olemus
võimalike olekute hulk
= the set of all possible states

ülevaateid
https://en.wikipedia.org/wiki/State_space

https://en.wikipedia.org/wiki/State-space_representation

http://www.scholarpedia.org/article/State_space_model

https://lpsa.swarthmore.edu/Representations/SysRepSS.html

https://cel.archives-ouvertes.fr/hal-02987750v2/document