Conservation of matter, mass, rest mass and energy

[kirsten_2009]

Homework Statement

Could someone please let me know if this is correct? I'm unsure about matter always being conserved, does it change whether we're talking about Newtonian physics or special relativity? To me, matter is conserved regardless but maybe there is something I don't know? Thank-you.

Is matter always conserved? Is mass always conserved? Is rest-mass always conserved? Is energy always conserved?

Homework Equations

The Attempt at a Solution

[/B]
Matter is always conserved
Mass (inertia) is always conserved
Rest-mass is not always conserved
Energy is always conserved

 

[phinds]

You need a better problem statement. For example, energy is NOT conserved, on cosmological scales. Are you talking about local scales or cosmological ones?

Check this out:

http://www.preposterousuniverse.com/blog/2010/02/22/energy-is-not-conserved/