The Markov approximation is arguably the most ubiquitous tool in physics, underpinning quantum master equations, stochastic processes, and -- via Shannon's channel model and Lamport's logical clocks -- the foundational assumptions of distributed computing. It is widely assumed that Markovianity inherently implies temporal asymmetry: that the Markov property is a forward-in-time-only (FITO) construct. We show that this assumption is a category mistake in the sense of Ryle (1949). Guff, Shastry, and Rocco (2025) have recently demonstrated that the Markov approximation applied to the Caldeira-Leggett model -- a paradigmatic open quantum system -- maintains time-reversal symmetry in the derived equations of motion. The resulting time-symmetric formulations of quantum Brownian motion, Lindblad master equations, and Pauli master equations describe thermalisation that can occur in two opposing temporal directions. Asymmetry arises not from the dynamics but from boundary conditions. We trace how Markovianity's assumed directionality propagated from physics through Shannon's information theory to Lamport's happens-before relation and the impossibility theorems of distributed computing (FLP, CAP, Two Generals). Each step encodes FITO as convention, then treats it as physical law -- the same category mistake repeated across domains. The Surrey result establishes that this conflation is not merely philosophically suspect but mathematically unnecessary: the most fundamental approximation used to derive irreversibility is itself time-symmetric.

翻译：马尔可夫近似可以说是物理学中最普遍的工具，它支撑着量子主方程、随机过程，并且——通过香农的通道模型和兰波特的逻辑时钟——也支撑着分布式计算的基本假设。人们普遍认为，马尔可夫性本质上隐含着时间不对称性：即马尔可夫性质是一种仅向前时间（FITO）的构造。我们证明，这一假设是赖尔（1949）意义上的范畴错误。古夫、沙斯特里和罗科（2025）最近证明，应用于卡代拉-莱格特模型——一个典型的开放量子系统——的马尔可夫近似在推导出的运动方程中保持了时间反演对称性。由此产生的量子布朗运动、林德布拉德主方程和泡利主方程的时间对称形式描述的热化过程可以在两个相反的时间方向上发生。不对称性并非源于动力学，而是源于边界条件。我们追溯了马尔可夫性被假定的方向性如何从物理学出发，通过香农的信息论，传播到兰波特的发生在前关系以及分布式计算的不可能性定理（FLP、CAP、两将军问题）。每一步都将FITO编码为约定，然后将其视为物理定律——这是同一范畴错误在不同领域的重复。萨里大学的研究结果证实，这种混淆不仅在哲学上可疑，而且在数学上是不必要的：用于推导不可逆性的最基本近似本身是时间对称的。