Questioning Infinity

The big bang theory,universal inflation theory,backround radiation lead to the scientific conclusion that the universe as we know it is finite.
And if we consider the universe finite,then other conditions of infinity fail.
Infinitly fast would break through the fabric of the universe,infinitly small would fall through it,infinitly large would surpass it,and many others.
Infinity may be theoreticaly justifiable,but how do we logically justify a concept that has conditions that may be contrary to the universe as we know it?