Quantum Mind? Can't Do Without the Classical ⚡ экспресс
What does it take to have agency — the ability to act purposefully? Three conditions: a model of the world, evaluation of options, and selection of the best action. It turns out that quantum systems on their own cannot fulfill them. The no-cloning theorem prevents copying information for the model and comparing options, and linearity of evolution prevents selective action. Even approximate cloning doesn't help. Conclusion: agency requires classical resources — this explains the emergence of classical agents in a quantum universe and the limitations of quantum computers for modeling behavior.
Intelligent action begins with a plan. Just as an architect needs blueprints to evaluate options, any agent with will needs to repeatedly copy data about reality. But quantum mechanics forbids exact copying of unknown states — the fundamental theorem was discovered by Wojciech Zurek and William Wootters. A purely quantum object cannot preserve a 'snapshot' of its environment, nor compare alternative future scenarios.
You can try to copy approximately, but the quality drops below the level suitable for reliable decisions. Even executing a chosen step is hindered by the linearity of quantum equations: you can't simply single out one outcome from a multitude of superimposed probabilities. An architect in the quantum world is left without a pencil that wouldn't break with every attempt to sketch a blueprint.
The conclusion is striking: reason, will, and goal-directedness require classical 'parts' — they act as a rigid stage with clear boundaries, like spacetime curvature or the speed of light limit, against which the drama of choice unfolds. Most unexpectedly, this no-cloning prohibition is not a bug but a safeguard. It guarantees the inviolability of quantum information, paving the way to absolutely secure communication.
🎯 The no-cloning theorem states: it is impossible to create an exact copy of an arbitrary unknown quantum state. This is not a technical limitation but a fundamental law of nature.
🎬 In science fiction, the idea of quantum consciousness appears frequently (for instance, in Hannu Rajaniemi's novel 'The Quantum Thief'), but new results show that without a classical component, no quantum 'thinking' is possible.