Because assemblers will let us place atoms in almost any reasonable arrangement (as discussed in the Notes), they will let us build almost anything that the laws of nature allow to exist. In particular, they will let us build almost anything we can design - including more assemblers. The consequences of this will be profound, because our crude tools have let us explore only a small part of the range of possibilities that natural law permits. Assemblers will open a world of new technologies.

° Will the uncertainty principle of quantum physics make molecular machines unworkable?

° Will the molecular vibrations of heat make molecular machines unworkable or too unreliable for use?

° Will radiation disrupt molecular machines and render them unusable?