Retrocausation and the Thermodynamic Arrow of Time

Abstract

The thermodynamic arrow of time is directed by the second law of thermodynamics. In the last ten years, over two dozen theoretical challenges to the second law, many of them laboratory testable, have cast serious doubt on the law’s continued universality. In this paper we review a representative challenge and consider the possibility that the thermodynamic arrow might be reversed on local or global scales. Experiments are proposed to test the connections between retrocausation and a reversed thermodynamic arrow.