[FOM] Banach spaces: A more precise question
Timothy Y. Chow
tchow at alum.mit.edu
Tue Feb 17 16:20:18 EST 2009
> This is a followup to my previous vague inquiry about Banach spaces.
> Can the existence of Tsirelson's space be proved in RCA_0?
Because of interest in this question, Gowers has started a new blog entry
Let me mention that one reason to suspect that the existence of
Tsirelson's space may not be provable in RCA_0 is that according to
Gowers, the usual definition involves an induction over a set of finite
trees, which has a bit of the feeling of the weak Koenig lemma to it.
This could turn into quite an interesting application of reverse
mathematics if it pans out.
More information about the FOM