Speaker: 

Nam Trang

Institution: 

University of North Texas, Denton

Time: 

Tuesday, June 2, 2026 - 3:00pm to 3:50pm

Host: 

Location: 

RH 340P

The ABCD hypothesis, formulated by Chan, Jackson and Trang, is the conjunction of $ZF$ and the statement: (*) given four infinite cardinals $A, B, C, D$, then $|A^B| \leq |C^D|$ if and only if $A\leq C$ and $B\leq D$. Recently W. Chan shows that $AD^+$ implies (*) holds below $\Theta$. We sketch a scenario to improve this result and show the full ABCD hypothesis is consistent. This is not a complete proof as it relies on conjectures about the structure theory of Nairian models but presents the most plausible path towards the consistency proof.