Question

Why are particles of matter always moving and never at rest

Answer 1

In quantum mechanics matter or particle is situated with its wave function which give rise to non-locality .

There is something known as Zero point motion ,according to Heisenberg uncertainty principle ,you cannot be certain with particle momentum and particle position ,so basically it vibrates .Quantum mechanics say there is always uncertainty in two situation ,this is known as quantum complementary .The wave function may also be responsible for this vibration.

String theory predicts that every particle is made up of vibrating strings ,it may be possible that the features of string is seen in particle .