Entropisen

Entropisen is a term found primarily in speculative or fictional contexts to designate a scalar quantity that characterizes the systemic tendency toward disorder or information loss across a network of interacting subsystems. Unlike established technical terms, entropisen has no universally accepted definition in mainstream physics or information theory, and its meaning varies by author or scenario.

In a hypothetical non-equilibrium thermodynamics framework, entropisen can be described as the rate of change of entropy, dS/dt, incorporating both internal entropy production and entropy exchange with the surroundings. When applied to a closed system, entropisen tends to coincide with the conventional entropy production rate, often denoted sigma, which is nonnegative. For open systems, entropisen may be written as sigma = sigma_interior + sigma_boundary, reflecting irreversible processes inside the system and material or energetic exchange with the environment. In this sense entropisen is measured in units of entropy per unit time (joules per kelvin per second, J K−1 s−1).

Some formulations distinguish entropisen as an effective or operational entropy production that captures multi-scale or network-level disorder, including information transfer and structural organization. In information-theoretic analogies, it can be related to changes in Shannon entropy or to the mutual information among subsystems, though such connections are not standardized.

Usage and reception: The term appears in speculative essays, thought experiments, and some science-fiction narratives, but it is not part of formal curricula or peer-reviewed terminology. As such, its definitions, properties, and implications are context-dependent and not universally agreed upon.

See also: Entropy, Entropy production, Non-equilibrium thermodynamics, Shannon information, Information theory.