Space and time are relative. Most think that time will continue forever. That means that space will grow as well. Therefore the universe will comtinue to expand forever. According to my secret theory (A=B) the universe will continue expanding forever and after "time" speed up. Time, therefore...
To say that "nothing" can not exist would be audacious because you would be refer referring "nothing" as to something that is more that a concept. To be concise, "nothing" is neither existent nor non-existent.
If you have two particles that are even billions of light years away from each other, is there any gravitational pull between then? (Considering the possibility that there is nothing else in the universe)
If you were to create a seemingly perfect circle on your computer and then zoom in on it, wouldn't it have line segments rather than all curves? Of course, with the computer it is a matter of pixels. But what about in real life?