Currently, we don't know if we live in an infinite or finite universe. But let's say, for the sake of argument, that we do live in an infinite universe. So that if we would have a space ship with an infinite amount of fuel, we could keep on going forever. Infinity is something the human brain can't really comprehend, because from the start of our lives we experience everything to have a beginning and ending, even life... So to think there is something, or in this case everything, that just keeps on going for ever, is really mind bending.
But if our universe is indeed infinite, would this mean that size of any kind becomes purely fictional if we look at the bigger picture? If we look from our own perspective measuring things is no problem, since we are finite in length, width and depth, we can perfectly measure something from our perspective, and even a-dress a number to it. This number will give us an approximation of how big or small an object is.
What if we take a grain of sand on the beach? We could perfectly measure this compared to the size of the beach we found the grain in. But what if we keep on expanding this beach, the grain of sand would get relatively smaller and smaller. So now we take our universe that is in this case infinite, and we compare the Earth to it. The size of the Earth would we infinitely small, compared to an infinite universe. Because the bigger a space gets, the relatively smaller objects within it get.
Like if there where to be a person with an infinite amount of money, (not taking the economical catastrophe of this in to account), from his perspective everything would be free. Because when he would spent a certain amount of money, it wouldn’t be noticeable on his balance.
Does this mean an infinite universe would cancel out size of any sort? I think it does. If we could look from the universe’s perspective, the word 'size' wouldn't exist in our dictionary.