A ghost is a synth model created from integrating a Biocoherence Neurogenesis captured model of quantum states in the human brain with a classical Copy. Initially developed by Nexus, the technology was licensed and then abandoned by Pharmatica Group and only remains in very limited use, usually via QHackers using grey market 12Quan terminals. The technology was commercially superseded by better Copies, however several notable scientists such as Hannah Weiss-Martin maintain that integrating a model of the quantum fluctuations in the brain is the only way to create true brain copies which are not philosophical zombies.

A ghost uses a phase-preserving snapshot of the subject’s cognitive momentum, integrated with a classic model created via an optogenetic neural lace. Sessions can run only on quantum hardware, and as inference proceeds a process of Progressive Ontological Dissolution (POD) occurs due to the information-disturbance tradeoff, eroding the traits of the emulated personality. This necessitates periodic resets to the pristine base, discarding any session-acquired memories. This is one of the reasons (along with requirement for quantum computers) that the technology was never commercially successful, however there remains a thriving community of QHackers creating and sharing models, and there are many recordings which show ghosts which, although confused by their current situation, do appear to genuinely resemble the original for the short period of time they can be activated for. In recent years QHackers have had some success in lengthening a ghost's POD period, which is known colloquially as its Pull Of Death.