Brazilian Journal of Physics

, Volume 49, Issue 6, pp 859–863 | Cite as

Significance of Entangling Operators in Quantum Two Penny Flip Game

  • Sundaresh Sankrith
  • Bihag Dave
  • S. BalakrishnanEmail author
General and Applied Physics


For every rule of a single penny flip game, there exists a unitary operation as a winning strategy for a quantum player. Now, in the two penny flip game, an extra option is available, viz. the use of entangling operators. However, it is known that entangling operators are not useful in this case, and a tensor product of unitary operators works just fine. In this work, we look for the significance of the entangling operators, if any, under the situation that the options available to the classical player are expanded. We extend the problem to a more general case and it is shown that there is no entangling operator capable of guaranteeing the victory of the quantum player. Eventually, we reach the classical game situation in a quantum setup of a game.


Quantum games Penny flip game Two-qubit operator Entangling operator Quantum circuits 



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Copyright information

© Sociedade Brasileira de Física 2019

Authors and Affiliations

  • Sundaresh Sankrith
    • 1
  • Bihag Dave
    • 1
  • S. Balakrishnan
    • 1
    Email author
  1. 1.Department of Physics, School of Advanced SciencesVIT UniversityVelloreIndia

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