It can be as small as you like - down to a quantum level.
M apex :)
The quantity that is most likely to be the smallest in the equation E=mc^2 is the mass (m). Mass is typically much smaller than the speed of light squared (c^2), and energy (E) can be significant due to the speed of light's large value.
Must be m! C is the speed of light and E is a multiple of m.
mass
E (Energy) equals M (Mass) times C2 (speed of light square)
massM = mass
M represents Mass
M stands for Mass
M stands for the mass.
E=m*c2
zero mass = zero energy
it means e = MC2 which is M x c x 2