conductancelike

Conductancelike is a term used to describe a property of a system whose transport response to a driving force resembles electrical conductance. In its typical use, a driving gradient ΔF (electric potential, chemical potential, pressure) induces a flux J that is approximately proportional to ΔF: J ≈ G ΔF, where G is a conductancelike coefficient. More generally, the relation can be written in tensor form J_i = ∑_j G_ij ΔF_j, akin to Ohm's law.

It is used across disciplines: In electronics, a component or network may be described as conductancelike if its current–voltage relation is linear within the operating range. In biophysics and physiology, ion channels and transport proteins often exhibit conductancelike behavior, with an I–V curve that is approximately linear over a range of voltages; gating or rectification can introduce nonlinearities reducing the applicability of a single G. In porous media and membranes, water or solute fluxes can be described by a conductance-like parameter relating flux to pressure or chemical potential difference. In nanofluidics and gas transport, similar linear-response relations are used as first-order approximations.

Limitations: The label does not imply literal electrical conduction; real systems may depart from linearity due to saturation, nonlinear driving forces, temperature dependence, or rate-limiting steps. The coefficient G may depend on state variables such as temperature, concentration, and history (hysteresis).

Related concepts include conductance, Ohm's law, and linear response theory.