Today I have been travelling across the night sky with Google Earth a bit. As always I'm surprised about how inspiring the cosmos is for thinking about physics. But I've always been quite skeptical about the big bang theory. Nowadays we're unable to simulate even a single hadron. And the observation of the sun seems to be a constant source of surprise about it's inner workings. Yet people claim in detail about how the big bang took place and what happened when. I don't say the big bang is wrong because I'm not an expert in cosmology. But isnt't it a rather foolhardy extrapolation ? I have no philosophical (or whatever psychologically or religiously motivated) problem with a big bang apart from finding it a little strange that there should have been a singular event where such a huge amount of energy has been accidentally created from the vacuum. But if it was that way, well, okay. What I do have a problem with is the assumption that the laws of physics have been the same for 13 billion years and/or over a distance of 13 billion lightyears. Who can say that ? Probably masses and coupling constants are just a matter of boundary conditions. If I were to bet my son's life on the big bang, I would never ever do so. So what makes you cosmologists so sure about that thing ?