wrote:
Phillip Helbig---remove CLOTHES to reply wrote:

Prediction, prior observation, prediction, assumption later verified by
observation.

By my accounting this list should read:

1. Background Radiation: prediction, but initially off by about 400%
and had to be adjusted to come into agreement with observations.

Your 400% seems way off -- Alpher and Herman's 1948 prediction was "about 5K."
Furthermore, you're not quite asking the right question. CMBR temperature
varies with time, so to predict the value "now" you need to know when "now"
is, relative to, say, primordial nucleosynthesis. Alpher and Herman used
(baryonic) matter density as a proxy for this, and got the correct relation;
their error in the exact value came from an imprecise knowledge of the
present matter density.

Remember also that the prediction was not just a temperature, but a spectrum.
Black body spectra are hard to make (since temperatures of different sources
get different red shifts); the observation of not only the temperature but
the spectrum is a very strong confirmation.

2. Global expansion: agreed, this was prior knowledge.

3. Abundances of light elements: definitely not predicted! We had good
approximate abundances prior to any BB paradigm.

Joseph Lazio has addressed this.

You shouls also add a number of other predictions:

-- red shift dependence of CMBR temperature (for observations, well after the
predictions, see Battistelli et al., astro-ph/0208027; Srianand et al.,
astro-ph/0012222; Molaro et al., astro-ph/0111589)

-- Tolman surface brightness test (predicted by Tolman in 1930; observed by
Lubin and Sandage, astro-ph/0106566)

-- time dilation of supernova light curves (predicted by Wilson, Ap. J. 90
(1939) 634; for observations, see Goldhaber et al., astro-ph/0104382)

-- three (and no more) light neutrinos (predicted by Yang et al., Ap. J. 227
(1979) 697; confirmed in accelerator experiments later -- see, e.g., ALEPH
Collaboration, Phys. Lett. B235 (1990) 399)

Steve Carlip