Anti-heterotic Computing

  • Viv KendonEmail author
Part of the Emergence, Complexity and Computation book series (ECC, volume 35)


When two or more different computational components are combined to produce computational power greater than the sum of the parts, this has been called heterotic computing (Stepney et al in 8th workshop on quantum physics and logic (QPL 2011), vol 95, pp 263–273, 2012 [46, EPTCS 95 263]). An example is measurement based quantum computing, in which a set of entangled qubits are measured in turn, with the measurement outcomes fed forward by a simple classical computer, to keep track of the parity of the measurement outcomes on each qubit. The parts are no more powerful than a classical computer, while the combination provides universal quantum computation. Most practical physical computers are hybrids of several different types of computational components, but not all are heterotic. In fact, anti-heterotic, in which the whole is less than the sum of the parts, is the most awkward case to deal with. This occurs commonly in experiments on new unconventional computational substrates. The classical controls in such experiments are almost always conventional classical computers with computational power far out-stripping the samples of materials being tested. Care must be exercised to avoid accidentally carrying out all of the computation in the controlling classical computer. In this overview, existing tools to analyse hybrid computational systems are summarised, and directions for future development identified.



VK funded by the UK Engineering and Physical Sciences Research Council Grant EP/L022303/1. VK thanks Susan Stepney for many stimulating and productive hours of discussions on these subjects and diverse other topics. And for the accompanying stilton scones.


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Authors and Affiliations

  1. 1.Department of PhysicsDurham UniversityDurhamUK

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