Verifiable delay functions (VDF) are functions that take a specified number of sequential steps to be evaluated but can be verified efficiently. In this paper, we show that every VDF is provable in PSPACE and every language in PSPACE admits to a VDF.

翻译：可核实的延迟功能(VDF)是需要评估的顺序步骤数量特定但可以有效核实的职能。 在本文中,我们表明每个VDF都可以在PSPACE中找到,而PSPACE中的每一语言都接受VDF。