Routes with positive logarithmic utility weights choose rates inversely proportional to their total resource price. Each resource changes its price multiplicatively according to demand minus its increasing supply. For continuous strictly increasing with , the potential is strictly concave and has nonnegative derivative along the dynamics. Positive-price convergence for increasing resource supplies requires positivity on used resources; zero-price faces are invariant.
For finite nonempty routes and positive weights, the potential of increasing-supply resource-price dynamics has a unique maximum. Increasing supplies give a linear penalty at large prices, so its superlevel sets are compact, and logarithmic route terms exclude zero route totals. Used resources have uniformly positive demand on a trapped set; a sufficiently small positive price therefore increases, giving a positive lower bound. The potential derivative is . It has finite integral and is uniformly continuous, so it tends to zero by uniformly continuous integrable functions vanish at infinity. Every limit point then satisfies the unique stationary equations. Unused resource prices decay to zero. Only continuity and strict increase of the supply functions are needed.
In multiplicative resource-price dynamics, a zero price remains zero even if demand exceeds supply there. For one route using two resources, unit weight and supplies , both and are equilibria, while the unique positive equilibrium is . Thus uniqueness on the positive price domain cannot be extended to every nonnegative price trajectory without an extra boundary rule.
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