挠率引力效应和它的背景

两类挠率源被讨论，它们分别是宏观转动和排列自旋．在狄拉克粒子作为直接探测体，挠率自旋效应的测量受到较大背景的强烈限制，它们是磁自旋和转动自旋．增加挠率源等价于增加背景本身．因此，新发现的有挠引力结论是，任何狄拉克粒子实验没有希望给出挠率的直接证据，这排除了很多有希望的挠率测量建议．最近提出的挠率间接证据被评论．

Torsion Gravity Effect and its Background

Two kinds of sources of torsion are discussed, which are macroscopic rotation and aligned spin respectively. In the case of Dirac spin panical as a direct sensor for torsion,the detection of torsion-spin effect is constrained by the larger backgrounds strongly,which are magnetic-spin and rotation-spin. Increasing the source of the torsion is equivalent to increasing the background itself. So, the new discovered conclusion on torsion gravity is that any Dirac panical experiments have no hope to give the evidence for torsion directly, which rules out many hopeful suggestions on the torsion detection. The promised indirect evidence for torsion, proposed recently, is reviewed.