This was one of my earliest childhood conundrums, and I am still not much clearer on it; what happens at the largest and smallest scales of space or space time? The infinite number of Russian dolls problem.. How do we deal with the infinite? (or if we take Guth's 10^32 times the size of the observable universe what could lie just beyond?) Similarly how do we deal with infinitesimal distances? Quantized space? Or does space cease to exist? If we do not know the answers to these questions yet (or never expect to) that is ok.