BBC: Entropy is a measure of the number of internal arrangements that a system can exhibit. For a closed system, entropy inevitably increases, as defined by the second law of thermodynamics. A related quantity, causal path entropy, measures the number of possible arrangements a system could have on its way to possible future states. By providing a route toward greater complexity, causal path entropy could conceivably serve as a model for how intelligence develops. With that idea in mind, Alex Wissner-Gross of Harvard University and MIT and Cameron Freer of the University of Hawaii at Manoa have proposed the existence of a force that works to maximize causal path entropy. They created simulations of simple physical systems that accounted for that force and found that the effects were profoundâmdash;a particle in a box moved to the center and a pendulum on a sliding pivot moved to an inverted position that would be unstable without the force. They then created physical models that reproduced standard animal intelligence tests. The models behaved in ways analogous to the development of tool use and of social cooperation, both characteristics of basic levels of cognition. However, whereas the models are suggestive of a connection between entropy and intelligence, they are descriptive rather than explanatory and don’t give any evidence of the actual existence of a force that maximizes future possible arrangements of a system.
The finding that the Saturnian moon may host layers of icy slush instead of a global ocean could change how planetary scientists think about other icy moons as well.
Modeling the shapes of tree branches, neurons, and blood vessels is a thorny problem, but researchers have just discovered that much of the math has already been done.
January 29, 2026 12:52 PM
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