In everyday life we take the meaning of infinity to be anything which we perceive in endless amount like space, energy etc. However the meaning of infinity according to our scriptures is a bit different and in strict terms even space is not infinite according to shruti. In chandogya upanishad infinity is described in following words by venerable sage sanatakumara ji. The questioner is narad muni ji. "The infinite is bliss. There is no bliss in anything finite. Only the Infinite is bliss. One must desire to understand the Infinite." "Venerable Sir, I desire to understand the Infinite." (chandogya upanishad VII-xxiii-1) "Where one sees nothing else, hears nothing else, understands nothing else—that is the Infinite. Where one sees something else, hears something else, understands something else—that is the finite. The Infinite is immortal, the finite mortal." (chandogya upanishad VII-xxiv-1) so the great sage sanatakumara ji clearly tells infinity is something where everything is same, everything is part-less, this verse actually also tells us that even panchbhutas are not infinite and they disappear once duality disappears. For exampe space cannot be called as infinite, because in space are scattered millions of galaxies and stars, so it is not a infinite entity. Only brahm is infinite.