Good News for Big Bang theory

In article ,
" writes:
When are you going to stop beating around the bush and present
quantitative predictions by which we can definitively test the BB
paradigm, or admit that it is not falsifiable.

The BB model is certainly falsifiable. Blue shifts for distant
objects would do it, to name only the most obvious thing. For
"future measurements" -- if you think those are somehow more
important than existing ones -- a few years ago, we would have
pointed to the power spectrum of microwave background fluctuations,
which WMAP has now measured. Now I think we might point to the
polarization power spectrum. Can anyone provide an update on what
WMAP has seen and what it is likely to see in the rest of its
mission?

--
Steve Willner Phone 617-495-7123
Cambridge, MA 02138 USA
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In article ,
" writes:
When are you going to stop beating around the bush and present
quantitative predictions by which we can definitively test the BB
paradigm, or admit that it is not falsifiable.

Steve Willner pointed out
The BB model is certainly falsifiable. Blue shifts for distant
objects would do it, to name only the most obvious thing. [[...]]

Another example-and-a-half of an observation(s) which would falsify
the BB model would be an in-situ measurement of a CMBR temperature
significantly *less* than the present-day value (2.73K) either in
some distant (& hence old) object, or (via some as-yet-unknown
measurement technique) at some time in our own past.

That is,
(1) By careful spectroscopic observations of some distant astronomical
objects, we can infer the relative occupancies of different energy
levels of certain atoms/molecules, and hence infer properties of
the (CMBR) radiation field which (we infer) excited them.
[See, eg, Srianand, Petitjean & Ledoux, Nature 408, 931 (2000),
"The cosmic microwave background radiation temperature at
a redshift of 2.34".]
The BB model predicts that this temperature must be *higher*
than the present-day CMBR temperature; if the observations were to
come out *lower* I don't see how this could be reconciled with the
BB model.
(2) By laboratory measurements of isotope abundances in Uranium ores,
we infer the operation of a natural nuclear reactor
http://en.wikipedia.org/wiki/Natural...ission_reactor
around 1.5e9 years near Oklo, Gabon. So far as I know the CMBR
temperature at the time didn't significantly affect the Oklo reactor,
so there's no way to use the Oklo data to study the time variation
of the CMBR temperature at our location in the universe.

However, if some (as-yet-undiscovered, or at least unknown-to-me-now)
technique were to be developed to allow this time variation to be
measured, the BB model predicts that the past temperature must be
*higher* than the present-day CMBR temperature; I don't see how a
*lower* measurement could be reconciled with the BB model.

[Just to be clear, the conceptual difference between (1) and (2) is that
(1) is measuring the CMBR temperature in the past at a location in the
universe distant from ours, while (2) is (imagining) measuring the CMBR
temperature in the past at *our* location location in the universe.]

ciao,

--
-- "Jonathan Thornburg -- remove -animal to reply"
Max-Planck-Institut fuer Gravitationsphysik (Albert-Einstein-Institut),
Golm, Germany, "Old Europe" http://www.aei.mpg.de/~jthorn/home.html
"Washing one's hands of the conflict between the powerful and the
powerless means to side with the powerful, not to be neutral."
-- quote by Freire / poster by Oxfam

Steve Willner wrote:
The BB model is certainly falsifiable. Blue shifts for distant
objects would do it, to name only the most obvious thing. For
"future measurements" -- if you think those are somehow more
important than existing ones -- a few years ago, we would have
pointed to the power spectrum of microwave background fluctuations,
which WMAP has now measured. Now I think we might point to the
polarization power spectrum. Can anyone provide an update on what
WMAP has seen and what it is likely to see in the rest of its
mission?

I fear that no matter what the properties of the CMB turn out to be:
anomalous quadrupole or octopole properties, too much power on scale x,
too little power on scale y, strong polarization, weak polarization,
etc., the standard "precision cosmology" model is so plastic that it
will be modified to "fit" the data. After a barely decent interval,
proponents will then say, "See, just what we predicted!".

This is the danger of model-building without definitive tests. It is
virtually impossible to falsify and important new ideas get ignored
because the "standard" model is widely regarded as the only reasonable
path forward.

Robert