The direction of time and Boltzmann's time hypothesis

This work explores Boltzmann's time hypothesis, which associates the perceived direction of time flow with the second law of thermodynamics. We discuss mechanisms that can be responsible for the action of the second law, for directional properties of time and, ultimately, for the perception that past events cause future events. Special attention is paid to possibility of testing these mechanisms in experiments. It is argued that CP-violations known in particle physics may offer such an opportunity. Entropy-based analysis of decoherence and collapse during traditional quantum measurements and a time-symmetric version of Everett's many-worlds interpretation are given in the appendix.