Part I

1. A Physical Boundary to Space Requires Something Beyond It

Take any enclosed space, a room, and remove its walls. There is more space beyond. Remove whatever obstruction comes next: another wall, a building, open ground, the atmosphere, a star, a planet. Go around it if it cannot be removed. There is still more space beyond that. Any physical barrier that can be approached, touched, crossed, or even meaningfully described is not a boundary of space itself; it is a structure located within space, and space continues past it. The regress only stops if beyond some final limit there is not empty space but absolute non-being: no extent, no geometry, no location, no physical property of any kind. But absolute non-being cannot function as a physical interface. A boundary is a physically meaningful distinction across which something changes; if one side has no physical status whatsoever, there is no interface there to describe, locate, or interact with. A physical boundary of space is therefore not merely undiscovered. It is not a coherent physical state for space to be in. Infinite, eternal space is not one cosmological option among several; it is the only logically stable one [P5].

Source papers: P5

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