According to observations, there is not enough visible mass to explain the rotation speed of stars in the galactic self-gravitating field. It has been noted that this involves gravity field orders of magnitude smaller than the one observed in our solar system and responsible for its dynamics. Therefore, it is natural to look for the strength of the gravitational interaction at distances much bigger than the size of our solar system. In 1934, Dirac and Heisenberg computed a (small) correction to the electrostatic potential of a proton due to the Dirac sea of electrons. This screening makes one contribution to the Lambshift measured in 1947. A similar “screening” exists when massive fermions are scattered by a gravity field. Amazingly, this introduces a very big “screening length” of astrophysical order of magnitude because of the smallness of Newton’s constant. The net result is a change of Newton’s gravitational forces at large distances. This does not introduce any new parameter like the mass of unseen particles interacting by gravitation only. Neither it implies a change of the laws of motion of Newton and Galileo.

根据观测，没有足够的可见质量来解释星系自引力场中恒星的自转速度。已经注意到，这涉及的重力场比我们在太阳系中观察到的重力场小几个数量级，并负责其动力学。因此，在比我们太阳系大小大得多的距离上寻找引力相互作用的强度是很自然的。1934 年，狄拉克和海森堡计算了对狄拉克电子海引起的质子静电势的（小）修正。这种屏蔽对 1947 年测量的兰位移做出了贡献。当大量费米子被重力场散射时，存在类似的“屏蔽”。令人惊讶的是，由于牛顿常数很小，这引入了一个非常大的天体物理数量级“屏蔽长度”。最终结果是牛顿引力在远距离发生变化。这不会引入任何新参数，例如仅通过引力相互作用的看不见的粒子的质量。它也不意味着牛顿和伽利略运动定律的改变。