[1] viXra:0809.0005 [pdf] submitted on 23 Sep 2008
Authors: Maurizio Michelini
Comments: recovered from sciprint.org
The G measurements are made with torsion balance in �vacuum� to the aim of eliminating
the air convection disturbance. Nevertheless, the accuracy of the measured G values
appears unsatisfying. In 2000 J.Luo and Z.K.Hu first denounced the presence of some
unknown systematic problem in high vacuum G measurement. In this work a new systematic
effect is analysed which arises in calm air from the non-zero balance of the overall
momentum discharged by the air molecules on the test mass in the vacuum chamber. This
effect is normally negligible, but the disturbing force becomes comparable to the
gravitational force when the chamber pressure drops to about 10-5 bar , at which the
molecule mean free path equals the thickness of the meatus facing the test mass. At the
epoch of Heyl�s measurement at 1 millibar (1927), the technology of vacuum pumps
reaching void levels up to 10-9 bar was developed, but this chance was not used. The
recent G measurements used high vacuum techniques up to 10-10 bar and 10-11 bar, so the
effect of the air meatus results very little. What happened to the �missing� measurements
made at vacuum pressures in the �forbidden� interval between millibar and nanobar ? As a
matter of fact, we were not able to find the related papers in the literature. This lack
appears embarrassing in absence of an adequate physical explanation.
Category: Classical Physics