“…Definition 1.1 provides a general model for functions found in areas such as mean field games [1], machine learning [4,42], physics [9,17], optimal transportation [11,14,18,24,34], operator theory [15,25,41], statistics [22,43], matrix analysis [23], mathematical programming [28,35], information theory [33,50], inverse problems [39], and economics [49]. Although it appears for instance in [9,33,50], the preperspective ϕ s is of limited use in variational problems due to its lack of lower semicontinuity and convexity.…”