A copy of this work was available on the public web and has been preserved in the Wayback Machine. The capture dates from 2017; you can also visit the original URL.
The file type is
We consider polynomial-time Turing machines that have access to two oracles and investigate when the order of oracle queries is significant. The oracles used here are complete languages for the Polynomial Hierarchy (PH). We prove that, for solving decision problems, the order of oracle queries does not matter. This improves upon the previous result of E. Hemaspaandra, L. A. Hemaspaandra, and H. Hempel (1998, J. Universal Computer Sci. 4, 574-588), who showed that the order of the queries doesdoi:10.1006/inco.2000.2918 fatcat:gdwhmor7nnfndly2o5pnkrb62i