The influence of Abraham Robinson's theory of nonstandard analysis has been felt in a number of fields.
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"Radically elementary probability theory" of Edward Nelson combines the discrete and the continuous theory through the infinitesimal approach. Random infinitesimal steps can be used to model Brownian motion, obviating the need for cumbersome measuretheoretic developments.
Economists have used nonstandard analysis to model markets with large numbers of agents.
The article by Michèle Artigue cited below concerns the teaching of analysis. Artigue devotes one page to "NSA and its weak impact on education", page 172. She writes:
Artigue continues specifically with reference to the calculus textbook:
Google Scholar lists 974 cites for "Nonstandard analysis". Reproduced below are a few of the most influential publications involved.
