Feasible Interpolation for QBF Resolution Calculi

@article{Beyersdorff2015FeasibleIF,
  title={Feasible Interpolation for QBF Resolution Calculi},
  author={Olaf Beyersdorff and Leroy Chew and Meena Mahajan and Anil Shukla},
  journal={Log. Methods Comput. Sci.},
  year={2015},
  volume={13}
}
In sharp contrast to classical proof complexity we are currently short of lower bound techniques for QBF proof systems. We establish the feasible interpolation technique for all resolution-based QBF systems, whether modelling CDCL or expansion-based solving. This both provides the first general lower bound method for QBF calculi as well as largely extends the scope of classical feasible interpolation. We apply our technique to obtain new exponential lower bounds to all resolution-based QBF… 

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