##  [Vaught Conjecture](/vaught-conjecture) 

  ##  [Vaught Conjecture](https://mathlogic.quantumdictionary.io/vaught-conjecture-0) 

  

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**Mathematics & Logic Dictionary**

 







 

 

 

 



 

 

 

 

Definition

An open conjecture in model theory that every complete first‑order theory in a countable language has either countably many or continuum many nonisomorphic countable models; it rules out intermediate cardinalities for the number of countable models.