[layer8]

That isn't quite right. The Big Bang is farther than we can look. We can only look as far as the CMB, some 380.000 years after the Big Bang. The timing of the Big Bang instead comes from calculating the density evolution of the universe backwards. Unless you define "look" as "calculate".

[scotty79]

I think 380000 when compared to 13000000000 counts as "nearly outside". Also math is definitely a way of looking even if it can lead you astray when you extrapolate your mathematical model beyond its range of applicability.