The 2nd law of thermodynamics states that in any closed system, entropy never decreases. The two apparent loopholes in this law, that entropy can decrease in open systems and can remain the same in either type of system are not of interest here.
Entropy is equivalent to both information and disorder. Attempts to define information as negative entropy are wrong, as is defining information as order. The more orderly the arrangement, no matter what the context, the less information that can be embodied in the arrangement. Information is a measure of improbability, as is entropy. The term “entropy” is often abused to mean not the information embodied in a specific arrangement, but the class of all possible arrangements which look similar from a distance, or averaged together by coarse measurements. Nevertheless, all real cups of hot tea, even those indistinguishable to any macroscopic measurements and composed of absolutely identical constituent molecules, are at the molecular level entirely different in their components' positions and velocities, just as much as two identical pieces of paper with identical amounts of ink, one showing a humorous picture of a cat and the other a budget summary for the Wolverhampton waterworks.
Every event at the molecular (or any other) level which has lasting consequences creates information. That information is almost always encoded in heat. It gradually diffuses, becoming more and more entangled with other bits of information so that one would have to know about more and more to have any hope of determining the original causes behind the motions. Creation and transmission of information require no energy dissipation in general, but erasing information does. The entropy of the information “erased” is not really destroyed, but moved to the outside environment, in the same way as heat is moved to the outside of a refrigerator. Even dropping information into a black hole does not destroy it, but instead it is very gradually re-emitted in a scrambled form as the black hole evaporates All molecular events with consequences that are in principle distinguishable from some other hypothetical course of events leave a permanent but increasingly scrambled record in thermal motions and thermal radiation. This permanent record is the physical substrate for what has been called the “Akashic Records”. There is a potential for long-range correlations to emerge in the detailed patterns of thermal motion which in turn could lead to macroscopic correlations of pattern through a type of chaotic sensitivity to initial conditions which leads not just to variations in the location of systems on a given attractor, but to correlations of the type of attractor. [Perhaps, but I now think a sort of consistency filter arising from quantum entanglements is a more likely mechanism.]
Fourier is now best-known for his “Fourier series” which allow representing anything as a sum of sinusoidal waves of varying frequencies, amplitudes, and phases which is the basis of essentially all digital audio-visual techniques, but during his life he was known best for his work on heat diffusion. It turns out that the equations for heat diffusion are exactly the same as for quantum mechanics, except that heat diffuses in euclidean time while relativistic quantum mechanics demands a Minkowski space, meaning that time has a square opposite in sign to the squares of the spatial dimensions. The two can be converted by using “imaginary time”, that is, time multiplied by the square root of -1, i. (Or some other entity that squares to -1, of which it turns out there are several in Geometric Algebra / real-valued Clifford Algebras.) This procedure known as a “Wick rotation” converts the Schrodinger equation to the Boltzman equation. This only makes sense for massive particles – for light-like particles, time has no independent meaning apart from the distance traveled, time is the hypotenuse in the Pythagorean theorem. (x2 + y2 + z2 = t2) (There are experimental results indicating that massive particles, or at least electrons, have no real mass but move in light-speed helices which give them the appearance of having mass. This is David Hestenes' Zitterbewegung interpretation of QM.)
The relation between the eternal time of the thermal record and the Minkowski time of everyday experience is thus a Wick rotation.