For the first time, researchers have gauged the computational limit of an organism without a nervous system—the slime mold Physarum polycephalum. By analyzing changes in its shape (area, perimeter, fractal dimension) and applying the Margolus–Levitin theorem (which links computation speed to available energy), they showed it can perform up to 10³⁶ logical operations in a day, using hydromechanical, chemical, and even quantum-optical degrees of freedom. Its computational power grows linearly with energy in a non-equilibrium steady state. This approach opens the door to comparing the computational abilities of diverse life forms—from bacteria to neural networks.
Physarum polycephalum is a tiny brainless slime mold, resembling spilled lemonade. But this blob, living in humid environments, can solve mazes. Its secret lies in a unique way of processing information: it uses fluid flows and chemical signals, turning its entire body into a kind of liquid processor. Every movement, every reaction becomes a computational step.
Physicists applied the physical limit of computation speed, linked to energy, to this organism. It turned out that in a day, this "slime" performs up to 10³⁶ operations — many orders of magnitude more than all of humanity's computers combined. An amazing detail: computational power scales with size — as if each new millimeter adds a separate processing unit, right during movement.
This approach allows comparing the "mental" abilities of all carbon-based life — from bacteria to plants — and even to peer into the future of artificial intelligence. Perhaps swaying colonies of microorganisms in the wind, or creatures gliding along the bottom, are also conducting silent computations that we never suspected.
🎯 In a single gram of this slime mold lies computational power comparable to thousands of supercomputers — and all without a single transistor.