It has come up else where that the science of 40K is a bit iffy compared to modern science. For example, Monomolecular. In current science monomolecular is a reference to substances that are found in layers one molecule thick. Graphene is an example. But it can also be found in chemistry where two liquid chemical compounds react together to create a third a molecule thick where they meet. I believe Nylon may be created in such a fashion. But in 40K you have bladed weapons sharpened to a monomolecular edge, or Eldar Shuriken a molecule thick. In this case it seems to be used as an old Sci-Fi shorthand for bladed weapons sharpened beyond what modern science can do. Though such weapons are also made out of exotic materials which are both harder and better at maintaining this edge than modern materials. These weapons have to be better than more conventional bladed weapons due to the fact they have to overcome armour the best modern blade would barely scratch. This is a typical Sci-Fi Trope. http://tvtropes.org/pmwiki/pmwiki.php/Main/SharpenedToASingleAtom Can you think of any other 40K Science that can do with addressing? If so feel free to post.