如果所以粒子的電荷相反，世界會是怎樣？

Physics knowledge at present still doesn't know what would happen in a world of ant-atoms.

The first anti-atom, an anti-hydrogen, was produced in 1995 at CERN (European Organization for Nuclear Research). In 2002, a large number of anti-hydrogen atoms at low energies were produce by the Anti-proton Deccelerator at CERN. This is the only ant-matter that physicists have sucessfully produced so far.

Physicists around the wrold are still experimenting to find out if anti-hydrogen behaves at all like hydrogen. Once the behaviour of anti-atoms are known, this might help to understand the world of anti-matter.

The follwoing web-site gives a good introduction to anti-matter, you may wish to have a look on it:

http://discover.positron.edu.au/making-our-own-antimatter/anti-atoms/

nothing changed for human scale. because the force dominate us is still unchanged, coz the multiplication can exchange. like a X b = b X a.