International Journal of Theoretical Physics

, Volume 47, Issue 1, pp 200–211 | Cite as

A Macroscopic Device for Quantum Computation

  • Diederik Aerts
  • Ellie D’Hondt
  • Bart D’Hooghe
  • Marek Czachor
  • Jeroen Dehaene
  • Bart De Moor


We show how a compound system of two entangled qubits in a non-product state can be described in a complete way by extracting entanglement into an internal constraint between the two qubits. By making use of a sphere model representation for the spin 1/2, we derive a geometric model for entanglement. We illustrate our approach on 2-qubit algorithms proposed by Deutsch, respectively Arvind. One of the advantages of the 2-qubit case is that it allows for a nice geometrical representation of entanglement, which contributes to a more intuitive grasp of what is going on in a 2-qubit quantum computation.


Quantum computation Entanglement Macroscopic quantum models 


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Copyright information

© Springer Science+Business Media, LLC 2007

Authors and Affiliations

  • Diederik Aerts
    • 1
  • Ellie D’Hondt
    • 1
  • Bart D’Hooghe
    • 1
  • Marek Czachor
    • 2
  • Jeroen Dehaene
    • 3
  • Bart De Moor
    • 3
  1. 1.Leo Apostel Centre for Interdisciplinary Studies (CLEA) and Foundations of the Exact Sciences (FUND), Department of MathematicsVrije Universiteit BrusselBrusselsBelgium
  2. 2.Katedra Fizyki Teoretycznej i Metod MatematycznychPolitechnika GdańskaGdańskPoland
  3. 3.SISTA, Department of Electrical Engineering (ESAT), Faculty of EngineeringKatholieke Universiteit LeuvenLeuvenBelgium

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