【广发英雄帖】请教论坛高人能帮我解释一下 long-range force 和 short-range force。 大家有点想法都可以说啊，互相刺激一些想法。
这个range是基于什么尺度？
常见的力中哪些是 long哪些是short的？
Gravity显然是long，那么范德华力是不是，friction是不是，最重要valence bond呢？
最近在研究cemented clay，就是 cement 与clay 的bonding问题。
In cemented, saturated, fine-grained soils, both frictional bonds and brittle cementation bonds operate simultaneously.
The internal force field in the brittle cementation bonds is essentially due to short-range force, and hence has no role to play either in holding water in the pores or in the deformation response of the soil, which only dependent on the osmotic long range force.
---§ 1998. Nagaraj&Pandian. Compressibility behaviour of cemented soils
The highly polar water molecule has the ability to form strong bonds with the surface of soil particles, as well as with the exchangeable cations that surround it. The strong short range adsorption forces hold one to four molecular layers of water at the surface of the soil particles. This water is said to be adsorbed.
---1996. Terzaghi&Peck. Soil mechanics in engineering practice.
这两个文献中的short range force 是否一样？
