Conditions for a Dynkin system to be a sigma-algebra

This page is intended to list different conditions for a Dynkin system (also called a $d$-system) to be a $\sigma$-algebra

Conditions

• A Dynkin system, $\mathcal{D}$ is a $\sigma$-algebra if and only if it is $\cap$-closed (which is to say it is also a $p$-system)

See also

• Conditions for a generated Dynkin system to be a $\sigma$-algebra