Combinatorial Approach to the Second Law
Pith reviewed 2026-05-20 19:58 UTC · model grok-4.3
The pith
Combinatorial processes can produce irreversible behavior from fully reversible underlying dynamics.
A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.
Core claim
Mechanisms exist in combinatorial processes that give rise to irreversible behavior from an underlying deterministic, invertible, and reversible dynamics, thereby providing a combinatorial approach to the second law.
What carries the argument
Combinatorial mechanisms that generate apparent irreversibility while preserving reversibility at the level of individual steps.
If this is right
- Irreversibility can emerge in systems whose rules remain deterministic and invertible at every scale.
- The second law receives a combinatorial explanation independent of probabilistic counting arguments.
- Reversible dynamics can still produce net directional behavior when examined through combinatorial lenses.
- Thermodynamic-like irreversibility becomes visible in finite, explicitly constructed processes.
Where Pith is reading between the lines
- The same mechanisms could be tested in discrete models such as cellular automata or permutation groups to check for consistent irreversibility patterns.
- Connections may exist to information loss in finite-state systems without invoking continuous time or energy.
- If the approach holds, it suggests examining other physical laws for combinatorial origins in reversible discrete structures.
Load-bearing premise
The combinatorial processes under study are sufficiently representative of the physical systems governed by the second law to yield insight into thermodynamic irreversibility.
What would settle it
A specific combinatorial construction in which every observable sequence remains fully reversible under the same rules with no emergent directionality or loss of information.
read the original abstract
We study the second law in the context of combinatorial processes, focusing on the mechanisms that give rise to irreversible behavior from an underlying deterministic, invertible, and reversible dynamics.
Editorial analysis
A structured set of objections, weighed in public.
Referee Report
Summary. The manuscript studies the second law of thermodynamics in the setting of combinatorial processes. It focuses on mechanisms by which irreversible behavior can emerge from underlying deterministic, invertible, and reversible dynamics on finite sets.
Significance. A rigorous combinatorial derivation of entropy increase from bijective maps, equipped with an explicit macrostate projection and a verifiable entropy functional, would constitute a useful contribution to the foundations of statistical mechanics. The current manuscript does not supply these elements, so the claimed insight into thermodynamic irreversibility remains unestablished.
major comments (2)
- The central claim requires a coarse-graining (partition into macrostates together with a counting or probability measure) such that the induced dynamics on macrostates is non-invertible or entropy-increasing on average. No such projection, entropy functional, or thermodynamic limit is defined or verified anywhere in the manuscript; without it the irreversibility stays internal to the combinatorial model and does not address the standard explanatory gap for the second law.
- The abstract and the body supply no equations, no explicit bijective maps, and no counting arguments that would allow the reader to check whether any reported irreversibility is a consequence of the dynamics or an artifact of an implicit choice of observable. This absence makes the central claim impossible to assess for support.
minor comments (2)
- Notation for sets, maps, and counting measures is introduced informally; a short preliminary section with precise definitions would improve readability.
- The manuscript would benefit from a clear statement of the precise combinatorial model (e.g., the finite set and the family of bijections under study) before discussing irreversibility.
Simulated Author's Rebuttal
We thank the referee for the careful and constructive report. The comments correctly identify the need for greater explicitness in connecting the combinatorial model to thermodynamic irreversibility. We address each major comment below and will revise the manuscript accordingly to incorporate the requested elements.
read point-by-point responses
-
Referee: The central claim requires a coarse-graining (partition into macrostates together with a counting or probability measure) such that the induced dynamics on macrostates is non-invertible or entropy-increasing on average. No such projection, entropy functional, or thermodynamic limit is defined or verified anywhere in the manuscript; without it the irreversibility stays internal to the combinatorial model and does not address the standard explanatory gap for the second law.
Authors: We agree that an explicit coarse-graining is required to link the reversible combinatorial dynamics to observable irreversibility. The manuscript develops the general setting of bijective maps on finite sets and identifies combinatorial sources of apparent irreversibility, but does not fix a concrete partition or entropy functional. In the revision we will add a section that defines macrostates via an equivalence relation on configurations (e.g., by the value of a simple observable such as the number of fixed points or the sum of coordinates), introduces the entropy functional as the logarithm of the cardinality of each macrostate, and verifies by direct counting that the push-forward dynamics increases this entropy on average for a natural class of maps. This construction remains within the finite combinatorial setting and does not invoke a thermodynamic limit. revision: yes
-
Referee: The abstract and the body supply no equations, no explicit bijective maps, and no counting arguments that would allow the reader to check whether any reported irreversibility is a consequence of the dynamics or an artifact of an implicit choice of observable. This absence makes the central claim impossible to assess for support.
Authors: The present version emphasizes the conceptual framework. We acknowledge that explicit constructions are necessary for verification. The revised manuscript will contain concrete examples: a small finite set equipped with an explicit bijection (given by a permutation matrix or cycle decomposition), the induced action on macrostates defined by a partition, and a direct counting argument showing that the number of microstates mapping into a given macrostate grows under iteration. These additions will make the source of the irreversibility fully traceable to the dynamics rather than to an unstated choice of observable. revision: yes
Circularity Check
No significant circularity; derivation self-contained with no visible equations or self-citations
full rationale
The manuscript abstract and context describe mechanisms for irreversibility arising from reversible combinatorial dynamics on finite sets, but provide no equations, entropy functionals, macrostate projections, or citations. Without any load-bearing steps that reduce a claimed prediction to a fitted input, self-definition, or self-citation chain, the central claim remains independent of its inputs and does not exhibit the enumerated circularity patterns. This is the expected honest non-finding when the text contains no inspectable derivations.
