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Big Bang's Smoking Gun Found
astroengine writes "For the first time, scientists have found direct evidence of the expansion of the universe, a previously theoretical event that took place a fraction of a second after the Big Bang explosion nearly 14 billion years ago. The clue is encoded in the primordial cosmic microwave background radiation that continues to spread through space to this day. Scientists found and measured a key polarization, or orientation, of the microwaves caused by gravitational waves, which are miniature ripples in the fabric of space. Gravitational waves, proposed by Albert Einstein's General Theory of Relativity nearly 100 years ago but never before proven, are believed to have originated in the Big Bang explosion and then been amplified by the universe's inflation. 'Detecting this signal is one of the most important goals in cosmology today,' lead researcher John Kovac, with the Harvard-Smithsonian Center for Astrophysics, said in a statement."
Are you a physicist, or have you seriously studied physics, or do you have a source for that? Because I'm sure I've read numerous times about actual physicists hoping to detect gravity waves from merging black holes.
Yo dawg, I heard you like the Ackermann function, so OH GOD OH GOD OH GOD
Remarkably, the oldest baryons in the* universe are in your head.
* From your reference frame. And only by a nanosecond or so.
"A viable alternate theory is that light gives up some energy while traveling extremely long distances, which shows up as red-shift. Where does the energy go? It could be the source of energy for the CMBR. It could go somewhere else. In any case, as a theory, it explains the red-shift just as well as expansion."
Excellent! Now repeat the rest of the predictions of the Lambda CDM model. Ah, no, you'll have trouble with that one.
"Another viable alternate theory is that the absorption/emission spectra of atoms differs with space/time. Perhaps atoms farther away or longer ago created and absorbed light at lower frequencies, this making older light appear red-shifted by current frequency comparisons. This theory is even harder to test, but just as good at explaining the observations. "
Even better! Now repeat the rest of the predictions of the Lambda CDM model. I think you'll have problems with that one, too.
Actually, I'll give you a bye -- all I want to see is the position of the first peak on the CMB *and* the wavelength of the oscillations in the large-scale structure, with one predicted consistently from the other. Once you've done that, if you can further get out supernovae 1a redshift/distance plots I'll give you extra credit, but since the progentiors aren't fully understood I'll give you a bye on that one, too.
See, the word "viable" has certain caveats. It has to satisfy the observations it's been built to explain *at least* as well as the theory it's replacing. Second, it has to -- self-consistently -- predict further observations that fit *at least* as well as the theory it's replacing. I'm no fan of Lambda CDM but its successes should convince anyone who's actually looked seriously at them that there's something close to reality there, even if ultimately it's a phenomenology close to reality (which it is; I can prove it's phenomenology -- rigorously -- but I can't demonstrate how wrong it actually is, and neither can anyone else at present, but I can at least assert that up until very recent times it's so close as to be indistinguishable and no that I fit all observations, and even very recently it's exceedingly good).