Entropy and Subtle Interactions

Entropy considerations are used to determine the types of subtle interactions (SI), or psi phenomena, that are consistent with the second law of thermodynamics. The analysis is preceded by a short tutorial on entropy and the second law of thermodynamics. For a coherent advanced (retrocausation) signal to exist, it would conflict with the second law in forward time because it would require a reduction in the entropy of background fluctuations from which the wave appeared to condense. The compensating increase in entropy of the source would occur only later. For advanced phenomena that require only a quantum trigger rather than a coherent wave, there is no conflict with the second law. These concepts are generalized to include all SI, even if they are not retrocausal. Examples of allowed SI are described between living beings and (i) other animate systems, (ii.a) electronic random event generators and (ii.b) non-electronic inanimate systems, and also between (iii) one inanimate system and another.