first CORE meeting

Programme

Further participants

• Takako Nemoto
• Iosif Petrakis

Dinner

Abstracts

• Hajime Ishihara, The Hahn-Banach theorem and infima of convex functions
  We review results on the Hahn-Banach theorem and infima of convex functions in constructive mathematics.
• Sam Sanders, The local constructivity of Nonstandard Analysis
  The constructive nature of the praxis of Nonstandard Analysis (NSA) has been observed by many of its practitioners, and is best captured by Osswald’s claim that ‘NSA is locally constructive’. The local constructivity of NSA is the observation that the mathematics performed in the non- standard world of NSA is extremely effective, while jumping between the standard and nonstandard world is extremely non-constructive in general. Following Osswald’s observation, we show how to bring out the effective and constructive content of ‘pure’ NSA, that is theorems of NSA solely formulated with the nonstandard definitions (of continuity, convergence, etc). We will discuss how to obtain effective information from the Loeb measure, inspired by the Lebesgue measure in Reverse Mathematics.