Hi, I have a few question which risen from SF movies or computer games, and want to know whether it is possible or not. 1. "Energy" shields: that cover the surface of a ship protecting it from cosmic radiations and collisions with other ships. Is it possible to create a shield of ionized particles, an EM field that protects the ship? Characteristics of this shield: it can regenerate, transparent and it can be severely affected by EMP's. 2. Nanotechnology: nanobots that can construct everything at the atomic level, lets say construct a car where we would provide the nanobots the necessary materials. Will it this be possible? Nanobots used for assembling and disassembling? Another question related to this one, if nanobots could be possible, can it change the configuration of an atom thus creating a new particle?for example transforming Fe intro 2 or more particles of Oxygen ? 3rd question has nothing to do with SF: can we still find anti-matter in "natural environment" eg: not from resulting nuclear reactions.