Armond Duwell

Quantum information does not exist

Abstract Some physicists seem to believe that quantum information theory requires a new concept of information (Jozsa, 1998, Quantum information and its properties. In: Hoi-Kwong Lo, S. Popescu, T. Spiller (Eds.), Introduction to Quantum Computation and Information, World Scientific, Singapore, (pp. 49–75); Deutsch & Hayden, 1999, Information flow in entangled quantum subsystems, preprint quant-ph/9906007). I will argue that no new concept is necessary. Shannons concept of information is sufficient for quantum information theory. Properties that are cited to contrast quantum information and classical information (i.e., Shannon information) actually point to differences in our ability to manipulate, access, and transfer information depending on whether quantum systems, opposed to classical systems, are used in a communication system. I also demonstrate that conceptually puzzling phenomena in quantum information theory, such as dense coding, teleportation, and Schumacher coding, all of which are cited as evidence that a new concept of information is required, do not have to be regarded as such.

The Many‐Worlds Interpretation and Quantum Computation

David Deutsch and others have suggested that the Many‐Worlds Interpretation of quantum mechanics is the only interpretation capable of explaining the special efficiency quantum computers seem to enjoy over classical ones. I argue that this view is not tenable. Using a toy algorithm I show that the Many‐Worlds Interpretation must crucially use the ontological status of the universal state vector to explain quantum computational efficiency, as opposed to the particular ontology of the MWI, that is, the computational histories of worlds. As such, any other interpretation that treats the state vector as representing real ontological features of a system can explain quantum speedup too.

Exploring the Frontiers of Computation: Measurement Based Quantum Computers and the Mechanistic View of Computation

In this paper I investigate measurement based quantum computers (MBQCs) using the mechanistic view of computation. I begin by demonstrating that Turing’s work cannot serve as an analysis of computation. I proceed to describe the mechanistic view of computation and then apply it to MBQCs. That computers as peculiar as MBQCs can be handled by the mechanistic view provides good confirmation for it. Additionally, I will show how the mechanistic view helps us understand how MBQCs work, and how this understanding might be applied to expand the frontiers of computation.

Bananaworld: Quantum Mechanics for Primates

respond... ’, 109, 270, etc.). Therefore, Cunning’s text is not a mere account of Cavendish’s philosophy: it is more aptly defined as a dialogue with Cavendish, in which her views are presented, criticised, defended, and finally placed in a larger philosophical context. Cunning successfully demonstrates that Margaret Cavendish fully deserves to be included in the Routledge series, ‘Arguments of the Philosophers’.