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27 QTM Moves Suffice

Every position of the Rubik's Cube can be solved in at most
27 quarter turns.

This work was supported in part by an allocation of computing time
from the Ohio Supercomputer Center. It was also supported by
computer time from Kent State University's College of Arts and
Sciences. In order to obtain this new result, 25,000 cosets of
the subgroup U,F2,R2,D,B2,L2 were solved to completion, and
34,000,000 cosets were solved to show a bound of 26. No new
positions at a distance of 26 or 25 were found in the solution
of all of these cosets.