Gregory Ewing <greg.ew...@canterbury.ac.nz>: > Mass on its own is not a conserved quantity. The thing that's > conserved is total energy.
Similarly, momentum is conserved. Whether mass is conserved or not depends on the chosen terminology. > As far as I know, there are no negative masses anywhere in any of our > current theories of physics, nor have we observed anything that would > suggest the need for such a thing. What is not known is how antimatter is affected by gravity: <URL: http://news.berkeley.edu/2013/04/30/is-antimatter-anti-gravity/>. Marko -- https://mail.python.org/mailman/listinfo/python-list
