Quantum theorists argue consciousness depends on physical processes classical computation cannot reproduce. Roger Penrose, who shared the 2020 Nobel Prize in Physics, and Stuart Hameroff developed Orchestrated Objective Reduction, which locates a non-computable quantum event inside microtubules in neurons rather than in classical synaptic firing. Harald Atmanspacher’s dual-aspect monism, built on the Pauli-Jung conjecture, treats mind and matter as two aspects of one underlying reality connected through quantum-like correlations rather than ordinary causal signalling. Kelvin McQueen combines integrated information theory with continuous spontaneous localization models of quantum collapse, trying to specify which collapse events would carry integrated information.
If any version of this position is correct, a classical digital computer, however large, cannot become conscious no matter how its software is organised, because the substrate itself is missing physics the theory says is required. For the underlying theories, see quantum theories on the consciousness theories index; for the full researcher directory, see all consciousness researchers.