However, an increase in the scope of Soviet political repression, marked by the first show trial, the Shakhty Trial, brought into the focus of Bolsheviks the question whether "bourgeois intelligentsia", including workers of culture and arts, can be loyal and trustworthy.
[1] Soon the concept of socialist realism was established, as the officially approved form of art, an instrument of propaganda, and the main touchstone of ideological censorship.
Certain scientific fields in the Soviet Union were suppressed after being labeled as ideologically suspect.
The suppression of research began during the Stalin era and continued, in softened forms, after his regime.
[4] Leon Trotsky had defended Einstein’s theory of relativity in Soviet intellectual circles but this became an anathema during the Stalin era and was only rehabilitated following the latter’s death.