with the exception of
the age argument) and the analysis of large-scale structure and flows
tend towards higher values.
The estimates that indicate very low values (~ 0.1 - 0.2)
have plausible loopholes. On the other hand, none of the estimates that favor
high m values
actually requires that m
is as large as unity.
It thus seems that a tentative consensus can be reached at a (not very
elegant) value of about
m
0.5.
This was reflected in the debate on formation scenarios by the fact that
the competing CDM models were the Einstein deSitter
m = 1
``standard'' CDM (with n ~ 0.9) or Hot+CDM, versus the Open CDM
and Flat (
) CDM models with
m
0.4.
Not too long ago these
low-m models used to
be associated with
m ~ 0.1 - 0.2. It
seems that progress is being made towards
convergence.
The activity on many fronts of this field promises
that we will know more in the near future.
We hope that the above discussion will be of help in the effort to
reconcile the various estimates with a unique value of
m.
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