Related Experiment Video
Updated: Jul 18, 2025

Real-Time Proxy-Control of Re-Parameterized Peripheral Signals using a Close-Loop Interface
Published on: May 8, 2021
Second Law and Its Amendment: The Axiom of No-Reversible Directions Revisited
1Institut für Theoretische Physik, Technische Universität Berlin, Hardenbergstr, 36, D-10623 Berlin, Germany.
Abstract:
A toy model is used to describe the following steps to achieve the no-reversible-direction axiom in a tutorial manner: (i) choose a state space results in the balance equations on state space which are linear in the process directions, (ii) avoid a reversible process direction that cannot be generated via a combination of non-reversible ones, (iii) process directions that are in the kernel of the balance equations and do not enter the entropy production. The Coleman-Mizel formulation of the second law and the Liu relations follow immediately.
Related Concept Videos
Woodward–Hoffmann Selection Rules and Microscopic Reversibility
Reversible and Irreversible Processes
Entropy Change in Reversible Processes
The statement can be further generalized to prove that entropy is a state function. Take a cyclic process between any two points on a p-V diagram.
Statements of the Second Law of Thermodynamics
First Law: Particles in One-dimensional Equilibrium
First Law: Particles in Two-dimensional Equilibrium
Newton's first law tells us about...

