How many times in your life have you used the term 'infinity' as if we know its meaning? Even thought it exists only by the theories of science, math, the spiritual, the mystical, perception and by our simplistic references to it, to this day man knows no physical condition that is infinite.
The energies of a Hydrogen bomb or those massive particle accelerators that force sub-atomic collisions, for the universal scale analysis of scientists, can hardly be considered infinite especially since we don't have the equipment to measure energy beyond the currently recorded lowest state of its atomic decay. Massive collisions of star systems, galactic explosions, implosions, merging galaxies and black holes are very large indeed, but they can hardly be called infinite.
By definition, infinity must embrace everything that we know and everything we don't know. Beyond the finite of our universal realm, forever enveloping everything and anything in its multi dimensional path, nothing can possibly disturb infinities' voracious perpetual reach. It must, by definition, be the perfected state capable of sustaining its' ever present form. The Infinite is an endless energy state, it is borderless, has no boundaries and no dimensions yet, by its very definition, it must, simultaneously, be infinitely small and infinitely big.
Since we do not know of anything that is infinite, only our imaginations can provide the fodder to feed our intellectual probes, but most, if not all, agree that somewhere The Infinite state exists.
If we are 'finite' physical beings or if the universe is some figment of some single or collective imagination, or spiritual state, then one must logically conclude something pre-exists either state in order that it could be brought into existence. If one assumes our presence in this world is imaginary or spiritual, then something must exist in a spiritual sense that gives rise to our common ability to imagine our own existence. Either way something before our universe must have existed.
As more is revealed through the evolving technologies of science, the exhaustive interests of physicists, mathematicians and chemists moves beyond the boundaries of our universe to the serious questions that lie outside the realm of the known. Questions like these place science on a path that converges it with mystical and spiritual for as it reaches the limit of practical proof it begins to deal with the unknown, which has been the exclusive domain of religion and the spiritual. Therefore, to intellectually analyze our existence we must first answer; from where or what do we emerge?
It's important to understand that your physical presence in space has an effect on all surrounding space; Einstein defined this in his Theory of Relativity.
Imagine our entire universe to be nothing more than the internal space of a tiny atomic sized dot on a celestial scale much, much bigger than anything you can possibly perceive. Using this analogy, lets say that everything our astronomers have seen and everything we know is contained within that dot, a small physical space of some greater universal condition, which is of a massively giant scale, much greater than that of our universe. Our universe is then a tiny subset of something much bigger, even though we presently perceive it as being gigantic. How many iterations of this analogy need to be extended before the ultimate question arises ; what came before all that we can possibly contemplate?
Inevitably one must conclude that something existed before the beginning of man's definition of finite time, which science suggests took place some 13-15 billion years ago. Sometime, somewhere, someplace or no-place before this point one can only conceive the infinite and mans emergence from it.
 Duties Of The Heart "The Unity Of God" Ch. 5 pg 81