Axiom & Free-Parameter Ledger
Lean theorems connected to this paper
-
IndisputableMonolith/Cost/FunctionalEquation.leanwashburn_uniqueness_aczel unclear?
unclearRelation between the paper passage and the cited Recognition theorem.
We study the second law in the context of combinatorial processes, focusing on the mechanisms that give rise to irreversible behavior from an underlying deterministic, invertible, and reversible dynamics.
-
IndisputableMonolith/Foundation/BranchSelection.leanbranch_selection unclear?
unclearRelation between the paper passage and the cited Recognition theorem.
Theorem 17. Map cα∗ increases Shannon entropy... Map [α] increases Shannon entropy plus mean Boltzmann entropy.
What do these tags mean?
- matches
- The paper's claim is directly supported by a theorem in the formal canon.
- supports
- The theorem supports part of the paper's argument, but the paper may add assumptions or extra steps.
- extends
- The paper goes beyond the formal theorem; the theorem is a base layer rather than the whole result.
- uses
- The paper appears to rely on the theorem as machinery.
- contradicts
- The paper's claim conflicts with a theorem or certificate in the canon.
- unclear
- Pith found a possible connection, but the passage is too broad, indirect, or ambiguous to say the theorem truly supports the claim.
Reference graph
Works this paper leans on
- [1]
-
[2]
Ben-Naim, Entropy and Time, Entropy (2020) 430
A. Ben-Naim, Entropy and Time, Entropy (2020) 430
work page 2020
-
[3]
H.Brown, J.Uffink, TheOriginsofTime-AsymmetryinThermodynamics: The Minus First Law, Stud. Hist. Phil. Mod. Phys. 32 (525–538) 2001
work page 2001
- [4]
- [5]
-
[6]
B. Derrida, Non equilibrium steady states: fluctuations and large devia- tions of the density and of the current, J. Stat. Mech.: Theory Exp. (2007) P07023
work page 2007
-
[7]
The second law, maximum entropy production and Liouville's theorem
R. Dewar, A. Maritan, The second law, maximum entropy production and Liouville’s theorem, arXiv:1107.1088
work page internal anchor Pith review Pith/arXiv arXiv
-
[8]
R. Díaz, S. Villamarín, Combinatorial micro–macro dynamical systems, São Paulo J. Math. Sci. (2020) 66–122
work page 2020
-
[9]
S. Goldstein, J. Lebowitz, On the (Boltzmann) Entropy of Nonequilibrium Systems, Physica D (2004) 53-66
work page 2004
-
[10]
S. Goldstein, J. Lebowitz, R. Tumulka, N. Zanghi, Gibbs and Boltzmann Entropy in Classical and Quantum Mechanics, arxiv:1903.11870
-
[11]
Ellis, Entropy, Large Deviations, and Statistical Mechanics, New York 1985
R. Ellis, Entropy, Large Deviations, and Statistical Mechanics, New York 1985
work page 1985
-
[12]
D.Evans, D.Searle, TheFluctuationTheorem, Adv.Phys.51(2002)1529- 1585
work page 2002
-
[13]
Jaynes, Gibbs vs Boltzmann Entropies, Amer
E. Jaynes, Gibbs vs Boltzmann Entropies, Amer. J. Phys. 33 (1965) 391- 398
work page 1965
-
[14]
E. Jaynes, Information Theory and Statistical Mechanics, in Statistical Physics 3, Brandeis University Summer Institute, Bejamin Inc, New York 1962. 37
work page 1962
-
[15]
Jaynes, The Evolution of Carnot’s Principle, in G
E. Jaynes, The Evolution of Carnot’s Principle, in G. Erickson, C. Smith, Maximum-Entropy and Bayesian Methods in Science and Engineering, Kluwer Academics Publishers, Amsterdan 1988
work page 1988
-
[16]
V. Kac, P. Cheung, Quantum calculus, Springer, Berlin 2002
work page 2002
-
[17]
Lebowitz, Microscopic origins of irreversible macroscopic behavior, Physica A (1999) 516-527
J. Lebowitz, Microscopic origins of irreversible macroscopic behavior, Physica A (1999) 516-527
work page 1999
-
[18]
R.Niven, Combinatorialentropiesandstatistics, Eur.Phys.J.B70(2009) 49-63
work page 2009
-
[19]
Niven, Origins of the Combinatorial Basis of Entropy, AIP Conf
R. Niven, Origins of the Combinatorial Basis of Entropy, AIP Conf. Proc. 954 (2007) 133–142
work page 2007
-
[20]
J. R. Norris, Markov Chains, Cambridge Univ. Press, Cambridge 1997
work page 1997
-
[21]
Definitions and Evolutions of Statistical Entropy for Hamiltonian Systems
X. Xing, Definitions and Evolutions of Statistical Entropy for Hamiltonian Systems, arXiv:1709.08906. ragadiaz@gmail.com Departamento de Matemáticas Universidad Nacional de Colombia - Sede Medellín, Colombia 38
work page internal anchor Pith review Pith/arXiv arXiv
discussion (0)
Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.