[Alamo-Girl]

Thank you for your question!

Did time exist before the Big Bang ? if not, how then the Big Bang ?

Time cannot precede the big bang for the same reason there is no "south" of the south pole. Time is a transformation of space in relativity (Lorentz Transformation) - it is relative. Hawking proposes an alternative model for the beginning of real time by using imaginary time - basically, the need for an explanation is the loss of information in a black hole or singularity. IOW, how to explain the unreasonable effectiveness of math, the physical constants, etc.

Neverthess, all cosmologies - whether big bang, imaginary time, multi-verse, ekpyrotic, cyclic, multi-worlds - all of them require a beginning. And that is the issue which invariably puts them in the domain of theology, as the Scriptures say "In the beginning, God created ..."

As Jastrow said (paraphrased) when the scientists climb that final mountain they'll be met by a bunch of theologians who have been waiting for them, for centuries.

[TheBigB]

Yeah, but what about Dingell-Norwood, smarty-pants? =)P

[CheezyChesster]

Soooooo, then if Time couldn't exist before the Big Bang. Then we must think of the "Big Bang" in another sense ? perhaps as a reverse implosion of yet another time or Universe. Which of course implies multiple times existing in a singularity. By the way, I haven't kept up much with the latest and greatest lately, but how is research going with creating artificial singularities that can be used to stretch or warp space time ?