Computing with many spaces: Generalizing projections for the digital geohumanities and GIScience.

The digital geohumanities-and geographic computation generally-have advanced greatly by representing phenomena within geographic coordinate systems. More specifically, most visualizations and analyses only proceed once data are rendered into a single coordinate system via geolocation and one or more projections. But does it follow that geographic computation should require all phenomena to be represented in Euclidean or spherical geometry in a singular, absolute, Newtonian space? We suggest an approach to pluralizing the spaces available to geographic computation. We both supplement the technical architecture for projections and subtly reframe the purpose and meaning of projections. What we term numerical, generalized projections thereby become more central to GISystems. We suggest how existing libraries might be modified with minimal disruption (taking the widespread and foundational proj.4 library as example). We also envision modifications to existing OGC technical specifications for projections and coordinate systems. Finally, in conversation with the interpretative practice and nuanced spatialities of the digital geohumanities and critical geography, we further extend generalized projections to encompass spatial multiplicity, fragmented spaces, wormholes, and an expanded role for interruptions. This will facilitate: 1) interpretative approaches to scholarship and diverse constructions of space common in the humanities; 2) computational engagement with the ontological and epistemological commitments to relational space of critical human geography; and 3) scientific efforts to understand complex systems in the spaces and times that emerge from those systems' dynamics, revisiting a desire common in early quantitative geography; and 4) the desire for a broad basis of understanding geographic information in GIScience.