In Jain cosmology, the universe (loka) is a structured whole, not an infinite empty space. Key points:

• Loka is organized into three broad realms: Urdhva-loka (the upper worlds/heavens), Madhya-loka (the middle world where humans and many beings live), and Adho-loka (the lower worlds/hells).
• The center of the universe is Mount Meru, around which are concentric continents and oceans, with Jambudvipa (the main continent) occupying the central region.
• The size and exact measurements of these parts are described in Jain scriptures, but there is no single universally accepted physical measurement. DifferentDigambara and Śvetāmbara texts give variations in numbers and details.
• Overall, the cosmos is depicted as finite in its architectural description (with a defined layout and regions) rather than infinite in extent, yet the exact numerical dimensions are symbolic and primarily serve to convey spiritual principles rather than a precise map of space.

If you’d like, I can point you to specific Jain texts or stotras that describe the cosmology in detail and explain the differences between Digambara and Śvetāmbara descriptions.