One of the most troublesome questions within the branch of cosmology has always been regarding the limits of the universe. Do the cosmos have an edge? If yes, then what lies beyond it? 

As it happens, there is a thought-provoking riddle that was celebrated throughout the middle ages; What happens when a spear is flung across the cosmic edge? This intriguing inquiry can be traced back to Archytas of Tarentum, The phytagorean philosopher-scientist. The spear of Archytas is considered to be the shatterer of universes. 

Suppose the universe did indeed have a limit… a boundary… an edge. Now suppose, somehow a certain individual made his or her way to the very uttermost end of the universe and hurled a sphere towards it. Would the spear rebound? Would it continue its path? Or would it disappear? 

In the middle ages, Simplicius gave a mind-blowing answer to this riddle; “If i am at the extremity of the heaven of the fixed stars, can i stretch outwards my hand or staff? It is absurd to suppose that i could not; and if i can, what is outside must be either body or space. We may then in the same way get to the outside of that again, and so on; and if there is always a new place to which the staff may be held out, this clearly involves extension without limit.” 

Thus, to claim that the universe has a boundary is no different than it being infinite.