Tagged Questions
3
votes
0answers
35 views
algebraic or homotopical proof for Kakutani fixed point theorem
As Kakutani fixed point theorem is a genral case of Brouwer fixed point theorem, and one can read the proof from homotopy theory books. I wonder if there is any proof for the Kakutani using homotopy ...
1
vote
2answers
124 views
Finding the fixed point of a function
Let $p:A \times B \to \mathbb{R}$ be a nonnegative real-valued function on $A \times B$,
where $A$ and $B$ are arbitrary set.
Assume $f:A \to B$ and $g:B \to A$ are such that
\begin{align*}
f(a) ...
8
votes
1answer
296 views
Common knowledge as a fixed point
I read on a wikipedia page that from the modal logic formalization CK can be formulated as a fixed point. If it also holds for the set theory formalization? If it does, where I can find about it?
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