Further to Granville Sewell‘s work on the 2nd Law in an open system, here is Duncan & Semura profound insight into how loss of information is the foundation for the 2nd Law of Thermodynamics. This appears foundational to the understanding and development and testing of origin theories and consequent change in physical and biotic systems. ———————

The key insight here is that when one attempts to derive the second law without any reference to information, a step which can be described as information loss always makes its way into the derivation by some sleight of hand. An information-losing approximation is necessary, and adds essentially new physics into the model which is outside the realm of energy dynamics.

4. Summary of the Perspective

1) Energy and information dynamics are independent but coupled (see Figure 1).

2) The second law of thermodynamic is not reducible purely to mechanics (classical or quantum); it is part of information dynamics. That is, the second law exists because there is a restriction applying to information that is outside of and additional to the laws of classical or quantum mechanics.

3) The foundational principle underlying the second law can then be expressed succinctly in terms of information loss:

“No process can result in a net gain of information.”

In other words, the uncertainty about the detailed state of a system cannot decrease over time – uncertainty increases or stays the same.

The information loss perspective provides a natural framework for incorporating extensions and apparent challenges to the second law. The principle that “no process can result in a net gain of information” appears to be deeper and more universal than standard formulations of the second law.

. . . the information-loss framework offers the possibility of discovering new mechanisms of information storage through the analysis of second law challenges, deepening our understanding both of the second law and of information dynamics.

See full paper: Information Loss as a Foundational Principle for the Second Law of Thermodynamics, T. L. Duncan, J. S. Semura

Foundations of Physics, Foundations of Physics, Volume 37, Issue 12, pp.1767-1773, DOI 10.1007/s10701-007-9159-z

This builds on Duncan & Semura’s first paper:

The Deep Physics Behind the Second Law: Information and Energy As Independent Forms of Bookkeeping, T. Duncan, J. Semura, Entropy 2004, 6, 21-29, arXiv:cond-mat/0501014v1