Question:
Does space go on forever, or does it eventually end? What is the Torah’s view on whether the universe is infinite or finite?
Answer:
This question has occupied both scientists and Torah scholars for centuries.
Historically, many scientists assumed that space was infinite and extended forever in all directions. In the twentieth century, however, new models of the universe emerged. Notably, Einstein discussed the possibility of a universe that is finite yet unbounded, meaning that space has a finite size, but one never encounters an “edge” or a wall. Rather, if one could travel far enough in a straight line, he would theoretically return to where he started, much like a person traveling continuously on the surface of a globe eventually returns to his original location.
Turning to Torah sources, the general picture that emerges from the revealed, philosophical, and mystical sources in Torah literature is that the physical universe is finite and not infinite. Although to our eyes the heavens appear endless, Torah sources describe the created universe as having defined parameters and limits. In greater detail, the Sages, Kabbalists, and early Jewish philosophers describe the physical universe as consisting of a series of celestial spheres, often enumerated as nine spheres. The outermost sphere marks the boundary of the physical cosmos. Beyond that boundary is not another physical region of space, but rather a non-physical reality, a realm of intellect and spirituality that transcends the dimensions of physical existence. [Accordingly, when Torah sources speak of the end of the universe, they do not mean that a traveler would eventually encounter a wall or barrier. Rather, they mean that physical space itself has limits, and beyond those limits lies a mode of existence entirely beyond physical dimensions and therefore beyond human imagination. Just as one cannot visualize a color that has never been seen or a physical object that exists outside all dimensions of space, so too the reality beyond the physical universe is not something that can be represented by the human mind because it belongs to the world of pure intellect and spirituality rather than the world of matter and extension.]
Hence, the above does not mean that the universe ends at a giant wall beyond which one can travel no further. Rather, the concept is closer to a finite yet unbounded reality. Since nothing physical exists outside the created universe, speaking of “going beyond the universe” is itself problematic. One may compare it to asking what lies north of the North Pole. The question assumes a direction that no longer exists beyond a certain point.
Indeed, one of the most difficult concepts for the human mind to grasp is how something can be finite without having a boundary that can be reached. Yet we already encounter similar ideas in other areas. Consider time. If time stretched infinitely into the past, one could ask how the present moment could ever be reached. Torah therefore teaches that time itself had a beginning with creation. Likewise, space, being a created entity, is also understood as possessing limits.
Accordingly, the Torah view is that the universe does not extend with actual infinity. Rather, it is a creation with defined dimensions established by Hashem. While its vastness is beyond human comprehension, it nevertheless remains finite. The fact that we do not perceive an end when looking into the heavens does not prove infinity any more than standing on the ocean proves that the earth has no limits.
Interestingly, this concept bears some resemblance to Einstein’s discussion of a finite yet unbounded universe, in which space is not infinite, yet one never encounters a literal edge. While Einstein’s theory is a scientific model and Torah sources arrive at their conclusions through entirely different means, both reject the simplistic notion that the universe must either be infinite or terminate at a physical wall.
Conclusion:
According to Torah thought, space is a creation and therefore finite. Although the universe appears endless to us, it does not extend with absolute infinity. Its exact structure is beyond our comprehension, but like time itself, it is a created reality with limits established by its Creator.
Sources:
Pardes of Ramak Shaar 6:3; Derech Mitzvosecha Mitzvas Hamanas Elokus Chapter 11; Sefer Hachakira 32; Sefer Haikarim Maamr 2:17; Rambam Hilchos Yesodei Hatorah 3:1; Likkutei Torah Bracha 98a; Sefer Hamamarim 5643 pp. 94-95