parameters
esiegel | March 21, 2013"Much later, when I discussed the problem with Einstein, he remarked that the introduction of the cosmological term was the biggest blunder he ever made in his life. But this “blunder,” rejected by Einstein, is still sometimes used by cosmologists even today, and the cosmological constant denoted by the Greek letter Λ rears its ugly head again and again and again." -George Gamow, the father of the Big Bang model
The Big Bang -- the prediction that the Universe started from a hot, dense, rapidly expanding state -- tells us where our cold, star-and-galaxy-rich, slowly expanding Universe full of…
esiegel | April 18, 2008Bret Underwood, a friend of mine from my time in Madison, WI, saw my post on String Theory, and took issue with my statement that it wasn't testable. I'm still standing behind what I said, but let's address what Bret has to say.
I donât understand your argument above for why string theory is untestable. In fact, it seems to me you just outlined the best possible case for string theory! What you said above is that if I have a string theory construction of a phenomenon (say, the Standard Model or Inflation), which uses a set of parameters X, and makes some predictions, then I can find another…
esiegel | March 6, 2008The cosmic microwave background is the radiation left over from the big bang. It's very uniform, 2.725 Kelvin everywhere. We're moving with respect to it, so there's a doppler shift, and we see that as a dipole moment in the Temperature. When we subtract that out, we see variations on the order of 30 microKelvins! WMAP is a satellite (Wilkinson Microwave Anisotropy Probe) that measured these anisotropies, and they just released its year 5 data. First off, with the uniform and dipole parts subtracted out, and with the foreground from the galaxy also taken out, here's the map of the microwave…